explain xkcd - User contributions [en]

Talk:144: Parody Week: A Softer World

2026-04-09T11:49:23Z

Giraffequeries:

XKCD Volume 0 also has

UATAQANUUNG QSICHINGNKUCHAANG CHSICHINGSICHINGNG

SICHINGULUUNGUUNG CHASNGATAQANCHATAQANNG

above the strip. {{unsigned ip|172.69.214.108|23:04, 11 January 2024 (UTC)}}

Actually, this one's kinda cute. [[Special:Contributions/172.68.2.84|172.68.2.84]] 18:32, 21 March 2024 (UTC)

What's up with the Android Series thing? It's mentioned in the desc as a series concerning having sex with robots but the page for it doesn't exist and I've never heard of it before.

Blue Eyes

2026-02-07T20:39:09Z

Giraffequeries: Took this page out of My Hobby. if someone can explain what the circumstances were for putting this in said category in the first place please contact me

{{comic
| date =
| title = Blue Eyes
| lappend = blue_eyes.html
| extra = yes
| before = <center><table width="90%"><tr><td><center><big>If you like formal logic, graph theory, sappy romance, bitter sarcasm, puns, or landscape art, check out my webcomic, [https://www.xkcd.com/ xkcd]</big>.

[[File:frame.jpg|link=https://www.xkcd.com/]]

Blue Eyes:

The Hardest Logic Puzzle in the World</center>

<big>A group of people with assorted eye colors live on an island. They are all perfect logicians -- if a conclusion can be logically deduced, they will do it instantly. No one knows the color of their eyes. Every night at midnight, a ferry stops at the island. Any islanders who have figured out the color of their own eyes then leave the island, and the rest stay. Everyone can see everyone else at all times and keeps a count of the number of people they see with each eye color (excluding themselves), but they cannot otherwise communicate. Everyone on the island knows all the rules in this paragraph.

On this island there are 100 blue-eyed people, 100 brown-eyed people, and the Guru (she happens to have green eyes). So any given blue-eyed person can see 100 people with brown eyes and 99 people with blue eyes (and one with green), but that does not tell him his own eye color; as far as he knows the totals could be 101 brown and 99 blue. Or 100 brown, 99 blue, and he could have red eyes.

The Guru is allowed to speak once (let's say at noon), on one day in all their endless years on the island. Standing before the islanders, she says the following:

'''"I can see someone who has blue eyes."'''

Who leaves the island, and on what night?

There are no mirrors or reflecting surfaces, nothing dumb. It is not a trick question, and the answer is logical. It doesn't depend on tricky wording or anyone lying or guessing, and it doesn't involve people doing something silly like creating a sign language or doing genetics. The Guru is not making eye contact with anyone in particular; she's simply saying "I count at least one blue-eyed person on this island who isn't me."

And lastly, the answer is not "no one leaves."

I've done my best to make the wording as precise and unambiguious as possible (after working through the explanation with many people), but if you're confused about anything, please let me know. A word of warning: The answer is not simple. This is an exercise in serious logic, not a lateral thinking riddle. There is not a quick-and-easy answer, and really understanding it takes some effort.</big>

<center>[[File:hyphen.jpg|link=https://www.xkcd.com/]]</center>

<center><big>I didn't come up with the idea of this puzzle, but I've written and rewritten it over the the years to try to make a definitive version. The guy who told it to me originally was some dude on the street in Boston named Joel.</big></center>
</td></tr></table></center>
}}
{{TOC}}
==Explanation==
{{incomplete|
*The date is incorrect, the comic was available long before October 11, 2006. The earliest date we have is [https://web.archive.org/web/20041024201125/http://68.57.186.221:8080/ October 24th, 2004] (see fourth link on the page), and the earliest version of the comic is from [https://web.archive.org/web/20041109034300/http://68.57.186.221:8080/blue_eyes.html November 4th, 2004].

*Additionally, both the puzzle [https://xkcd.com/solution.html and the solution] (here's an [https://web.archive.org/web/20061102070433/https://xkcd.com/solution.html earlier version of the solution])were modified and updated several times since its release. Update the explanation and the [[#Trivia]] with this info.}}
{{misc page}}

[[xkcd]]'s [http://xkcd.com/blue_eyes.html Blue Eyes] puzzle is a logic puzzle posted around the same time as comic [[169: Words that End in GRY]]. [[Randall]] calls it "The Hardest Logic Puzzle in the World" on its page, but whether it really is the hardest is up to speculation.

The page contains two comics. On the top is [[82: Frame]], and at the bottom is [[37: Hyphen]]. These particular comics may have been chosen intentionally, as 82 involves a mind screw (and formal logic can be pretty mind-screwy to the uninitiated) and 37 involves linguistic ambiguity, which Randall has explicitly gone out of his way to avoid (interestingly, [[169]] involves the infuriating ambiguity caused by misquoting riddles). That said, Randall could have simply picked those comics out of a hat to plug for his comic (which he also does explicitly), and the date of release could also be completely random.

Randall cites "some dude on the streets in Boston named Joel" as his source for the comic idea, although he's rewritten it.

==Puzzle==
A group of people with assorted eye colors live on an island. They are all perfect logicians -- if a conclusion can be logically deduced, they will do it instantly. No one knows the color of their eyes. Every night at midnight, a ferry stops at the island. Any islanders who have figured out the color of their own eyes then leave the island, and the rest stay. Everyone can always see everyone else and keeps a count of the number of people they see with each eye color (excluding themselves), but they cannot otherwise communicate. Everyone on the island knows all the rules in this paragraph.

On this island there are 100 blue-eyed people, 100 brown-eyed people, and the Guru (she happens to have green eyes). So, any given blue-eyed person can see 100 people with brown eyes and 99 people with blue eyes (and one with green), but that does not tell him his own eye color; as far as he knows the totals could be 101 brown and 99 blue. Or 100 brown, 99 blue, and he could have red eyes.

The Guru is allowed to speak once (let's say at noon), on one day in all their endless years on the island. Standing before the islanders, she says the following:

"I can see someone who has blue eyes."

Who leaves the island, and on what night?

==Solution==
Randall's solution can be found at [http://xkcd.com/solution.html xkcd.com/solution.html]. Here are some observations that help simplify the problem:

No one without blue eyes will ever leave the island, because they are given no information that can allow them to determine which non-blue eye color they have. The presence of the non-blue-eyed people is not relevant at all. We can ignore them. All that matters is when the blue-eyed people learn that they actually are blue-eyed.

There are two ways in which blue-eyed people might leave the island. A lone blue-eyed person might leave on the first night because they can see that no one else has blue eyes, so the Guru must have been talking about them. Or an accompanied blue-eyed person can leave on a later night, after noticing that other blue-eyed people have behaved in a way that indicates they have noticed that their eyes are also blue.

The problem is symmetrical for all blue-eyed people, so this means they will either all leave at once or all stay forever.

===Theorem===
If there are N blue-eyed people, they will all leave on the Nth night.

===Dual logic===
Blue-eyed people leave on the 100th night.

If you (the person) have blue eyes then you can see 99 blue-eyed and 100 brown eyed people (and one green eyed, the Guru).
If 99 blue-eyed people don't leave on the 99th night, then you know you have blue eyes and you will leave on the 100th night knowing so.

===Intuitive proof===
Imagine a simpler version of the puzzle in which, on day #1, the Guru announces that she can see at least 1 blue-eyed person, on day #2, she announces that she can see at least 2 blue-eyed people, and so on until the blue-eyed people leave.

So long as the Guru's count of blue-eyed people doesn't exceed your own, then her announcement won't prompt you to leave. But as soon as the Guru announces having seen more blue-eyed people than you've seen yourself, then you'll know your eyes must be blue too, so you'll leave that night, as will all the other blue-eyed people. Hence our theorem obviously holds in this simpler puzzle.

But this "simpler" puzzle is actually perfectly equivalent to the original puzzle. If there were just one blue-eyed person, they would leave on the first night, so if nobody leaves on the first night, then everybody will know there are at least two blue-eyed people, so there's no need for the Guru to announce this on the second day. Similarly, if there were just two blue-eyed people, they'd then recognize this and leave on the second night, so if nobody leaves on the second night, then there must be a third blue-eyed person inspiring them to stay, so there's no need for the Guru to announce this on the third day. And so on... The Guru's announcements on the later days just tell people things they already could have figured out on their own.

It's obvious that our theorem holds for the "simpler" puzzle, and this "simpler" puzzle is perfectly equivalent to the original puzzle, so our theorem must hold for the original puzzle too.

Another way of looking at it is to use selective attention. Although each blue-eyed person can see each other blue-eyed person on the island, they don't need to. The only thing they need to know in order to determine whether to leave on night N is whether they can see an Nth person with blue eyes. On night 1, they only need to see 1 other blue-eyed person to not leave; on night 2, they can see 2 other blue-eyed people, so they don't leave; and so on until night 100, when they can't see a 100th blue-eyed person, and then leave.

===Formal proof===
To prove this more formally, we can use mathematical induction. To do that, we'll need to show that our theorem holds for the base case of N=1, and we'll need to show that, for any given X, *if* we assume that the theorem holds for any value of N less than X, then it will also hold for N=X. If we can show both these things, then we'll know the theorem is true for N=1 (the base case), for N=2 (using the inductive step once), for N=3 (using the inductive step a second time) and so on, for whatever value of N you want.

Base case: N=1. If there is just one blue-eyed person, they will see that no one else has blue eyes, know that the Guru was talking about them, and leave on the first night.

Inductive step: Here we assume that the theorem holds for any value of N less than some arbitrary X (integer greater than 1), and we need to show that it would then hold for N=X too. If there are X blue-eyed people, then each will reason as follows: "I can see that X-1 other people have blue eyes, so either just those X-1 people have blue eyes, or X people do (them plus me). If there are just X-1 people with blue eyes, then by our assumption, they'll all leave on night number X-1. If they don't all leave on night number X-1, then that means that there is an Xth blue-eyed person in addition to the X-1 that I can see, namely me. So, if they all stay past night number X-1, then I'll know I have blue eyes, so I'll leave on night number X. Of course, they'll also be in exactly the same circumstance as me, so they'll leave on night number X too."

This suffices to prove our theorem. The base case tells us the theorem holds for N=1. That together with the inductive step tells us that it therefore holds for N=2, and that together with the inductive step again tells us that it holds for N=3, and so on... In particular, it holds for the case the original puzzle asked about, N=100, so we get the conclusion that the 100 blue-eyed people will leave on the 100th night.

==Randall's follow-up questions==
After giving his solution, Randall posed three questions for further thought about the puzzle. They are answered below, in a different order than his.

===Question 2===
:''Each person knows, from the beginning, that there are no less than 99 blue-eyed people on the island. How, then, is considering the 1 and 2-person cases relevant, if they can all rule them out immediately as possibilities?''

Blue-eyed people can't see their own faces, so blue-eyed people can see one less blue-eyed face than non-blue-eyed people can. Even though I can see that there are at least 99 blue-eyed people, I don't know that they can see that, so I need to imagine people who see only 98, who would base their actions in part by imagining people who can see only 97 who would base their actions in part by imagining people who can see only 96, and so on... All the levels are relevant. (It's like [https://www.youtube.com/watch?v=U_eZmEiyTo0 the Princess Bride scene] where Vizzini is trying to think about what Wesley would choose in part based upon Wesley thinking about what Vizzini would choose in part based upon... "So clearly I cannot choose the one in front of me!") Each layer of thinking about what someone else might be thinking about can decrement by 1 the number of blue-eyed people visible to the lattermost imagined person, so it turns out that even the base case with N=1 blue-eyed person is relevant. As the days go by, some of the more far-fetched "he might be thinking that I might be thinking that he might be thinking that I might be thinking that..." hypotheses get ruled out. But it's only after night N-1 that the blue-eyed people rule out all the possibilities in which they have brown eyes, whereas the brown-eyed people only learn on night number N that they don't have blue eyes.

It might help to think of all the different situations people might be in. (Remember brown-eyed people always are situated where they can see one more blue-eyed face than blue-eyed people can.)

'''Situation 0.''' If I see 0 blue-eyed people, I can leave right after the announcement on night 1.
'''Situation 1.''' If I see 1 blue-eyed person, then they might be in situation 0 and about to leave on night 1; or else they might be in situation 1 just like me, in which case we'll both leave together on night 2.
'''Situation 2.''' If I see 2 blue-eyed people, they might each be in situation 1 watching to see whether anyone in situation 0 leaves the first night (I know nobody will leave that night, but they wouldn't know this), in which case they would leave together on night 2; or else they might be in situation 2 just like me, in which case we'll all leave together on night 3.

⋮
'''Situation N.''' If I see N blue-eyed people, they might be in situation N-1 watching to see whether any people in situation N-2 leave on night N-1 (I know nobody will leave that night, but they wouldn't know this), in which case they would leave together on night N; or else they might be in situation N just like me, in which case we'll all leave together on night N+1.
⋮

Even though I start out in situation 99, I need to worry that the blue-eyed people might be in situation 98, so I need to wait long enough for people in situation 98 to figure out what's going on, and then see whether they act like they are indeed in situation 98. But if they're in situation 98, then they're worrying about whether all the blue-eyed people might be in situation 97, so they're going to need to wait long enough for people in situation 97 to figure out what's going on. Of course, that requires waiting long enough for people in situation 96 to figure out what's going on, and so on, down all the way to situation 0. All the levels are relevant, and it takes a separate day to eliminate each level, which is why the entire process takes N days.

===Question 3===
:''Why do they have to wait 99 nights if, on the first 98 or so of these nights, they're simply verifying something that they already know?''

Consider an analogy. I've heard that miners used to take canaries down into mines because canaries pass out more quickly in poor air than miners do. Suppose you know the canary will do fine for 98 or so seconds, and then pass out if the air is bad. As you watch the canary for those 98 seconds, there's a sense in which you're just verifying something you already know (it'll do fine), but it seems more accurate to say that your best detector for the quality of the air takes 98 seconds to give you a reading, and you're waiting 98 seconds to see what that reading is.

When the blue-eyed people wait 98 or so days to leave, that's because their best available detector of their own eye-color takes 98 or so days to give a reading. (This detector involves watching what the other blue-eyed people do, and of course they themselves are waiting on a detector that takes 97 or so days to yield its result...) There's a sense in which they're "simply verifying something that they already know", but it seems more accurate to say that they're waiting for their best available detector of their own eye-color to deliver its reading.

===Question 1===
:''What is the quantified piece of information that the Guru provides that each person did not already have?''

Before the Guru speaks, the hypothetical chain of A imagining B imaging C imagining D... imagining Z seeing N blue-eyed people cannot terminate uniquely. Z seeing no blue-eyed people can consider whether they are blue-eyed. This means it is not {{w|Common knowledge (logic)|common knowledge}} that there are blue eyes. Once the Guru makes their pronouncement it is common knowledge, and every chain of reasoning must terminate at 1 blue-eyed person and Z above would have to conclude that they had blue eyes. From then on, every midnight the common knowledge that there are N blue-eyed people increments by 1 as everyone sees nobody leaving on the ferry.

Stated another way, there's only one stable set of beliefs for the blue-eyed people that would allow them to have so many exist on the island indefinitely. That is if each blue-eyed person believed not only that they have brown eyes, but also that every other blue-eyed person believed, incorrectly, that they had brown eyes. Logic reduces this to "all unknowing blue-eyes believes that all known blues-eyes believe that they have brown eyes". The Guru eliminates that particular possibility.

Another straightforward way to understand why the Guru's information is important is thus. Each blue-eyed person knows two sets of information: what the actual situation is on the island (both now and in the past), and what would happen in a hypothetical situation. Each blue-eyed person then needs only to compare the actual situation to a known hypothetical one, and if it matches up, then they take the corresponding action. Consider this: If there were only one blue-eyed person, and the Guru never made the announcement, they would not leave on day 1 because they would not know that N is greater than or equal to 1. Now let's add a second blue-eyed person. Blue-eyes 2 would not be able to inductively determine whether or not to leave on night 2, because blue-eyes 2's knowledge of whether or not to leave on night 2 is dependent on what blue-eyes 1 does on night 1 if and only if blue-eyes 1 knows what to do on night 1. If blue-eyes 1 doesn't know that N is greater than or equal to 1, then blue-eyes 1 doesn't know what to do on night 1. Thus, their lack of leaving gives blue-eyes 2 no new information, since it was an uninformed action and blue-eyes 2's inductive reasoning was dependent on blue-eyes 1 knowing what to do, and so the inductive process never takes off for the hypothetical situation. This means a hypothetical situation for N people cannot be induced. As such, blue-eyes 100 does not have certain knowledge of the hypothetical situation that would occur on nights 99 and 100, and so even though they know N = either 99 or 100, they can't take action on either of those nights, because they have no certain hypothetical situation to compare reality to, and as such cannot have certainty about the actions they should take.

==Transcript==
:[The 'comic page' is mostly text, with two actual images, neither of which relate to the text.]
:[The first image is that of the comic [[82: Frame]]. It is positioned above the title.]
:[The second image is that of the comic [[37: Hyphen]]. It is positioned directly above the last sentence.]

==Trivia==
The web page which contains the puzzle has no {{w|CSS|style sheet}}. The font size of the heading and subheading is increased with deprecated HTML tags, rather than with heading tags. The way the page is displayed therefore depends on the browser's settings. Despite this fact, due to a similarity of default settings between computers, most computers will display the page with a white background, black text, and the {{w|Times New Roman}} font. However, it has two line breaks after every paragraph instead of HTML paragraph breaks, meaning that paragraph spacing will not vary between browsers, relative to the font size.

{{comic discussion}}

[[Category:Multiple Cueballs]]
[[Category:No title text]]
[[Category:No date]]
[[Category:Comics with lowercase text]]

Talk:833: Convincing

2026-01-23T19:32:15Z

Giraffequeries: ...

My IP address got logged when I was editing this page, since I got accidentally loged out in the proccess. May someone fix this? I feel nervous. [[User:Greyson|Greyson]] ([[User talk:Greyson|talk]]) 18:04, 12 December 2012 (UTC)
::Preumably you wanted to sign your work and think you were prevented by the record.

Just hit the back button and finish what you started then sign out. I leave two paragraph spaces before I sign out to put the awkward sig on its own line. [[User:Weatherlawyer| I used Google News BEFORE it was clickbait]] ([[User talk:Weatherlawyer|talk]]) 21:03, 24 January 2015 (UTC)
:There is no way, short of going to a MySQL prompt and manually editing values, to change the logs that MediaWiki records. However, your IP address is not private information, nor does it personally identify you. It is merely a number in a block of IPs that your ISP pays money to use. An IP address is a temporarily assigned name that your computer uses to communicate with the Internet. Even if you were using a secure connection to a website, your IP address is still transmitted in the clear, otherwise the server could not reply to you. I know there's a lot of scare campaigns that make it sound like you need to protect your IP address like your Social Security Number (or other similar "unique" identifier your government uses to make sure you pay your taxes). If you really are scared that your IP is now "out in public" (which it always has been) unplug your modem long enough for the capacitors to drain (milliseconds probably) then plug it back in. It'll send out a DHCP request to your ISP and they'll give you a new number from their pool. But keep in mind, if you were really scared about someone finding your IP address you'd be using {{w|The Onion Router|Tor}} in the first place and you'd simply change your exit node.

:Links for your edification:
:*https://www.eff.org/deeplinks/2011/08/why-ip-addresses-alone-dont-identify-criminals
:*https://www.eff.org/pages/tor-and-https

:--[[User:Lcarsos|lcarsos]]_a ([[User talk:Lcarsos|talk]]) 18:26, 12 December 2012 (UTC)

:However, now that you have voluntarily associated your user name with the IP address in the edit history... - [[User:Frankie|Frankie]] ([[User talk:Frankie|talk]]) 16:25, 4 January 2013 (UTC)

:That is an i n c r e d i b l y annoying thing to do, and someone has already asked you to stop doing this on your user page, so at least acknowledge him (and preferably edit your comments to fix the issue). [[User:Beanie|Beanie]] ([[User talk:Beanie|talk]]) 14:16, 26 April 2021 (UTC)

I'm pretty sure that the x axis is "Local Armadillo Population Density." Any ideas what the y axis is?[[Special:Contributions/173.245.48.97|173.245.48.97]] 09:31, 18 May 2015 (UTC)

Maybe [[701: Science Valentine]] would be worth mentioning, where Cueball draws a relationship themed graph (ironically without properly labeled axes / any axes at all) [[User:Ruffy314|Ruffy314]] ([[User talk:Ruffy314|talk]]) 02:26, 3 November 2015 (UTC)

I physically cringed looking at that graph. I dislike the amount of nerd points I have accumulated to be affected by this.

307: Excessive Quotation

2026-01-21T15:24:49Z

Giraffequeries: provided an alt explanation for megan's quoting. idk if this makes sense to star wars fans yall can delete that part if ya want

{{comic
| number =307
| date =August 24, 2007
| title =Excessive Quotation
| image =excessive_quotation.png
| titletext =Unfortunately for her, real Star Wars fans are attracted to a gal with a good force choke.
}}

==Explanation==
[[Megan]] just wants to have a normal conversation about the moon, but [[Cueball]] replies with a quote from ''{{w|Star Wars: Episode IV – A New Hope}}'', wherein {{w| Obi-Wan Kenobi}} says: "That's no moon, that's a space station." Megan cuts him off in the manner of another ''Star Wars'' character, the villain {{w|Darth Vader}}, and showing a glimmer of the character's abilities, proceeds to choke him with {{w|The Force}} while modifying another phrase from the same film. (The original quotation was, "I find your lack of faith disturbing.")

There is humor in Megan's hypocrisy, however. Although she is disturbed by Cueball's unoriginal dialogue, she is fine with doing it herself. (It is possible, however, that she finds modifying a quote, rather than just repeating it verbatim, to be original enough. She also may be unaware that she is actually quoting Star Wars, as Megan may just be saying something articulate and accidentally saying something similar to the original quote-however, since it is implied that she has seen A New Hope, this is unlikely.)

''Star Wars'' fans are a weird bunch, however, and the title text states that if a ''Star Wars'' fan met a girl who could do this in real life, it'd only serve to turn him on even more.

==Transcript==
:[Outside, under a crescent moon. Megan holds Cueball up in the air by his neck à la Darth Vader using the force.]
:Megan: It's strange to stare at the moon and think about people walking on it.
:Cueball: That's no moon, it's a—''*gack*''
:Megan: I find your lack of original conversation disturbing.
{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Star Wars]]

3175: Website Task Flowchart

2025-12-26T17:02:01Z

Giraffequeries: the transcript is done

{{comic
| number = 3175
| date = December 1, 2025
| title = Website Task Flowchart
| image = website_task_flowchart_2x.png
| imagesize = 333x683px
| noexpand = true
| titletext = Tired of waiting on hold? Use our website to chat with one of our live agents, who are available to produce words at you 24/7!
}}

==Explanation==
{{incomplete|This page was created by a live agent producing words at you. Don't remove this notice too soon.}}
This is a flowchart comic. It ostensibly shows how to accomplish a task on a generic website. With the improvements to web infrastructure, {{w|accessibility}}, and {{w|user experience}} research over the decades, one might think that this would be simple. And sometimes, indeed, everything just works as expected. However, the flowchart indicates that this system often fails to handle error states gracefully and can {{wiktionary|a chain is only as strong as its weakest link|completely shut down}} when the smallest [[2347: Dependency|dependency]] breaks.

The first step is to try to access the website. This includes {{w|Loading (computing)|pulling it up}}, and possibly {{w|Login|signing into an account}}. Websites may have legitimate or [[792: Password Reuse|nefarious]] reasons to profile their users. Either way, it is often another step in the way of the user's goals.

The very start of the process can already fail if the website doesn't load, you enter an incorrect username or password, or the website's {{w|authentication}} service is having problems and rejecting legitimate credentials, for example. Issues at this stage are often out of the user's control, and can kneecap your productivity if you rely on that website, as was recently discussed in [[3170: Service Outage]]. The flowchart provides no specific {{w|troubleshooting}} guidance, as the exact steps will vary greatly depending on the specific problem, and readers may have their own troubleshooting process similar to [[627: Tech Support Cheat Sheet]]. It could involve visiting another website like "[https://www.isitdownrightnow.com Is It Down Right Now?]" to see if others are having the same issue, double-checking your login information, or looking up any specific error messages the site gives. You may simply have to wait until the broken service is restored.

If you can enter the website, the next part of the flowchart asks if you finished your task successfully. If you have managed to both log in and do your work (perhaps eventually), it simply congratulates you for finishing your task. Failure here could be because of other issues with the website, such as {{w|Software bug|bugs}}, or [[3170: Service Outage|service outages]] in the middle of your work, or simply because the site doesn't have the tools to accomplish your specific task. You may have to use tools that ''are'' available in alternative or creative ways to accomplish what you need to. This might not be an option if your data or workflow relies on a specific site, or if alternatives are sketchy or paywalled.

As the flowchart suggests, troubleshooting a website can be a major deviation from your goals, and can involve following many false leads for hours on end. There's a chance that the issue resolves, putting you back on track. But in the meantime, you're trying to find a solution on your own. According to the chart, talking to tech support is a last resort.

If your troubleshooting fails at either stage, the chart guides you to call the website's {{w|customer service}} line, which is framed as admitting defeat. The flowchart reckons that an {{w|Automated attendant|automated}} phone system will put you {{w|Hold (telephone)|on hold}} and a {{w|On hold messaging|prerecorded message}} will then suggest trying to use the website ''instead'' of calling directly. While this would be helpful for someone calling the support line ''before'' trying the website, it assumes that the site is working properly and that the task can actually be accomplished there. It's like kicking you when you're already down to hear that "advice" after spending hours trying to use a website that simply would not work like you need it to.

From there, the flowchart predicts that you will be so frustrated, you'll throw away both your computer and your phone into the sea before even listening to the rest of the on-hold message. This would be a drastic and non-trivial way of responding to the situation, as it would destroy those devices. (It would, at least, formally end your attempt to use the website.) The flowchart presents this as an inevitability as a form of {{w|hyperbole}}.

The title text is another part of the presumed hold message, perhaps for anyone who had not followed the flowchart as faithfully. It encourages the caller to visit the website's {{w|live chat}} function, a fairly recent development that combines the best and worst aspects of both online and phone-line support. It can be ambiguous whether the "live agent" is zero, one, or many people. You may reach a qualified staff member with all the answers to your questions; or, the conversation may be passed around between various less-than-knowledgeable staff who are merely following a ''script'' with a flowchart process (hopefully more useful than this one) to let them give more expert advice than they might be capable of; or, increasingly, you may connect to a {{w|chatbot}} that processes your queries, follows a similar script, and may be more difficult to reason with or escalate the issue. It may {{wiktionary|triage}} your initial responses before 'bothering' a real human who can help you with your request, if it is able to transfer you to a human at all.

The claim that the agent can "produce words at you" (rather than "talk", "speak", or "communicate") implies that their responses won't convey any information, or perhaps even basic understanding of the problem. If the live chat is open 24/7, you may reach a human agent elsewhere in the world who {{w|English as a second or foreign language|doesn't speak English natively}} and struggles to understand you. This could also be a blatantly honest admission that you will converse with a potentially inexhaustible {{w|large language model}} AI, where the words you receive might demonstrate {{w|Markov chain|even less understanding}} of your problem, as merely being able to send even [[1068: Swiftkey|vaguely logical sequences of words]] might be worse than useless. Additionally, giving random vague sequences of words would add to the user's frustration, strengthening their urge to throw their laptop into the ocean.

==Transcript==
[Caption above the panel:]
Doing a task using a company or organization's website:

[Below this is a flowchart, starting with "Go to website, try to log in"]

[Box 1 (start):] Go to website, try to log in (go to to box 2)

[Box 2:] Did it work? (Yes/No)
*Yes: Go to box 3
*No: Go to box 6

[Box 3:] Try to do your task (go to box 4)

[Box 4:] Did it work? (Yes/No)
*Yes: Go to box 5
*No: Go to box 8

[Box 5 (end):] Nice! Done!

[Box 6:] Spend hours troubleshooting account/login (go to box 7)

[Box 7:] Did it work? (Yes/No)
*Yes: Go to box 3
*No: Go to box 10

[Box 8:] Spend hours troubleshooting website (go to box 9)

[Box 9:] Did it work? (Yes/No)
*Yes: Go to box 5
*No: Go to box 10

[Box 10:] Give up and call customer service (go to box 11)

[Box 11:] Hold message: "Did you know you could do all of this more quickly and easily on our website? Just go to W-W-W dot..." (go to box 12)

[Box 12 (end):] Throw phone and laptop into the sea
{{comic discussion}}

[[Category:Flowcharts]]
[[Category:Internet]]

3032: Skew-T Log-P

2025-10-28T15:13:21Z

Giraffequeries: removed <incomplete transcript>, please check and re-add if transcript is insufficent

{{comic
| number = 3032
| date = January 1, 2025
| title = Skew-T Log-P
| image = skew_t_log_p_2x.png
| imagesize = 569x626px
| noexpand = true
| titletext = The most important quantity for meteorologists is of course the product of latent pressure and temperostrophic enthalpy, though 'how nice the weather is' is a close second.
}}

==Explanation==
{{w|Skew-T log-P diagram}}s are commonly used to plot {{w|atmospheric sounding|atmospheric soundings}} collected by {{w|weather balloon|weather balloons}} or {{w|Constant altitude plan position indicator|other}} [https://rmets.onlinelibrary.wiley.com/doi/abs/10.1002/wea.658 methods]. The name comes from the temperature (T) lines being skewed at a 45-degree angle and the pressure (P) lines being logarithmic in scale. Although it ''looks'' very much like a cross-sectional diagram, it shows non-positional information derived from passing (generally) vertically up through the atmosphere from the initial reference location.

Because the diagrams have a lot of lines on them (isobars, isotherms, adiabats, and mixing ratios, and that's before plotting the actual measurements of temperature and dew point temperature), they can be hard to comprehend. The comic pretends to offer an explanation of one such diagram, but most of the explanations are blatantly incorrect or humorous in nature. The diagram appears to have either measurements from two separate weather measurements or the measured temperature and dewpoint from a single balloon, with solid lines for the primary balloon's two streams of data (often disambiguated by the chosen hue of the line) and dashed ones for the secondary set of data (popped balloon(s) falling back down, a separate second survey balloon rising or estimates derived from weather-radar data). See details in the [[#Table with terms|table]] below. Many weather balloons are designed to rupture after reaching a certain height high in the atmosphere.

[[File:Annotated_Skew_T_diagram.png|thumb|An actual Skew-T Log-P diagram, with several real annotations. The X-axis has temperature (blue diagonal lines in diagram) and the Y-axis has pressure in millibars.]]The true design of a Skew-T Log-P diagram is intended to best represent the nature of the weather in any given column of atmosphere. The pressure (vertical axis, with pressure being inversely related to altitude, more or less) is shown as a logarithmic scale (i.e., Log-P) because it makes altitudes nearly evenly spaced. Plotting pressure proportionately (which must also be from top to bottom, to match its general relationship with altitude) would space features out in ways that would be hard to use and interpret, whereas the logarithmic scale is far more pragmatic. The temperature scale is deliberately tilted, rather than orthogonal, which (together with the logarithmic nature of the inverted pressure scale) allows the typical way that temperatures fall with altitude(≈as pressure falls) to trend roughly vertically, give or take the notable changes that are key to understanding the forecast. Other measurement lines, differently skewed and often also curving across the temperature/pressure skewed-log 'grid', represent various other idealistic relationships (where both T and P vary, keeping another measure constant) that are useful references to meteorologists.

Upon this style of graph are plotted the ''actual'' measurements obtained by releasing a weather balloon or through some other sensor. As well as the variation of actual temperatures and pressures, other retrieved and calculated data is plotted, such as the {{w|dew point}}. The dew point, a function of the air's {{w|absolute humidity|water content}}, temperature, and pressure, is where condensation begins. By observing how the actual measurements and dew point line converge and cross, the development and nature of clouds can be tracked and pinned to specific cloud layers. Further details may also be included, such as wind-direction and wind-speed indications (often to the side of the plot) to give a visual cue about possible {{w|wind shear}} and/or to suggest which direction of adjacent weather-station readings may hold clues as to what changes may later blow in above the current site.

In the title text it is stated that "The most important quantity for meteorologists is of course the product of latent pressure and temperostrophic enthalpy, though 'how nice the weather is' is a close second". So it jokes by comparing a non-existent, complicated-sounding product (temperostrophic enthalpy is not actually a thing) with a simple sentence about how nice the weather is.

==Table with terms==
{| class="wikitable"
!Item in comic
!Correct?
!Explanation
|-
| Pressure latitude || No || {{w|Pressure altitude|Pressure ''altitude''}} is the height above a standard datum plane, a theoretical level where the pressure of the atmosphere is 1013.24 millibars (29.921 inHg). It's essentially an estimate of altitude calculated from atmospheric pressure.
|-
| Enthalpic pressure || No || {{w|Enthalpy}} is the total internal energy of a thermodynamic system plus the product of the system's pressure and volume. Essentially, it represents the energy contained in a system, and is independent of the means or sequence of operations that the system went through to achieve its current state.
|-
| Entropic density || No || {{w|Entropy}} is a quantity that shows many physical processes can only go in one chronological direction. An egg can easily be scrambled (increasing its entropy), but it is very difficult to "un-scramble" an egg[[[285: Wikipedian Protester|''citation needed'']]][[Category:Pages using the "citation needed" template]] (which would decrease its entropy). Ordered systems have low entropy, with differences in temperature, pressure, potential energy, or the like. Disordered systems have high entropy, without temperature, pressure, electrical, or other differentials.
|-
| Latent heat of cooling || No || {{w|Latent heat}} is the energy absorbed or released by a system during a '''constant-temperature''' process, like melting, freezing, boiling, or condensing. Cooling is a process of lowering a temperature, and therefore not a constant-temperature process. The humor comes considering the "heat of cooling."
|-
| Isobars || Yes || Lines denoting equal ("{{wiktionary|iso-}}") air pressure ("{{wiktionary|bar-|-bar}}"), probably most often recognized as the indicators of how ground-level pressures change (or not) across the horizontal area depicted on a weather ''map''. In this type of chart, which depicts data obtained from above a single point, it has the same meaning but is instead a pre-existing reference line across which the actual data is plotted, and does not itself indicate the nature of any wind.
|-
| Omnitrophic wind || No || Something "omnitrophic" would apparently be "all-eating", in some scientific sense. An omnitrophic wind would probably be a concerning phenomenon.
Probably a play on something like {{w|geostrophic wind}} ("geo"+"strophic" being from "Earth curving"), a theoretical state of wind that results from an exact balance between the {{w|Coriolis force}} and the {{w|pressure gradient}} force.
|-
| Isomers || No || Different forms of molecules with the same formula, with the atoms or functional groups arranged differently. For example, propanol with the basic formula of C3H8O, or propane with a single -OH functional group attached. There are two distinct positions that the hydroxyl group can sit, 1-propanol has it at either end, while 2-propanol has it connected to the middle.
However, these are actually iso'''therm''' lines, representing equal temperature.
|-
| These lines are slightly different because Dave messed them up || No || Indicating isotherms (or, according to the comic, "isomers"), the suggestion is that slightly wrong lines were drawn by Dave and had to be corrected.
The real reason for the not quite identical lines is that the measured temperature at a given pressure can be converted to or from the ''potential'' temperature that the same air would have if at a standard pressure (holding the same amount of heat energy). For practical reasons, both for composing and interpreting the eventual plot, each of the slightly differently skewed isotherms are given, usually in clearly differentiable styles of line.

The "Dave" of the description may be David Bolton, whose [https://journals.ametsoc.org/view/journals/mwre/108/7/1520-0493_1980_108_1046_tcoept_2_0_co_2.xml 1980 paper] introduced a means of calculating the atmosphere's potential temperature.
|-
| Line of constant thermodynamics || No || {{w|Thermodynamics}} is a branch of physics concerned with work, temperature, heat, the way they relate to entropy, energy, enthalpy, and the physical properties of radiation and matter. As a field of study, Thermodynamics does not have '''constant lines,''' except perhaps as a means of describing a consistent avenue of research.
|-
| Uncomfortably moist adiabat || Wrongly placed, unusually qualified|| This labels a segment of isotherm, which is the exact 'opposite' of an adiabat.
An adiabat is a line along which temperature can change for a given mass, without changing the amount of energy. This is primarily made possible by changing the density (by a change in pressure) of the gas. There are typically two types of adiabat, marked for reference on the plot, "dry adiabat" (curves across the isotherms perpendicularly, to create a largely square but slightly curved grid with them), and "moist/saturated adiabat" (the latter's heat-maintaining profile is influenced greatly by the humidity content, and produces graphing lines vastly different from the equivalent "dry" versions). Randall has declared this (erroneous) type of adiabat to be "uncomfortably" moist, so presumably not totally saturated but also not subjectively 'pleasant'.
|-
| Oops, the balloon flew through a ghost || No || One of the purported effects of ghosts (such as in the film *The Sixth Sense*) is a transient/local lowering of temperature around and/or inside them. The line is interpreted as showing a local low temperature encountered at this pressure(/altitude).
This line, however, is probably the dew point line, indicating that in passing through this layer of the atmosphere, a drier band of air was encountered which would theoretically be cooled a lot more before the water-vapor oversaturates it and liquid water droplets form.
|-
| No birds up here :( || Yes* || This point is near the top of the diagram, with an air pressure of about 110 millibar - about 15 kilometers (50,000 feet) above sea level. This is well above the highest [https://peregrinefund.org/explore-raptors-species/vultures/ruppells-vulture flight height of any known bird species]. However, this information is irrelevant to the purpose of a skew-T log-P diagram.
|-
| Track of rising weather balloon || Yes, partially || Although there are other ways of recording these details, this is typically the record of a rising balloon.
However, it would be a track of the balloon through the varying pressures and temperatures that it records (as the second line of this type records the measurements of dew point at each pressure value). Moreover, circumstances that would make the recorded data plot out a neat {{w|figure-eight knot}} (see "Seems bad", below) are very unlikely.
|-
| Track of popped balloon falling back down || Possible, partially || A standard plot track will include two strong lines, as this has, representing not ''two'' balloons but the recorded temperature track ''and'' the dew point track, both against the (altitude surrogate) progressive pressure changes at each pressure-point.
A further pair of tracks as dotted lines could possibly be from a different launch (earlier, later or simultaneous from an adjacent location) as an analytical reference, but ''may'' indeed be the additional results obtained as the scientific package rapidly descends once the balloon pops.
|-
| Meteogenesis || No || The chart purports to show the path of two weather balloons crossing and labels the space between them with a new word. The root "meteo" means something high up (in this case, balloons) and "genesis" means creation. The implication is that a new balloon was created, though no third flight path is shown so it presumably did not fly separately or was not tracked.
In reality, one of the tracks (almost certainly the left one) is the track of the measured dew point. Where the line of the existing conditions cross this line is where the moisture will precipitate out and form clouds, a process that might well be called "{{wiktionary|meteor#English|meteo}}+{{wiktionary|genesis#English|genesis}}", but {{w|Cloud physics|isn't}}.
|-
| Seems bad || Not a common feature || The path of the balloon loops around in the shape of a {{w|figure-eight knot}}, which would indicate very chaotic conditions at that point, if taken as positional information
As the actual Skew-T Log-P graph does not record positional information, this is best interpreted as having encountered a fluctuating temperature as the pressure decreases, continuing as something (possibly {{w|Wind shear#Vertical component|vertical wind shear}}, or some form of compression waves, encountering the instruments) creates a temporary increase in external pressure, and then circumstances return it to its more typical altitude-induced pressure-drop. Though this is not ''impossible'' to naturally happen, it might even be best interpreted as the instruments being deliberately 'buzzed' by a passing aircraft or rocket, including some intermittent form of thermal backwash as the interfering craft criss-crosses the balloon's physical track in a briefly complex encounter.
 Whatever happened to the temperature/pressure track, it apparently did not significantly change the associated dew-point/pressure track (if the pressure did indeed temporarily rise, the related dew points repeated themselves each time the pressure values were re-encountered).
|-
| Dew point || Wrongly represented || The temperature at which water condenses out of the air, and therefore dew starts to form, given the amount of water vapor in the air. It is shown here as an ''actual'' single point, when it should be a line (typically the leftmost solid plotted line) representing the temperature at which dew should form at any given pressure.
|-
| Humidor || No || In reality, is a {{w|Humidor|container}} that is used to maintain a more controllable humidity within which to store smoking products. In the graph, points at the line that is probably representing the dew point, which is represents the ''actual'' humidity encountered.
|-
| Heavyside layer || No || In the metaphysical cosmology of the musical ''Cats'', the Heavyside Layer is a blissful afterlife which all the cats in the musical long for. It is likely included here as a comical misspelling of the {{w|Kennelly-Heaviside layer|(Kennelly-)Heaviside layer}} (also called the E region) of the {{w|ionosphere}} that was co-discovered by {{w|Arthur E. Kennelly}} and {{w|Oliver Heaviside}}. This layer is extremely far up in relative atmospheric terms, straddling the {{w|Kármán line|boundary to 'space'}}, and would be shown as a broad horizontal feature significantly above the existing "No birds up here" label, if it all.
The labeled item, in this diagram, is a heavily marked isotherm, or line of constant temperature. Most likely this is the 0°C line, marking the freezing point of water that is of great importance to meteorologists, pilots, etc. With a few caveats, passing 'through' this line marks a transition between any precipitation tending to be liquid rain and of it being snow/hail-forming (or, on passing down through it, to start melting such things), and if the measurement lines ''start'' above-left of this line then any falling (or condensing) water is almost certainly going to appear as one frozen form or other. Above-ground, it suggests important implications of potential ice-formation (affecting ''weight'' and lift dynamics) upon aircraft beyond any given altitude, should the existing moisture load be high and the dew-point be inconveniently close.
|-
| These lines are tilted because the wind is blowing them || No || The wind is not actually a derivable feature of this diagram, which does not have data of either direction or strength of air movement. These lines are actually dry adiabats (see above) — possibly two sets, due to a similar renormalized interpretation, as with the isotherms, at a given reference pressure.
|-
| Don't stand here or you might get hit by a balloon || No || On the misguided basis that this is a cross-sectional diagram, this would be the imagined release-point for the balloon(s) involved. And, if you're particularly (un)lucky with the winds, where they eventually fall straight back down to once the balloon has popped.
However, this is a diagram of some measurements ''for'' a location, not directly indicating a range of places you could choose to stand, and the bottom of the lines indicate the conditions ''at'' the release point (and possibly then the point of landing), regardless of where those lines appear to be rooted. To be accurate, the whole width of the table (and at a 'height' that represents the actual recorded ground-level pressure for that location and time) is where any 'danger' may be. The person initially releasing the balloon would not normally be too fazed by being struck by a wind-buffeted balloon (if anything, they'd be more concerned at damaging it prior to release). The attached remains of a popped balloon that is no longer buoyant will generally also act as a form of parachute (together with any actual drogue chute) to make any the light (and often well padded) payload descend slowly enough to not be a falling danger.
 Having traveled tens of kilometers up, before gently coming down, the chances of any given balloon landing in any given awkward spot (let alone the point of release) are low. Where possible, the sensor package and the remains of the balloon may be recovered, but the largest danger may instead be the environmental effects of the fragments of burst balloon, scattered to the very winds they were originally measuring.
|-
| Temperostrophic enthalpy (''Title text'') || No || The largely nonsensical first word perhaps could be interpreted as "time-warping", and allude to the varying passage of time experienced by those who do or do not understand these charts, on having to examine them.
|}

==Transcript==

:How to interpret a skew-T log-P diagram
:[The comic shows a skew-T log-P diagram. On it are various labels, including isobars, comments, and other interpretations of the diagram.]
:[Left to the diagram is an upwards-pointing arrow with the label "Pressure Latitude". Right to the diagram is a downwards-pointing arrow with the label "Entropic Density". Below the diagram is a right-pointing arrow with the label "Enthalpic Pressure".]
:[Two solid and dashed lines extend from the top line to the bottom line of the diagram.]
:[The remaining various labels are inside the diagram.]

:[Labels on the left:]
:[An arrow pointing to a densive dashed segment attaching to one solid line:] Latent heat of cooling
:[A label lying on one horizontal guide:] — Isobars —
:[An arrow pointing to the intersection of one solid and dashed line:] Omnitrophic wind
:[A label lying on one left-downward guide:] Isomers
:[A label lying on one right-downward guide:] Line of constant thermodynamics
:[An arrow pointing to a solid dashed segment on one left-downward guide:] Uncomfortably moist adiabat
:[An arrow pointing to the same solid line as ‘latent heat of cooling’:] Humidor
:[An arrow pointing to a steep peak on the same solid line:] Oops, the balloon flew through a ghost
:[To adjacent arrows pointing to two left-downward guide not perfectly coinciding to each other:] These lines are slightly different because Dave messed them up
:[An arrow pointing to the end of solid and dashed lines on the bottom line:] Don’t stand here or you might get hit by a balloon

:[Labels on the right:]
:[An arrow pointing to the top line:] No birds up here :(
:[An arrow pointing to one solid line generally:] Track of rising weather balloon
:[An arrow pointing to one dashed line generally:] Track of popped balloon falling back down
:[An arrow pointing to crossing of two solid lines, The area enclosed by which is painted black] Meteogenesis
:[An arrow pointing to a knot on one solid line:] Seems bad
:[An arrow pointing to a dot] Dew point
:[An arrow pointing to a highlighted left-downward guide:] Heavyside layer
:[Text written sideways below the line:] These lines are tilted because the wind is blowing them

==Trivia==
*Even though this comic was released on New Year's Day 2025, it was not a [[:Category:New Year|New Year comic]].
**Only second time this has happened since New Year comics became a regular thing from 2011.

{{comic discussion}}

[[Category:Charts]]
[[Category:Weather]]

3033: Origami Black Hole

2025-10-09T16:59:02Z

Giraffequeries: fixed transcript. may or may not be good

{{comic
| number = 3033
| date = January 3, 2025
| title = Origami Black Hole
| image = origami_black_hole_2x.png
| imagesize = 272x480px
| noexpand = true
| titletext = You may notice the first half of these instructions are similar to the instructions for a working nuclear fusion device. After the first few dozen steps, be sure to press down firmly and fold quickly to overcome fusion pressure.
}}

==Explanation==

This comic shows what at first appears to be an actual page of {{w|origami}} directions, like [https://origami.me/crane/ this one] or [https://origami.guide/origami-animals/origami-rabbits/origami-sleeping-rabbit/ this one], except labeled "How to fold a ''real'' origami black hole".

The "real" part draws a contrast to an origami ''depiction'' of a black hole. A piece of origami can be made to appear like one of the various images, diagrams, or artistic depictions of a black hole. It seems black-hole-like origami does exist, as created by [https://parchmentandallthingspaper.wordpress.com/2011/11/16/folding/ Richard Sweeney]. The implication is that while the linked origami only resembles a black hole, Randall's instructions create an actual {{w|black hole}} out of origami paper.

The instructions just repeat the operation of folding the paper in half, ignoring the increases in thickness and difficulty of folding that occur. In addition, the idea that one can create a black hole with one's bare hands is far-fetched. The difficult details in actually carrying out such a thing are left implied and unexplained - and they turn out to be surprisingly complex.

The number of folds is likely based on the {{w|Schwarzschild radius}} of a piece of paper. The Schwarzschild radius is a characteristic of every object that depends on the object's mass. If an object is compressed into the volume of a sphere with its characteristic Schwarzschild radius, then that object will become a black hole. (More specifically, it will become a {{w|Schwarzschild metric|Schwarzschild black hole}}.) As such, if a piece of paper were folded sufficiently many times so as to fit within its own Schwarzschild radius, it would become a black hole. However, this would require compressing the paper into a flat sheet at every step, as otherwise the folded paper would double in thickness at each step, greatly exceeding its Schwarzschild radius. Indeed, it would need to be compressed beyond the thinness of the original sheet of paper.

If we assume standard {{w|origami paper#Kami|kami origami paper}} with a side length of 15 cm and a weight of 70 grams per square meter, we get a mass of 1.575 grams, corresponding to a Schwarzschild radius of 2.339×10-30 meters. It follows that, ignoring the paper's thickness, we would need to halve each side length -log2((2 × 2.339×10-30 m)/0.15 m) = 94.69 times to fit each side length within the "Schwarzschild diameter" of the paper. Using the square folding technique in the comic, this would take 95 * 2 = 190 steps to complete, the exact number given in the comic. Note that the radius of the resulting black hole is 10-15 times the size of the {{w|Proton#Charge radius|charge radius of a proton}}. {{w|Micro black holes|Black holes this small}}, if they can be created at all, are believed to quickly disintegrate by losing energy via {{w|Hawking radiation}}. In this case, if those predictions are correct, it would result in an energy release equivalent to 33.8 kilotons of TNT, roughly equal to two atomic bombs dropped on Hiroshima, in approximately 1.57×10-28 seconds. (This is the energy equivalent of the mass of the paper, given by ''E'' = ''mc''2.)

In actual fact, it's not possible to fold a piece of paper this many times,{{cn}} because the amount of paper 'wasted' in each fold will quickly surpass the length and width of the paper. For an ordinary letter-sized (A4 or 8.5x11) sheet, the maximum number of folds is 7. The [https://www.guinnessworldrecords.com/world-records/494571-most-times-to-fold-a-piece-of-paper world record] for the total number of folds of a sheet of paper is 12, done with a length of tissue paper 3/4 mile (4000 ft, 1200 m) long. A group of MIT students demonstrated 13 folds using multiple miles of paper, but had to lay separate pieces together as it made them too thick to tape them. Materials other than paper, such as thin foil, can be folded more times. Not only that but, as the title text alludes, prior to reaching any creation of a black hole, the pressures generated by the resulting {{w|Nuclear fusion#Confinement in thermonuclear fusion|fusion of its atoms}} must be overcome. Electron and neutron degeneracy pressure would also have to be overcome.

Naively, the instructions would produce a paper stack of shrinking area, growing in thickness exponentially. This would become impossible long before the 190 folds in half that the instructions require. In fact, with a paper thickness of around 0.1 mm, for it to be possible to fold it 190 times, the sum of the lengths and width of the paper would need to be around 10110 meters, a good 1083 times the diameter of the observable universe.

The {{w|mathematics of paper folding}} were augmented with [https://web.archive.org/web/20051102085038/http://pomonahistorical.org/12times.htm work by a California high school student in 2001] who wrote equations that [https://web.archive.org/web/20211116013626/http://teachersofindia.org/sites/default/files/folding_paper_in_half.pdf related the size of paper to the maximum number of folds it could make], which has not yet exceeded the low teens in human competition. This could be exceeded by scoring the paper to cut and flatten the outer layers of the folds, but its thickness would immediately surpass its length, and compressing it beyond the size of its fibers would require some way to hold it together.

Since this folded paper would typically have growing thickness, the instructions wouldn't really create a black hole unless one somehow additionally compressed the paper commensurate with its decrease in width and length. Perhaps the comic imagines the folded paper retaining the same thickness as a single sheet; then the density and pressure required would likely reach a point where fusion between hydrogen atoms begins to occur (a la the very first ''[[what if? (blog)|what if?]]'' article, ''{{what if|1|Relativistic Baseball}}''). This is later alluded to in the title text.

==Transcript==
:How to fold a '''''real''''' origami black hole:

:Step 1.
:[A square sheet of paper with a dashed line going across the middle and an arrow pointing from one half to the other, indicating that it should be folded in that direction.]

:[In each step from Step 2. to Step 9., the paper is shown folded in half again and depicted in the same manner as Step 1. The aspect ratio of the sides alternates between 2:1 and 1:1.]
:Step 2.
:Step 3.
:Step 4.
:Step 5.
:Step 6.
:Step 7.
:Step 8.
:Step 9.

:Steps 10-189.
:[Text shown between tall square brackets:]
:Fold paper in half another 180 or so times.

:Step 190.
:[A labeled arrow points to an apparently glowing black dot]
:Black hole!

{{comic discussion}}

[[Category:Physics]]
[[Category:Astronomy]]

3088: Deposition

2025-10-09T13:52:53Z

Giraffequeries: fixed transcript, removed incomplete transcript tag

{{comic
| number = 3088
| date = May 12, 2025
| title = Deposition
| image = deposition_2x.png
| imagesize = 740x272px
| noexpand = true
| titletext = P.S. If you have time travel, come to my birthday party Saturday!
}}

==Explanation==
A {{w|continental margin}} is the place on the edge of a continent where the {{w|continental crust}} is underwater, covered by relatively shallow coastal waters. The scene is ambiguous, but it is feasible that Ponytail is standing on the back-shore {{w|littoral zone}} ''next'' to the rivermouth, such that she is actually {{tvtropes|LamePunReaction|a stone's throw}} away from the sea. As such, the stones she throws off to the right end up embedded directly into the soft shoreline/sediments without having to risk further erosion from all the other stones and gravel also sitting in the riverbed or being tumbled down it.

The continental margin is said to be {{w|passive margin|passive}}, which means that it is not currently undergoing [[:Category:Subduction|subduction]], where the oceanic crust slips under the continental crust, or a {{w|strike-slip fault}}, where one slides along the other, both of which can mechanically or thermally transform any seafloor material. Absent such occurrences, this causes piles of {{w|sediment}} to {{w|River delta#Formation|accumulate}} on the {{w|continental shelf}} with a minimum of additional geological disturbance.

This rock's eventual resting place in the sediment seems destined to be compressed by further overlying sedimentation and being solidified over geologic timescales into {{w|shale}} or other similar sedimentary rock types, presuming that the future movement of further sediment and relative local changes of sea-level and shoreline keep adding more material. As shown, 100 million years later, the sea level has gone down (and/or the bedrock has risen), re-exposing the strata. Recent erosion/quarrying has caused it to become a cliff face that eventually re-exposes the original rock that Ponytail threw into the river, apparently just at the right time and place to be discovered or uncovered by [[2990: Late Cenozoic|aliens/far-future-earthlings]].

These beings appear to be digging with relatively primitive hand-tools that are strangely anthropocentric and relatively inefficient, given the apparent use of antigravity personal conveyors with mechanical manipulators, and have found a rock. Whether or not they fully comprehend it, this seems to be one of those left with a still visible carved message by Ponytail, saying "This bedrock inspected by No. 5". This is a parody of a typical {{w|quality control}} label left attached to (or hidden within) clothing, to reassure any purchaser and/or help identify which manufacturing and inspection path any newly discovered {{w|product defect}} had passed through.

In the title text, Ponytail has added a {{w|postscript}} (whether on the same stone or a separate one is unclear) suggesting that the aliens/future-earth-based-lifeforms may have access to {{w|time travel}} technology, and inviting them to her birthday party (next) Saturday. The invitation does not seem to give an indication when it was written, and therefore ''which'' Saturday is meant, so, even if the finders were able to time travel, it might still be non-trivial for them to attend the birthday party. This also presupposes that the future discoverers understand the concept of the seven-day week cycle and have no trouble reading the invite, both remaining legible and not requiring impractical levels of translation from "ancient English". It may also be referencing the {{w|time travel party}} held by Stephen Hawking, in which he held a party which he hoped time travelers would attend. Hawking released invitations to the party only the following day, so only a time traveler would be able to attend the party.

==Transcript==

:[Cueball approaches a kneeling Ponytail, chiselling a rock on a grassy shoreline next to a river with shallow rolling hills in the background]
:Cueball: What are you doing?
:Ponytail: This river empties onto a passive continental margin.

:[Cueball and Ponytail stand talking, Ponytail holding several flat rocks, in an otherwise empty and frameless panel]
:Ponytail: If I chisel notes onto these rocks and throw them into the sea, they might be incorporated into some shale cliff in the distant future.

:[Silhouetted scene of Ponytail as she throws multiple rocks into the off-frame river to the right, Cueball watching from behind her]
:[From off-panel, sound effect of a rock hitting water:] PLOP

:[Two aliens with snail-like eyestalks and large eyes, with mechanical lower bodies resembling small flying saucers look rightwards at an exposed rock-face. A pick and shovel are left stuck in the ground, and the right alien's saucer sports a mechanical arm currently holding a loose fragment of rock. There are three question marks above the alien on the left and two question marks next to the alien on the right]
:[Panel label:] 100 million years later...
:[Text originating from the held rock fragment:] This bedrock inspected by No. 5

{{comic discussion}}<noinclude>
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Geology]]
[[Category:Aliens]]
[[Category:Time travel]]

2056: Horror Movies

2025-08-29T20:28:12Z

Giraffequeries: fixed some grammar and caps mistakes

{{comic
| number = 2056
| date = October 8, 2018
| title = Horror Movies
| image = horror_movies.png
| titletext = "Isn't the original Jurassic Park your favorite movie of all time?" "Yes, but that's because I like dinosaurs and I WANT there to be an island full of them. If John Hammond's lab had been breeding serial killers in creepy masks, I wouldn't have watched!" "Wait, are you sure? That could actually be good." "Ok, I WOULD watch the scenes where Jeff Goldblum tries to convince a bunch of executives that the park is a bad idea."
}}

==Explanation==
This comic was followed by [[2076: Horror Movies 2]] a month later. {{w|Horror_film|Horror movies}} are a {{w|Film_genre|genre}} of {{w|movie|movie or film}} which generally center around eliciting fear in the viewer. Such films have gone through cycles of rising and falling popularity, and were particularly popular at this time of this strip's release. When [[White Hat]] suggests watching such a movie, [[Cueball]] sarcastically responds "Sure! I love watching terrible things happen to people and feeling afraid!" This presumably reflects the reasons why Cueball is uninterested in watching horror films, and why he finds the appeal incomprehensible. The caption reveals that this is also true of [[Randall]].

The emotional response of fear, by its nature, tends to repel people. The biological purpose of the fear response is to signal that you are in danger, and should find a way out of the situation. Accordingly, the fact that people would deliberately seek out (and remain in) situations that they're afraid of is counterintuitive. Nonetheless, there are many activities which are pursued for entertainment which are specifically designed to trigger a fear response. The reasons for this are varied and speculative. The emotion of fear, and its accompanying physical responses (racing pulse, rapid breath, adrenaline release) are appealing and thrilling to some. Experiencing the response without facing genuine danger allows people to experience and explore fear in a safe environment. For some people, this might have a {{w|catharsis|cathartic effect}}, giving them control over the release of their emotions. For some, it could act as a form of {{w|exposure therapy}}, allowing them to reduce exaggerated fear responses. Others take a more detached view and enjoy watching bad things happen to other people, perhaps deriving humor or enjoyment out of a situation that they are glad not to be in themselves (and with the additional protection of knowing that the events aren't real).

Neither Cueball nor Randall seem to connect with any of the things that make horror films appealing to some, and experience it only as a negative and revulsive experience. As a result, both are entirely uninterested in seeking them out as entertainment.

The title text continues the conversation. White Hat points out that Cueball's favorite movie is {{w|Jurassic Park (film)|Jurassic Park}}. This movie could be considered a "horror" film, since a significant portion of the film consists of people fleeing in terror and trying to survive as dinosaurs hunt and kill them. Randall makes the distinction that he ''likes'' dinosaurs and ''wants'' there to be an island full of them, hence, rather than being a source of fear, he sees the narrative as something appealing. He says that if the company in the film had been breeding "serial killers in creepy masks", he wouldn't have watched. The implication is that people being hunted by serial killers is revulsive to him, but people being hunted by dinosaurs is not (implicitly because he sympathizes with the dinosaurs more than with the people).

The conversation then goes off the rails a bit, as White Hat argues that the plot Cueball suggests "could actually be good". The notion of a lab specifically breeding serial killers might make for a viable horror movie, but Cueball has expressed his dislike for the genre, and replies that he'd only watch the scene where Jeff Goldblum tries to convince executives that it's a bad idea. An early scene in Jurassic Park has {{w|Ian Malcolm (Jurassic Park character)|Ian Malcolm}}, played by {{w|Jeff Goldblum}}, trying (unsuccessfully) to convince the executives of the park that breeding dinosaurs in the modern age is an incredibly dangerous notion, since the outcomes are impossible to predict, and no safety measures can account for all the possible outcomes. The joke is that the notion of breeding serial killers for an amusement park is even more obviously terrible than breeding dinosaurs, and the idea of watching the same character trying to make that case (and presumably being ignored) is appealing to Cueball, even if the rest of the movie wouldn't be.

==Transcript==
:[White Hat and Cueball are standing together and talking. White Hat points at Cueball who has raised his arms.]
:White Hat: Wanna see a horror movie?
:Cueball: Sure! I love watching terrible things happen to people and feeling afraid!

:[Caption below the frame:]
:I know everyone's into what they're into, but I have never understood horror movies.

== Trivia ==
In early issues, [[Randall]] frequently referenced his fear of [[:Category:Velociraptors|velociraptors]] based on watching Jurassic Park as a kid.

{{comic discussion}}

[[Category:Comics sharing name|Horror Movies 01]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Fiction]]
[[Category:Jurassic Park]]
[[Category:Dinosaurs]]
[[Category:Movies]]
[[Category:Horror Movies]]

3118: iNaturalist Animals and Plants

2025-08-22T19:23:40Z

Giraffequeries: Transcript looked pretty okay to me, removed the incomplete tag. If anyone wants to put the tag on there again, please put a reason for why it's incomplete and I'll do my best to fix the problem ;)

{{comic
| number = 3118
| date = July 21, 2025
| title = iNaturalist Animals and Plants
| image = inaturalist_animals_and_plants_2x.png
| imagesize = 740x508px
| noexpand = true
| titletext = Washington, DC: Eastern gray squirrel, Amur honeysuckle. Puerto Rico: Crested anole, sea grape. US as a whole: Mallard, eastern poison ivy.
}}

==Explanation==
This comic is a map of the United States showing, for each state, the name of the animal and plant most commonly reported on the {{w|citizen science}} social network {{w|iNaturalist}}. As the comic notes, these are not the most-encountered species, just the ones reported the most on iNaturalist. iNaturalist is a citizen science social network that shares observations of nature. In some cases the species most reported is an invasive species causing concern, such as brown anole and Amur honeysuckle, while some local species which are actually the most present and observable may escape being fully reported by not being considered worthy of any note.

For some smaller states, the animal and plant names are listed outside the state, with a connector line to the state. Some non-state regions are covered in the title text: the {{w|District of Columbia}}, too small to list such information on the district itself and in an awkward location for a connector; {{w|Puerto Rico}}, an unincorporated U.S. territory with a large population outside the 50 standard states (both contiguous and otherwise); and the U.S. as a whole.

The most reported animals are Common Eastern Bumble Bee and White-tailed Deer, with 7 states each, while the most reported plant is Common Milkweed, with 6 states. Of the 26 different animal species mentioned, 5 are mammals, 4 are birds, 12 are reptiles, and 5 are insects. This is part of what makes the results for "US as a whole" surprising: they only top the list in one or two states, yet become the most reported when adding up the numbers nationwide.

iNaturalist community members have [https://forum.inaturalist.org/t/today-s-xkcd-comic-is-about-inaturalist/67916 noted] that several species have made it on the list due to a few prolific contributors contributing large numbers of observations of the same species.

===Reference table===
{| class="wikitable sortable"
! colspan="2" rowspan="2"| State
! colspan="2" | Most observed...
|-
!Animal
!Plant
|-
!AL
|{{w|Alabama}}
|{{w|Gulf fritillary}}
|{{w|Liquidambar styraciflua|American Sweetgum}}
Also in: '''[[#GA|GA]]''', '''[[#SC|SC]]'''
|-
!AK
|{{w|Alaska}}
|{{w|Moose}}
|{{w|Chamaenerion angustifolium|Fireweed}}
|-
!AZ
|{{w|Arizona}}
|{{w|Urosaurus ornatus|Ornate Tree Lizard}}
''(Also the State Animal of Nebraska)''
|{{w|Saguaro}}
|-
!AR
|{{w|Arkansas}}
|{{w|Three-toed box turtle}}
''(Official Reptile of Missouri)''
|{{w|Ligustrum sinense|Chinese Privet}}
'''Naturalized'''
|-
!CA
|{{w|California}}
|{{w|Western fence lizard}}
|{{w|Eschscholzia californica|California Poppy}}
|-
!CO
|{{w|Colorado}}
|{{w|Mule deer}}
Also in: '''[[#NM|NM]]''', '''[[#OR|OR]]''', '''[[#UT|UT]]'''
|{{w|Verbascum thapsus|Great Mullein}}
'''Invasive'''
|-
!CT
|{{w|Connecticut}}
|{{w|Bombus impatiens|Common Eastern Bumble Bee}}
Also in: '''[[#IL|IL]]''', '''[[#MA|MA]]''', '''[[#MD|MD]]''', '''[[#MN|MN]]''', '''[[#VT|VT]]''', '''[[#WI|WI]]'''
|{{w|Chimaphila maculata|Striped Wintergreen}}
|-
!DE
|{{w|Delaware}}
|{{w|Anaxyrus fowleri|Fowler's Toad}}
|{{w|Phytolacca americana|American Pokeweed}}
|-
!FL
|{{w|Florida}}
|{{w|Brown Anole}}
'''Invasive'''
|{{w|Bidens alba|White Beggar-ticks}}
|-
!GA
|{{w|Georgia (U.S. state)|Georgia}}
|{{w|Anolis carolinensis|Green Anole}}
Also in: '''[[#LA|LA]]'''
|American Sweetgum
Also in: '''[[#AL|AL]]''', '''[[#SC|SC]]'''
|-
!HI
|{{w|Hawaii}}
|{{w|Green sea turtle}}
|{{w|Metrosideros polymorpha|ʻŌhiʻa Lehua}}
'''Endangered'''
|-
!ID
|{{w|Idaho}}
|{{w|Mallard}}
Also in: '''[[#WA|WA]]''', '''[[#**|Whole US]]'''
|{{w|Artemisia tridentata|Big Sagebrush}}
|-
!IL
|{{w|Illinois}}
|Common Eastern Bumble Bee
Also in: '''[[#CT|CT]]''', '''[[#MA|MA]]''', '''[[#MD|MD]]''', '''[[#MN|MN]]''', '''[[#VT|VT]]''', '''[[#WI|WI]]'''
|{{w|Asclepias syriaca|Common Milkweed}}
Also in: '''[[#IA|IA]]''', '''[[#MI|MI]]''', '''[[#MN|MN]]''', '''[[#NE|NE]]''', '''[[#WI|WI]]'''
|-
!IN
|{{w|Indiana}}
|{{w|American robin}}
Also in: '''[[#NE|NE]]''', '''[[#TN|TN]]'''
|{{w|Lonicera maackii|Amur Honeysuckle}}
Also in: '''[[#DC|DC]]''', '''[[#KS|KS]]''', '''[[#KY|KY]]''', '''[[#MO|MO]]

'''Invasive'''
|-
!IA
|{{w|Iowa}}
|{{w|White-tailed deer}}
Also in: '''[[#MI|MI]]''', '''[[#MT|MT]]''', '''[[#NH|NH]]''', '''[[#PA|PA]]''', '''[[#VA|VA]]''', '''[[#WV|WV]]'''
|Common Milkweed
Also in: '''[[#IL|IL]]''', '''[[#MI|MI]]''', '''[[#MN|MN]]''', '''[[#NE|NE]]''', '''[[#WI|WI]]'''
|-
!KS
|{{w|Kansas}}
|{{w|Ornate box turtle}}
|Amur Honeysuckle
Also in: '''[[#DC|DC]]''', '''[[#IN|IN]]''', '''[[#KS|KS]]''', '''[[#MO|MO]]

'''Invasive'''
|-
!KY
|{{w|Kentucky}}
|{{w|Common box turtle}}
'''Vulnerable'''
|Amur Honeysuckle
Also in: '''[[#DC|DC]]''', '''[[#IN|IN]]''', '''[[#KS|KS]]''', '''[[#MO|MO]]

'''Invasive'''
|-
!LA
|{{w|Louisiana}}
|Green Anole
Also in: '''[[#GA|GA]]'''
|{{w|Taxodium distichum|Bald Cypress}}
|-
!ME
|{{w|Maine}}
|{{w|American herring gull}}
Also in: '''[[#RI|RI]]'''
|{{w|Cornus canadensis|Canadian Bunchberry}}
|-
!MD
|{{w|Maryland}}
|Common Eastern Bumble Bee
Also in: '''[[#CT|CT]]''', '''[[#IL|IL]]''', '''[[#MA|MA]]''', '''[[#MN|MN]]''', '''[[#VT|VT]]''', '''[[#WI|WI]]'''
|{{w|Pinus strobus|Eastern White Pine}}
Also in: '''[[#MA|MA]]''', '''[[#NH|NH]]''', '''[[#VT|VT]]'''
|-
!MA
|{{w|Massachusetts}}
|Common Eastern Bumble Bee
Also in: '''[[#CT|CT]]''', '''[[#IL|IL]]''', '''[[#MD|MD]]''', '''[[#MN|MN]]''', '''[[#VT|VT]]''', '''[[#WI|WI]]'''
|Eastern White Pine
Also in: '''[[#MD|MD]]''', '''[[#NH|NH]]''', '''[[#VT|VT]]'''
|-
!MI
|{{w|Michigan}}
|White-tailed Deer
Also in: '''[[#IA|IA]]''', '''[[#MT|MT]]''', '''[[#NH|NH]]''', '''[[#PA|PA]]''', '''[[#VA|VA]]''', '''[[#WV|WV]]'''
|Common Milkweed
Also in: '''[[#IA|IA]]''', '''[[#IL|IL]]''', '''[[#MN|MN]]''', '''[[#NE|NE]]''', '''[[#WI|WI]]'''
|-
!MN
|{{w|Minnesota}}
|Common Eastern Bumble Bee
Also in: '''[[#CT|CT]]''', '''[[#IL|IL]]''', '''[[#MA|MA]]''', '''[[#MD|MD]]''', '''[[#VT|VT]]''', '''[[#WI|WI]]'''
|Common Milkweed
Also in: '''[[#IA|IA]]''', '''[[#IL|IL]]''', '''[[#MI|MI]]''', '''[[#NE|NE]]''', '''[[#WI|WI]]'''
|-
!MS
|{{w|Mississippi}}
|{{w|Northern cardinal}}
Also in: '''[[#SC|SC]]''', '''[[#TX|TX]]'''
|{{w|Sarracenia alata|Pale Pitcher Plant}}
|-
!MO
|{{w|Missouri}}
|{{w|Bombus griseocollis|Brown-belted Bumble Bee}}
|Amur Honeysuckle
Also in: '''[[#DC|DC]]''', '''[[#IN|IN]]''', '''[[#KS|KS]]''', '''[[#KY|KY]]

'''Invasive'''
|-
!MT
|{{w|Montana}}
|White-tailed Deer
Also in: '''[[#IA|IA]]''', '''[[#MI|MI]]''', '''[[#NH|NH]]''', '''[[#PA|PA]]''', '''[[#VA|VA]]''', '''[[#WV|WV]]'''
|{{w|Achillea millefolium|Common Yarrow}}
|-
!NE
|{{w|Nebraska}}
|American Robin
Also in: '''[[#IN|IN]]''', '''[[#TN|TN]]'''
|Common Milkweed
Also in: '''[[#IA|IA]]''', '''[[#IL|IL]]''', '''[[#MI|MI]]''', '''[[#MN|MN]]''', '''[[#WI|WI]]'''
|-
!NV
|{{w|Nevada}}
|{{w|Common side-blotched lizard}}
|{{w|Larrea tridentata|Creosote Bush}}
Also in: '''[[#NM|NM]]'''
|-
!NH
|{{w|New Hampshire}}
|White-tailed Deer
Also in: '''[[#IA|IA]]''', '''[[#MI|MI]]''', '''[[#MT|MT]]''', '''[[#PA|PA]]''', '''[[#VA|VA]]''', '''[[#WV|WV]]'''
|Eastern White Pine
Also in: '''[[#MA|MA]]''', '''[[#MD|MD]]''', '''[[#VT|VT]]'''
|-
!NJ
|{{w|New Jersey}}
|{{w|Spotted lanternfly}}
'''Invasive'''
|{{w|Artemisia vulgaris|Common Mugwort}}
'''Invasive native'''
|-
!NM
|{{w|New Mexico}}
|Mule Deer
Also in: '''[[#CO|CO]]''', '''[[#OR|OR]]''', '''[[#UT|UT]]'''
|Creosote Bush
Also in: '''[[#NV|NV]]'''
|-
!NY
|{{w|New York (state)|New York}}
|{{w|Eastern gray squirrel}}
Also in: '''[[#DC|DC]]''', '''[[#NC|NC]]

''(Invasive to Europe)''
|{{w|Ageratina altissima|White Snakeroot}}
|-
!NC
|{{w|North Carolina}}
|Eastern Gray Squirrel
Also in: '''[[#DC|DC]]''', '''[[#NY|NY]]'''
|{{w|Polystichum acrostichoides|Christmas Fern}}
Also in: '''[[#TN|TN]]'''
|-
!ND
|{{w|North Dakota}}
|{{w|American bison}}
Also in: '''[[#SD|SD]]''', '''[[#WY|WY]]'''
|{{w|Rosa arkansana|Prairie}} {{w|Rosa blanda|Rose}}
''(Could be one of several {{w|Prairie Rose}} species.)''
|-
!OH
|{{w|Ohio}}
|{{w|Erythemis simplicicollis|Eastern Pondhawk}}
|{{w|Claytonia virginica|Virginia Springbeauty}}
|-
!OK
|{{w|Oklahoma}}
|{{w|Pond slider}}
|{{w|Juniperus virginiana|Eastern Redcedar}}
|-
!OR
|{{w|Oregon}}
|Mule Deer
Also in: '''[[#CO|CO]]''', '''[[#NM|NM]]''', '''[[#UT|UT]]'''
|{{w|Pinus ponderosa|Western Ponderosa Pine}}
''("Western" yellow-pine, a.k.a. "Ponderosa" pine?)''
|-
!PA
|{{w|Pennsylvania}}
|White-tailed Deer
Also in: '''[[#IA|IA]]''', '''[[#MI|MI]]''', '''[[#MT|MT]]''', '''[[#NH|NH]]''', '''[[#VA|VA]]''', '''[[#WV|WV]]'''
|{{w|Alliaria petiolata|Garlic Mustard}}
'''Invasive'''
|-
!RI
|{{w|Rhode Island}}
|American Herring Gull
Also in: '''[[#ME|ME]]'''
|{{w|Rosa rugosa|Rugosa Rose}}
|-
!SC
|{{w|South Carolina}}
|Northern Cardinal
Also in: '''[[#MS|MS]]''', '''[[#TX|TX]]'''
|American Sweetgum
Also in: '''[[#AL|AL]]''', '''[[#GA|GA]]'''
|-
!SD
|{{w|South Dakota}}
|American Bison
Also in: '''[[#ND|ND]]''', '''[[#WY|WY]]'''
|{{w|Verbena stricta|Hoary Vervain}}
|-
!TN
|{{w|Tennessee}}
|American Robin
Also in: '''[[#IN|IN]]''', '''[[#NE|NE]]'''
|Christmas Fern
Also in: '''[[#NC|NC]]'''
|-
!TX
|{{w|Texas}}
|Northern Cardinal
Also in: '''[[#MS|MS]]''', '''[[#SC|SC]]'''
|{{w|Oenothera speciosa|Pinkladies}}
|-
!UT
|{{w|Utah}}
|Mule Deer
Also in: '''[[#CO|CO]]''', '''[[#NM|NM]]''', '''[[#OR|OR]]'''
|{{w|Juniperus osteosperma|Utah Juniper}}
|-
!VT
|{{w|Vermont}}
|Common Eastern Bumble Bee
Also in: '''[[#CT|CT]]''', '''[[#IL|IL]]''', '''[[#MA|MA]]''', '''[[#MD|MD]]''', '''[[#MN|MN]]''', '''[[#WI|WI]]'''
|Eastern White Pine
Also in: '''[[#MA|MA]]''', '''[[#MD|MD]]''', '''[[#NH|NH]]'''
|-
!VA
|{{w|Virginia}}
|White-tailed Deer
Also in: '''[[#IA|IA]]''', '''[[#MI|MI]]''', '''[[#MT|MT]]''', '''[[#NH|NH]]''', '''[[#PA|PA]]''', '''[[#WV|WV]]'''
|{{w|Toxicodendron radicans|Eastern Poison Ivy}}
Also in: '''[[#**|Whole US]]'''
|-
!WA
|{{w|Washington (state)|Washington}}
|Mallard
Also in: '''[[#ID|ID]]''', '''[[#**|Whole US]]'''
|{{w|Polystichum munitum|Western Sword Fern}}
|-
!WV
|{{w|West Virginia}}
|White-tailed Deer
Also in: '''[[#IA|IA]]''', '''[[#MI|MI]]''', '''[[#MT|MT]]''', '''[[#NH|NH]]''', '''[[#PA|PA]]''', '''[[#VA|VA]]'''
|{{w|Rhododendron maximum|Great Rhododendron}}
|-
!WI
|{{w|Wisconsin}}
|Common Eastern Bumble Bee
Also in: '''[[#CT|CT]]''', '''[[#IL|IL]]''', '''[[#MA|MA]]''', '''[[#MD|MD]]''', '''[[#MN|MN]]''', '''[[#VT|VT]]'''
|Common Milkweed
Also in: '''[[#IA|IA]]''', '''[[#IL|IL]]''', '''[[#MI|MI]]''', '''[[#MN|MN]]''', '''[[#NE|NE]]'''
|-
!WY
|{{w|Wyoming}}
|American Bison
Also in: '''[[#ND|ND]]''', '''[[#SD|SD]]'''
|{{w|Geranium viscosissimum|Sticky Geranium}}
|- bgcolor="#eeeeee"
!DC
|{{w|Washington, D.C.|Washington DC}} ''(title text)''
|Eastern gray squirrel
Also in: '''[[#NC|NC]]''', '''[[#NY|NY]]'''
|Amur Honeysuckle
Also in: '''[[#IN|IN]]''', '''[[#KS|KS]]''', '''[[#KY|KY]]''', '''[[#MO|MO]]

'''Invasive'''
|- bgcolor="#eeeeee"
!PR
|{{w|Puerto Rico}} ''(title text)''
|{{w|Anolis cristatellus|Crested anole}}
|{{w|Coccoloba uvifera|Sea grape}}
|- bgcolor="#eeeeee"
!data-sort-value="**"|
|{{w|United States|'''US as a whole'''}} ''(title text)''
|Mallard
Also in: '''[[#WA|WA]]''', '''[[#ID|ID]]'''
|Eastern poison ivy
Also in: '''[[#VA|VA]]'''
|}

==Transcript==
:[The comic shows a map of the United States with state borders (including Hawaii and Alaska inset in the lower left) and two-letter state codes for each state. The map includes the Northwest Angle, which is not typically shown on maps of this scale.]
:[Above the map]: The Most-Observed Animal and Plant in Each State on iNaturalist
:[Below that, in parentheses]: Not the most common species in the state, just the one people have reported the most times.
:[Each state has text of the format "Animal" on top and "Plant" below. For RI, VT, NH, MA, CT, NJ, DE, and MD, the text is outside the state border with a line connecting them.]

:[In alphabetical order, the states have the following Animal/Plant text]:

:Alabama: Gulf Fritillary; American Sweetgum 
:Alaska: Moose; Fireweed 
:Arizona: Ornate Tree Lizard; Saguaro 
:Arkansas: Three-toed Box Turtle; Chinese Privet 
:California: Western Fence Lizard; California Poppy 
:Colorado: Mule Deer; Great Mullein 
:Connecticut: Common Eastern Bumble Bee; Striped Wintergreen 
:Delaware: Fowler's Toad; American Pokeweed 
:Florida: Brown Anole; White Beggar-ticks 
:Georgia: Green Anole; American Sweetgum 
:Hawaii: Green Sea Turtle; ʻŌhiʻa Lehua 
:Idaho: Mallard; Big Sagebrush 
:Illinois: Common Eastern Bumble Bee; Common Milkweed 
:Indiana: American Robin; Amur Honeysuckle 
:Iowa: White-tailed Deer; Common Milkweed 
:Kansas: Ornate Box Turtle; Amur Honeysuckle 
:Kentucky: Common Box Turtle; Amur Honeysuckle 
:Louisiana: Green Anole; Bald Cypress 
:Maine: American Herring Gull; Canadian Bunchberry 
:Maryland: Common Eastern Bumble Bee; Eastern White Pine 
:Massachusetts: Common Eastern Bumble Bee; Eastern White Pine 
:Michigan: White-tailed Deer; Common Milkweed 
:Minnesota: Common Eastern Bumble Bee; Common Milkweed 
:Mississippi: Northern Cardinal; Pale Pitcher Plant 
:Missouri: Brown-belted Bumble Bee; Amur Honeysuckle 
:Montana: White-tailed Deer; Common Yarrow 
:Nebraska: American Robin; Common Milkweed 
:Nevada: Common Side-blotched Lizard; Creosote Bush 
:New Hampshire: White-tailed Deer; Eastern White Pine 
:New Jersey: Spotted Lanternfly; Common Mugwort 
:New Mexico: Mule Deer; Creosote Bush 
:New York: Eastern Gray Squirrel; White Snakeroot 
:North Carolina: Eastern Gray Squirrel; Christmas Fern 
:North Dakota: American Bison; Prairie Rose 
:Ohio: Eastern Pondhawk; Virginia Springbeauty 
:Oklahoma: Pond Slider; Eastern Redcedar 
:Oregon: Mule Deer; Western Ponderosa Pine 
:Pennsylvania: White-tailed Deer; Garlic Mustard 
:Rhode Island: American Herring Gull; Rugosa Rose 
:South Carolina: Northern Cardinal; American Sweetgum 
:South Dakota: American Bison; Hoary Vervain 
:Tennessee: American Robin; Christmas Fern 
:Texas: Northern Cardinal; Pinkladies 
:Utah: Mule Deer; Utah Juniper 
:Vermont: Common Eastern Bumble Bee; Eastern White Pine 
:Virginia: White-tailed Deer; Eastern Poison Ivy 
:Washington: Mallard; Western Sword Fern 
:West Virginia: White-tailed Deer; Great Rhododendron 
:Wisconsin: Common Eastern Bumble Bee; Common Milkweed 
:Wyoming: American Bison; Sticky Geranium 

==Trivia==
*In the [https://www.explainxkcd.com/wiki/images/archive/c/c9/20250723151925%21inaturalist_animals_and_plants_2x.png original version of the comic], the postal codes for Iowa, Florida, Alaska, and Hawaii were missing from the map. They were later added.

{{comic discussion}}<noinclude>

[[Category:Comics edited after their publication]]
[[Category:Animals]]
[[Category:Biology]]
[[Category:US maps]]
[[Category:Turtles]]

Talk:Blue Eyes

2025-08-22T00:48:19Z

Giraffequeries:

Why is this in [[:Category:My_Hobby|My Hobby]]? Like, what's the hobby? [[User:Giraffequeries|Giraffequeries]] ([[User talk:Giraffequeries|talk]]) 00:48, 22 August 2025 (UTC)

Is it really incomplete on the grounds that Joel hasn't be identified? Explanations of comics 57-59 leave no more explanation of "Scott" than that he appears to be Randall's friend. The fact that we don't have a last name for him doesn't make either [[Scott]] or those comic explanations incomplete. Similarly, not have a full identifier for "Joel" in this one doesn't, in my opinion, warrant an incomplete tag. I'm removing the tag. If anyone object, revert it. [[User:Djbrasier|Djbrasier]] ([[User talk:Djbrasier|talk]]) 19:22, 22 May 2015 (UTC)

The proof for this puzzle is incomplete, if not wrong. The theorem is too weak, it should be: "Theorem: N blue eyed people with Nth order knowledge of all N people being logicians, N people having blue eyes, and any blue eyed person will leave as soon as possible after deducing they have blue eyes, will be able to leave on the Nth day." This may seem pedantic, but it really gets to the heart of the problem, which is trying to illustrate the use of orders of knowledge. In the theorem as stated, just N blue eyed people will leave on the Nth day, the proof for the inductive steps does not hold. You need to further assume that the person is able to deduce the hypothesis (which should be proven). In other words, you say X-1 people would leave on the (X-1)th day by hypothesis, so the Xth person knows he can leave on the Xth day. But you did not prove that the Xth person can actually deduce this, namely that he has all the information necessary to do so. In the correctly stated hypothesis, you then need to show that N + 1 people with (N+1)th order knowledge of all those things can deduce that the N people would leave if it was just them, and further that N+1 people have (N+1)th order knowledge of all these things. This is very important, and holds true (Since N+1th order knowledge is equivalent to knowing the N people have the Nth order knowledge necessary to fulfill the hypothesis, and by symmetry if the N logicians can figure it out the (N+1)th can too. Also, they have (N+1)th order knowledge of people leaving as soon as they can and everyone being a logician since in the proper statement of the puzzle it should be noted this is common knowledge, and the guru makes the knowledge of someone having blue eyes common knowledge.). Then you have a full proof, since you have now included that they can actually deduce the inductive step. Again, this may seem pedantic, but is really necessary both to be correct and as it illustrates the key of the puzzle, namely the guru gives 100th order knowledge of someone having blue eyes (this is the main problem people have, realizing the concrete piece of information the guru gives). [[User:Jlangy|Jlangy]] ([[User talk:Jlangy|talk]]) 00:29, 9 July 2015

What I don't follow here is that there's no clarification that the Guru is talking about someone different each time. Just because she says "I see someone with blue eyes" N times doesn't mean that there are N people with blue eyes; she could be talking about the same person every time, or each of two people half the time, etc. Can anyone clarify this?
Thanks - [[Special:Contributions/108.162.218.47|108.162.218.47]] 13:20, 28 October 2015 (UTC)

^^^ The Guru speaks only once on the first day and then is silent the rest of the time. --[[Special:Contributions/172.69.22.125|172.69.22.125]] 00:18, 10 December 2023 (UTC)

(EDIT: Observe the process of comprehension in action...or don't? I've been thinking about my own brain, with itself, long enough for one day, I'm tired.)
So, maybe I am indeed just "dumb", as the wiki insists. Clearly, I do not have a perfect understanding of formal logic. But frankly, my read of this puzzle is that "formal logic" just enables you to jump to ridiculous conclusions.
Let's theorize a simpler version of this puzzle. There are now only two people besides the Guru on the island, both with blue eyes. We'll call them Bill and Ted (totally bogus, I know). No matter how logical Bill and Ted might be, when Bill hears the Guru say "I see a person with blue eyes" to himself and Ted, and Bill has seen Ted's blue eyes himself, why would Bill assume anything about his own eye color? It would seem to Bill that Guru was just talking about Ted's eyes, and Ted would believe the reverse. Even knowing* that Ted would leave that night if Ted deduced he had blue eyes too, I still don't see why Bill would jump to the conclusion that the Guru was talking about him - he remains in the dark, as does Ted, and neither of them can be any more certain of anything than they previously were. Adding 98 more blue-eyed people, let alone doubling the island's population with irrelevant brown-eyers, hardly reduces the confusion.
* This was the point at which I began to think I had understood it, but then I became unsure again. Like I said in the "edit", my brain is tired.
--So, that settles it, I do not understand how the puzzle can be true, and I'm not convinced that it actually is. Knowing Randall is, in general, smarter than me...I still do not have the ability to completely accept that he's always right, or that I'm always wrong to ignorantly question his rightness. I have long maintained that certain well-respected "systems of knowledge", of which formal logic is a textbook example, have been respected too well for too long for not-good-enough reasons. To me, they seem to be founded on an assumption which is itself founded on nothing. I'm not trying to insult Randall or anyone else, I'm just utterly failing to comprehend. I will appreciate if anyone else attempts to educate me on the subject, but I may prove an intractable student, since I am unable to extend much faith or trust (or even, on a day where my mood is worse than today, the moderate degree of politeness as I've already managed) to a teacher. [[Special:Contributions/173.245.54.52|173.245.54.52]] 19:18, 30 October 2015 (UTC)

In your simplified version of the puzzle, Bill sees Ted has blue eyes. 
Here's Bill reasoning: 
- Either my eyes are blue or not. 
- If my eyes are not blue, then Ted knows that his eyes are blue, because the Guru said at least one of us has blue eyes, and he'll leave the island tonight. 
- Let's wait. If Ted doesn't leave tonight, that means he doesn't know his eyes are blue, and therefore my hypothesis is false. 
When Bill sees Ted doesn't leave that night, he can deduce that he has blue eyes. 
Ted can do the same reasoning. 
After that first night, both will know they both have blue eyes. 
--[[Special:Contributions/108.162.228.5|108.162.228.5]] 14:09, 14 December 2015 (UTC)

;Superrationality

The solution relies on the fact that "at least 1 blue" is new information which triggers a cascade.

Wouldn't the entire population of the island be able to conclude that everyone else on the island knows there is at least 1 blue eyed individual already?

For example, every person on the island will see at least 99 blues and 99 browns. From this, they can assume that everyone else on the island can see at least 98 blues and 98 browns. Of course, the actual numbers will differ, but 98 is the lower limit for all perspectives.

A blue will see 99 blues and 100 browns, so he will assume that all other blues can see at least 98 and all browns can see at least 99 blues. Similar logic for a brown or any observer.

[[User:Flewk|Flewk]] ([[User talk:Flewk|talk]]) 09:26, 26 December 2015 (UTC)

The solution here is different to Randall's solution, and I think is actually incorrect for two reasons that add confusion and prevented me from understanding the solution until I'd thought about Randall's solution and realised these are actually different.
* It seems to falsely presume that the Guru is speaking to them each day, when this is explicitly not the case in the puzzle.
* I also believe it is incorrect to state that the brown-eyed people can be disregarded. The solution is actually dependent on a *combination* of hypothesis testing and on theory of mind; not just one or the other. It matters that everyone is also thinking about what the brown-eyed people around them must be thinking, otherwise you can't explain why mistakes will not happen with brown-eyed people getting on the ferry when they're not supposed to, and screwing up everybody else's logic.
- If you're on the island and you have blue eyes, there are two hypotheses: either there are 99 people with blue eyes or 100. If there are 99, then everyone one of those 99 people is thinking "either there are 98 people with blue eyes, or there are 99" (and therefore you do not have blue eyes). Blue-eyed people also know that if there are 99 of them, then the brown-eyed people are thinking, "Either there are 99 blue eyed people, or 100." If there are 100, then the brown eyed people are thinking, "Either there are 100, or 101". To summarise, blue eyed people are deciding between 99 or 100, and presuming that other blue eyed people are either suspecting there could be 98/99, or 99/100, while presuming that brown-eyed people are either suspecting there are 100/101, or 99/100.
- If there are 99, then blue-eyes are thinking 98/99, and brown-eyes are thinking 99/100. Blue eyes will plan to leave if the 98th day passes and nobody has left, brown-eyes will plan to leave if the 99th day passes and nobody has left.
- If there are 100, then blue-eyes are thinking 99/100, and brown-eyes are thinking 100/101. Blue eyes will plan to leave if the 99th day passes and nobody has left, brown-eyes will plan to leave if the 100th day passes and nobody has left.
- So you know that if you have brown eyes, you'll watch all the blue-eyes leave on the 99th day. And you know that if you have blue eyes, you'll watch all the brown-eyed people hold back in case their day is the 101st. If you're allowed to leave, there will be no situation where brown-eyed people mistakenly leave on the 100th day, thus confusing things. If you're not allowed to leave, there'll be no reason for you to mistakenly make an attempt to leave on the 99th day.
- Thinking about this fact - what the brown-eyed people are thinking - also reveals why the Guru's comment matters, and adds information, even though it should seem to most people as if no information is being added (because they can all already see that blue-eyed people exist). I think this is a key part of why the problem is so tricky. [[Special:Contributions/108.162.249.155|108.162.249.155]] 07:42, 10 March 2016 (UTC)

The new information the guru gives is nothing more than a common marker (the day of the announcement) to use as a starting point for counting days. Before the announcement, being unable to communicate with each other, they were unable to coordinate a means of figuring out their own eye color.
[[Special:Contributions/172.68.59.105|172.68.59.105]] 21:52, 22 September 2016 (UTC)

That's wrong. In that case the browned eyed people would do the same, but they can't.

What I'd like to know: If there were 100 blue-eyes, 200 brown-eyes, 300 grey-eyes and 400 red-eyes, and the Guru says "I don't see anyone with a unique eye color", would that permit everyone to leave (except the Guru herself) using the same logic? Meaning the blue-eyes leave again on day 100, the brown-eyes on 200, the grey-eyes on 300, and the red-eyes on 301.

I think it would actually be days 99, 199, 299, and 300, because the 'what if there were only two blue-eyes' case would be solved on day 1 - i.e. both would see only one blue-eye and deduce that they are also a blue-eye, and both would leave - so everything gets moved up by one day.[[Special:Contributions/141.101.76.16|141.101.76.16]] 13:52, 4 January 2018 (UTC)

This was bugging me today - specifically the guru doesn't seem to actually give any information, because with at least 3 blue-eyed people, everyone on the island knows that the guru sees people with blue eyes, and also everyone knows that everyone knows the guru sees people with blue eyes. So for a while I thought the brown-eyed people must have as much information as the blue-eyed people, and either they both could leave or neither could leave.

:Consider this, if there were only 2 people with blue eyes, everyone would know that she sees someone with blue eyes beforehand, but everyone wouldn't know that everyone knows that, as the 2 people with blue eyes would not know if the other person with blue eyes can see anyone with blue eyes, so the 2 people with blue eyes would deduce they have blue eyes when the other person doesn't leave the first day, as themselves having blue eyes would be the only explanation for that person not leaving the first day. The dispute here is if you can extend that chain of reasoning past there being only two people. After all, with 3 people, as you said, everyone knows that everyone knows that she can see someone with blue eyes already, but when you consider the people who have blue eyes, everyone doesn't know that everyone knows that everyone knows that, even though each individual would personally know that everyone knows that everyone knows that, as the people with blue eyes know that if they don't have blue eyes, then the 2 people with blue eyes they see would only see one person with blue eyes and know that the Guru can see someone with blue eyes, but wouldn't know that the other person with blue eyes knows that. But would everyone follow such a chain of logic and make assumptions based one people not leaving based on days with significantly lower numbers passing that they personally know that no one would expect a possibility of anyone leaving on? This whole question is hinged on people following perfect logic that is based on other people following the same perfect logic that would predict this. If perfect logic necessitated people leaving in such a manner, then everyone would know the rest of the people would follow this rule and the solution would hold, but if it didn't, then it would be just as consistent if no one left. This is basically circular reasoning about using logic to predict the actions of people who are acting according to the same reasoning as yourself. Both this answer being correct and it wouldn't wouldn't violate pure logic based on a system of reasonable seeming logical principles and the terms of the question.--[[Special:Contributions/172.70.127.94|172.70.127.94]] 04:35, 12 October 2022 (UTC)

After a bunch of reading and testing possibilities I think I've actually figured it out now and why only blue-eyed people leave, but I haven't seen an actual good explanation for it yet, so here's my explanation: The information the guru gives is that, NO MATTER HOW MANY BLUE-EYED PEOPLE THERE ARE, they can figure out they have blue eyes. It is important that it is possible for blue-eyed people to be able to solve it for EVERY number, even if everyone knows there is more people than that number (basically because, everyone doesn't know that everyone knows there is more than that number and there's a gap in their logic without knowing that). If there is any number for which blue-eyed people cannot figure it out, then any solution (namely, what I thought before testing possibilities) would require that there is a number N of blue-eyed people that cannot leave, but a number N+1 of blue-eyed people that can leave. This is self-contradicting though. If N blue-eyed people can't figure it out, than N+1 people (regardless of eye color) can't get meaningful information from the action of those N blue-eyed people. And since they can't get meaningful information from N people's actions, N+1 people can't tell if there are N people and that individual is not blue eyed, or N+1 people and they are blue-eyed. It would be logically incorrect for them to assume an eye color at that point, which means they don't know if they can leave, and then N+2 people are similarly unable to get meaningful information from N+1 people's actions, and so on. Because a single blue-eyed person cannot figure it out, more blue-eyed people (regardless of number) cannot make any assumptions without additional information. Then the guru effectively states a single blue-eyed person could leave immediately (which means 2 could leave the next night confidently, and thus 3 the next, and so on in an UNBROKEN chain). Kejardon - [[Special:Contributions/162.158.214.82|162.158.214.82]] 11:15, 9 January 2020 (UTC) (I doublechecked and edited/corrected my post kind of at the same time, so your reply doesn't make sense anymore, sorry Lupo. Feel free to delete these two sentences if you change/delete your reply)
:You bring up 2 points. First about the common marker. This is true, but it contains more information than "start counting from today," because every blueeyed person has 2 scenarios: With 99 blue eyed people and with 100. The numbers are not important, and it would also be needed with 1,2,3,etc. blue eyed people. The point about the brown eyed people: The brown eyed people have no way to conclude (remember, they are "perfect logicans" and their task is to figure out, not to make an estimated guess) that their own eyes are in fact brown, and not red, or green just like the Gurus. If the guru just said: "Start counting", then noone woul leave at any given night. --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 11:05, 9 January 2020 (UTC)

I figured this out in less than a minute... there were so many warnings about the solution being convoluted that I thought I couldn't possibly have it right. It's not really that confusing and I've seen waaaaaaay harder logic problems.

This image is listed under "My Hobby" for some reason, despite not even being a comic, let alone a "My Hobby" comic. [[Special:Contributions/162.158.111.151|162.158.111.151]] 00:58, 9 September 2019 (UTC)How sign edit

It's been years and I stumbled back across this post, and I think I finally understand what has been bothering me.
The examples always go up to 3 blue-eyed people, and then we just assume that it follows a the pattern, but a pattern has to be confirmed to all states to be a proof. This is why Fermat's last theorem remained unproven for years even though we had solved the N =1,2,3 cases. To expand on the biggest criticism, what new information does the guru give? 
-Someone learns something : Only true from the perspective of someone who sees no-one with blue eyes. 
-Someone could learn something : Only true from the perspective of someone who sees exactly one person with blue eyes. 
-No-One can learn anything : True from the perspective from someone who sees multiple people with blue eyes. 
This is where the problem occurs, because this only resolves with 3 blue-eyed people otherwise we don't learn anything, but how we acknowledge that we don't learn anything matters. 
-Everybody must know that no-one can learn : True from the perspective of people who see people who must see multiple people with blue eyes. 
-Everyone must be aware of the previous fact : I guess it does go on... 
In the end, it's all about the meta-data. 
I know, you know, they just don't have any proof... 
Crow --[[Special:Contributions/108.162.245.65|108.162.245.65]] 00:12, 30 September 2021 (UTC)

Apostle's Solution: The first person to look into the water and see their own reflection. For a logic puzzle, people seem to forget about the situations actual logic. {{unsigned ip|162.158.74.213}}
:What part of: "There are no mirrors or reflecting surfaces" do you not understand? --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 09:54, 18 May 2020 (UTC)
:What can you even do to an island to remove all reflecting surfaces? Absolutely everybody would leave the the night after the weather is good enough to see their reflection in the sea.
::Then the weather is never clear enough to see their reflections. It's equally valid to question why the ferryman would only free people who knew their eye color, or whether some people would want to stay on the island instead of leaving...and far ''more'' valid to point out that perfectly logical beings like the problem describes ''don't exist''. If you're not willing to suspend your disbelief enough to accept the premise of a logic puzzle, that's fine, but it's no more ridiculous than suspending your disbelief enough to accept that hobbits and wizards exist in Middle Earth. [[User:GreatWyrmGold|GreatWyrmGold]] ([[User talk:GreatWyrmGold|talk]]) 03:29, 17 July 2021 (UTC)

If there are N islanders with blue eyes, every person sees at least N-1 blue eyed persons. Person A with blue eyes seeing N-1 blue eyed persons has to consider the possibility that there might be a person B who only sees N-2 blue eyed people and acts accordingly. However, everyone in that scenario will agree that it is absolutely impossible for anyone to see N-3 or less blue eyed people and that case cannot possibly be considered by anyone. Therefore the induction step is invalid and nobody will ever leave the island for N>3. [[User:Boopers|Boopers]] ([[User talk:Boopers|talk]]) 18:07, 15 October 2021 (UTC)

If a person B only sees N-2 blue eyed people, then surely they have to consider the possibility of a person C who only sees N-3 people. Sure, person B doesn't actually exist in this scenario, but you'd have to consider that person A would have to consider what a hypothetical person B would have to consider. It's turtles all the way down. [[Special:Contributions/172.70.110.171|172.70.110.171]] 00:17, 19 October 2021 (UTC)

No. It doesn't turtle down and nobody inside the scenario is free to consider any hypothetical persons. Instead, everything that one of the persons may consider about another person on the island has to be consistent with his observations of the persons who are actually there. And that breaks down at person C in my example. Yes, person B from the example does not exist, but the important thing that was being missed is that person C can be proven by everyone involved to be impossible which is not the case for B.
Lets just consider the scenario with 4 blue eyed persons, the smallest number where the argument breaks down. Now lets choose two completely arbitrary persons A and B (And I really mean completely arbitrary - doesn't even require for A and B to be different persons). It can be shown that A knows that B sees at least 2 blue eyed persons. Now since A and B were chosen arbitrarily, that means that every person on the island knows that every person on the island sees at least 2 blue eyed persons. This observation is of great importance, because it contradicts an invalid assumption implicitly made in the induction step. The induction step relies on the incorrect assumption that at the end of day N knowledge is gained that the number of blue eyed persons is larger than N. That assumption works out well for 2 or 3 blue eyed persons, but completely breaks down at 4 blue eyed persons right at day 1, since we have shown that everyone is already aware that there is more than 1 blue eyed person before the end of day 1.
This invalid assumption is extremely well hidden in the presented proofs. In the "Intuitive Proof" section, it is hidden inside the wrong assertion that the simplified problem supposedly is equivalent to the original one when it is absolutely not. And in the "Formal Proof" section, the islanders are just being assigned a reasoning without there being a proof to why they would reason this way. Of course following this flawed reasoning will lead to the desired result, but if they were the perfectly logical thinking people like the problem described, they wouldn't just miss the fact that there are cases where no knowledge can be gained on day 1 and therefore on any of the following days, and they would incorporate that into their reasoning. [[User:Boopers|Boopers]] ([[User talk:Boopers|talk]]) 18:31, 13 November 2021 (UTC)

Boopers, let me see if I can convince you it works for n=4 by making it a story. There are 4 blue-eyed people on the island; Arnold, Boopers (you), Carl, and Denise. You don't know your eye color, but have always thought of yourself as a brown-eyed person, and if you had to guess, you would guess you have brown eyes; after all, almost everyone does. When you hear the guru speak, you think that since there are only 3 blue-eyed people, A, C, and D. They are dear friends of yours, and you are very sad that after 3 days, you will never see them again. So you have a busy 3 days coming up, since there are things you've put off doing that you must do quickly, before A, C, and D leave your life forever.

A, while a good friend, has a habit of borrowing things and not returning them, and you don't want your stuff going with A on the boat. So you spend day 1 getting A to return your lawnmower, snowblower, and the dozen books he has borrowed over the years and not returned. You get all your stuff back. A good day 1.

While C is a friend, you haven't always treated him well. So day 2 you spend with C, doing whatever you can to ensure he has a good day on his next-to-last day on the island, and apologize to him for the ways you have wronged him in the past. He accepts your apology, and you are pleased that you haven't left things unresolved with your friend who will leave the island forever in 2 days. A great day 2.

On day 3; you confess to Denise (who is married to Arnold) your undying love for her. You've never told her this, out of respect for her marriage, but you've always suspected that your feelings were returned. Now that you will never see Denise or her husband again after noon tomorrow, so there will be no repercussions. To your delight, you discover that your feelings are indeed returned, and you and Denise spend what you think will be your last night together making love until the early morning hours. A perfect day 3. And since A and D are leaving on the boat the next day, and you, with your brown eyes, are staying on the island, probably forever, there will be no repercussions.

The next day, when you know A, C, and D will be leaving at noon, you rise early, and just before noon, you head to the pier, wanting to see Denise once more before she leaves on the noon boat. A, C, and D are of course there too. But to your great surprise, when the "all aboard" is sounding, A, C, and D do not move to get on the boat.

How can this be? What has happened? Again and again you go over the logic that says "if there are only 3 blue-eyed people on the island, they will all leave on day 3" and find it to be ironclad. And you know that your friends A, C, and D are perfect logicians, and can reason the same way you do, and you certainly know that they would never violate the rule that if you know your eye color, you must leave. And yet they remain! It seems impossible! How can this be? Unless...

Does a possibility occur to you to explain their inexplicably remaining on the island? You are certain of your logic that says "*If* there are exactly 3 blue-eyed people on the island, they will leave on day 3". So it must be that there are more than 3 blue-eyed people on the island. But you re-check the eye color of everyone else you can see, and they are all brown. Do you realize what must have happened?

Do you now know your eyes are blue? Do you get on the boat on day 4? [[User:Yp17|Yp17]] ([[User talk:Yp17|talk]]) 19:14, 9 February 2022 (UTC)

I think that helps highlight why the induction as presented doesn't work. Indeed, I believe everyone leaves on the 4th night, and that the Guru provides no information at all -- only a random token which could not have existed before since communication was impossible.

Once the Guru speaks, the solution becomes possible for only the case of blue-eyed people, because only then can every person on the island be sure they are counting the same color. But the content of what she says is meaningless, as everyone already knows what she says. She could have simply said, "Blue eyes", and the same result could be accomplished (I in fact nominate that for a harder form of the puzzle).

Following this, the expected reasoning happens, but there is no reason for it to stop at the time presented. Waiting one day to see if there is one blue-eyed person that will leave is meaningless and completely irrational -- every person on the island can see enough blue-eyed people to know, with certainty, that every person knows there is more than one blue-eyed person. Therefore, waiting that first night is wasted, since the outcome is known with absolute certainty. Waiting must logically begin only on the first day where the outcome is not certain.

To find that day, the relevant metric is the lowest number of blue-eyed people that can be known to exist to every person on the island. That number is 97 -- consider a person A, blue-eyed, calculating the knowledge of another person B, also blue-eyed. (If either are brown-eyed they can mutually estimate more blue-eyed people, so this is the relevant case.) Since A is uncertain of their eye color, they must for the worst case assume it to be brown; therefore, they estimate 99 blue-eyed people, of which B is one, whom therefore sees 98 blue-eyed people in this scenario. B cannot be sure of their own eye color, so they will see 98 blue-eyed people, and when modelling a further person (C, say) following the same logic could conclude they themselves are not blue-eyed and therefore C will only be able to guarantee 97 blue-eyed people (A's model is, A is brown, and B's model is B is brown, so C's model excludes A and B and is uncertain about C.)

Importantly, this does not induct! There is no rational way in the given 100/100/1 distribution for someone to not be certain of 97 people, even though there is a temptation to chase a clear recursive pattern. The reasoning behind it does not hold -- A does not need to worry about B->C->D's model, because no one has that much uncertainty -- it is incorrect to model D, because you can observe everyone's computation at most two steps removed from directly. When establishing a pairwise estimate of the distribution of eye colors, there are only two points of uncertainty -- the observer, and the person being modelled. A knows, with certainty, that there is no situation where someone will model the behavior of another and find a lower bound of less than 97, because even if A is brown-eyed, they know every other person on the island will see at least 98 blue-eyed people, regardless of all other factors.

The salient modelling question is, therefore, only how much "worse" than 98 it can be. One may be tempted to assign another -1 to the new observer who then must assign another -1 to their target, but that is illusory -- in our previous example, the uncertainty with which C considers D is the same uncertainty that A already accounted for, i.e. the uncertainty of the observer. No matter who is modelling who, there is only one observer, one modeled-observer, and one modeled-observer-target. Further extrapolation isn't necessary. Therefore, since A knows they are looking at someone with blue eyes, that person B can conclude that of the 98 people they assuredly see, they must subtract only one more for the worst case -- the estimate of C, who knows not their own eye color. B doesn't need to account for their own eye color, because A already did that in their own uncertainty, and they know that B is blue-eyed -- no matter who they select of the 99 blue eyed people they see, that person will see (at least) 98 blue eyed people, and gives no greater uncertainty than the case where A is brown eyed and they are considering someone else blue-eyed, lowering the bound to 97. It in no circumstances is estimated lower than this.

That means that every knows, with certainty, there are 97 blue eyed people at a minimum, and therefore the first interesting day is the 97th on the "original timeline" -- but that clearly isn't the case, because everyone can already count more than 97 blue-eyed people. Indeed, everyone can count 99 blue-eyed people; it is only in question for each observer whether they are a 100th blue-eyed person, and the chain of reasoning exists to expose that. The worst-case 97 holds only if his own eyes are brown, and another blue-eyed person considers a third blue-eyed person. Since there is no way to communicate, there is no way to improve upon that uncertainty, so that must be the point of first decision:

The first interesting night requiring a decision is establishing whether 97 people have blue eyes, or more than 97 people. This could be known with ceratinty by the original reasoning, which persists until the 97th night. However, everyone knows, with certainty (due to the above) that every night prior to the 97th night will result in no action; therefore the only logical course of action is to begin with the first point of new information. They "start" with the 97th day, and leave on the 100th, for a total of 4 days. [[User:Dokushin|Dokushin]] ([[User talk:Dokushin|talk]]) 07:55, 26 February 2023 (UTC)

:You are 99% of the way there... to explaining why the solution does not work at all. You are absolutely correct that there is no reason for anyone to assume that anyone else would ever assume less than 97 blue-eyed people, and therefore the induction does not carry through. But this means they have absolutely no grounds whatsoever to start making any assumptions about who could possibly figure anything more out and therefore who & when could possibly be getting onto the boat. In the presented scenario, no one ever leaves. It could only be different if the guru spoke about seeing 98 blue-eyed persons. [[Special:Contributions/172.70.85.125|172.70.85.125]] 11:11, 30 September 2023 (UTC)

;Unstated assumption (about motives)
While trying to solve this, I started questioning my assumptions about the motives of the islanders. It turns out my assumptions were correct, but I think they deserve to be explicitly stated:
# Everyone wants to leave the island ASAP.
# An islander only "figures out" their eye color through logical deduction (no guessing or playing the odds)
# The Guru's statement is meant to help others leave the island. (but as stated above, it may not be the optimal means of helping others leave -- "nobody has a unique eye color")
:Regarding the 1st point: Yes, that needs to be stated.--[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 11:37, 9 January 2020 (UTC)
:Regarding the 2nd point: It should be mentioned, but could be implied by the words "figure out" and by the fact that everyone is a "Perfect logican". --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 11:37, 9 January 2020 (UTC)
:Regarding the 3rd point: If it was not meant to help people leave, it would still do the same job. Also the statement from the Guru "nobody has a unique eye color" would be wrong and misleading! In that case everyone would wrongly assume: "I must have green eyes, as otherwise the Guru would have an unique eye color." - The alternative statement "I see noone with a unique eye color" would work. --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 11:37, 9 January 2020 (UTC)

Storming lighteyes (not sorry) [[User:SilverMagpie|SilverMagpie]] ([[User talk:SilverMagpie|talk]]) 17:50, 10 January 2020 (UTC)

;Guru gives synchronizing signal to begin recursive cascade, without which it can’t start.
We might wonder why it is noted that the islanders have been on the island “all these endless years”, but the recursive cascade had never happened. The reason is that There must be a time zero, T0, from which the wait period is defined. Without that discrete starting point, there is no reference point to begin waiting to see who leaves. The Guru provides a starting event, visible (or audible) to all, where they can say “this is T0”, and our deductions can now proceed. So it synchronizes everyone to begin their waits.

I finally got this one, and while this may be repeating others' explanation of "what info does the Guru provide", I'll try another way in the simple way that was MY "aha!"/satori moment in hopes it'll help someone else too:
(A) as others have pointed out, the case of 100 reduces down to 1 (if there were 1 blue-eye, that statement would do it in 1 day, so it cascades for cases of 2, 3 etc.);
(B) once the Guru "triggers" that cascade, you just count the other people with blue eyes, and wait that number of nights; when it hits zero, leave. (It works for 1 (leave that night), for 2, (leave next night), 3 (leave the 2nd night)....)
(C) SO: the Guru saying it the statement is basically "I am hereby "triggering the "Blue-Eye Cascade". It's NOT so much whether ANYONE CAN SEE A BLUE-EYED PERSON - obviously everyone on the island can!

* '''It's the Guru BEING A LOGICIAN, AND TRIGGERING A LOGICAL CASCADE FOR THEM. S/he could've ALSO said BROWN - and THAT would've had the OTHER effect - because that'd have been giving THAT "hint"/"clue" (!!!!!!!)'''
[[User:Abner Doon|Abner Doon]] ([[User talk:Abner Doon|talk]]) 16:12, 16 April 2023 (UTC)

what if there is 1 blue-eyed person on the island outside of houses while the guru is saying that, and everyone else is in houses with their windows and doors shut? [[User:Plushiefan4111|plushie fan]] ([[User talk:Plushiefan4111|talk]]) 15:47, 22 November 2023 (UTC)

^^^ Trying to "break" the problem in this way leads to no greater understanding of the stated logic problem or its possible solution(s). --[[Special:Contributions/162.158.167.19|162.158.167.19]] 00:43, 10 December 2023 (UTC)

You could point at water or dirt then point at your eyes and tilt your head questioningly as if to say "Which one? Brown or Blue?"
Simple. [[User:Psychoticpotato|Psychoticpotato]] ([[User talk:Psychoticpotato|talk]]) 21:44, 4 April 2024 (UTC)
:"No, you don't ''look'' like you're crying..." [[Special:Contributions/172.70.162.19|172.70.162.19]] 23:28, 4 April 2024 (UTC)

Isn't the problem a little more complex, because the way Randall phrased it, Anyone who *knows* their eye color can leave. regardless of whether the eye color is brown or blue {{unsigned ip|108.162.238.76|22:10, 11 June 2024}}
:The information of there being "(at least) one person with <colour> eyes" eventually triggers every person who can see 99 pairs of eyes of <colour> and 100 pairs of eyes of <unstated colour> to leave on day 100, in a way that a person of <unstated colour> eyes cannot be. Nor even, with the benefit of another day but no further information (not even the fact of the departures), could they know that they are not personally <yet another colour>ed (e.g. another green-eyed person, like the guru...).
:Until the declaration of there being a blue-eyed person present, there's no base from which the blue-eyed can (eventually) logically deduce they should leave. It would take a similar declaration about brown-eyedness to (eventually) lead to all browns leaving, but that's not stated.
:As far as I can work out, there's no statement(s) that the Guru could make which would lead to the Guru leaving, without a defined subset of possible eye colours to rule out. They could accept that the logically-derived departures of all blue-eyed ''and'' brown-eyed residents meant that they were in neither the brown nor the blue cohorts, themself, but that only helps if green is known to be the ''sole possible'' third option. Four or more (or undefinedly many) leaves them still uncertain. [[Special:Contributions/172.69.195.63|172.69.195.63]] 09:02, 12 June 2024 (UTC)
:Shorter version: seeing 100 blue-eyed people and 99 brown-eyed ones (and 1 green-eyed one), you can ''expect'' to see the blue eyes leave on the 100th day. But that doesn't help identify your own eyes. (If the 100 do ''not'' leave, you would have learnt that you are the 101st blue-eyed person, someone that each of the other hundred blues observes as their own potential 'other hundred', and will join the departure the day after after establishing that you are one of the 101.) But every person can imagine having ''any'' type of eye, if the logical proof of being blue does not end up resolving to apply to them. [[Special:Contributions/172.69.195.184|172.69.195.184]] 12:38, 12 June 2024 (UTC)

I think that the invalid nature of the solution lies in the assumption that all islanders will adopt the same strategy to determine the number of blue-eyed islanders. It may appear that this is addressed in the premise of all islanders being perfect logicians, but this is not the case when there are numerous equally logical strategies. {{unsigned|Ningnong|22:38, 3 September 2024}}
:That there are numerous equally logical strategies (which ones were you thinking of?) needn't be a logistical problem if all logistically perfect islanders are aware of each of them and then enact the ''first'' strategy that provides its solution. (i.e. if there was some other reason to act, prior to the stated time to do so, it wouldn't matter that there was still the comic's logistical 'answer'; the prior conclusiveness would have been obeyed already...)
:In order to have a conflict, you'd need a rival logic that would apply in a different order to different people. The only real difference between people is which eye colour they have (you see 100 pairs of eyes of the other (non-guru) colour from you, 99 of your own – though of course you don't know this until the logic tells you that this must be the case) but that's already the threshold value that kicks in the 'perfect logic' reaction from those that need to (if it had not kicked in, then you'd have waited another day to resolve the next possible hypothesis). With some reason to have acted the day ''before'', everybody in your position would have acted the day before.
:There cannot be two (valid) logics that suggest different conclusions to different people, as given. The closest you can get is instead having a 101:100 split (or other similar issue of uneven non-guru numbers), in which everybody who could be "the 101st" is seeing 100+100 and could consider being 101st of ''either'' colour. (Prior to that, someone who sees 101+99 can wonder if they are "the 100th", but the alternative is go be "the 102nd" of the alternative, whose 'proof day' has yet to come). But the balanced numbers, ironically, ensures an imbalance in the potential 'proof-days' that means that two different interpretations cannot become 'true' on the same day. [[Special:Contributions/172.70.91.58|172.70.91.58]] 01:17, 4 September 2024 (UTC)
::For example, they could proceed as if the Guru said it two days ago. Or a week ago. Or 90 days ago. The 'solution' hinges on the assumption that they all start their deductive process at the same point. In fact, if they picked a different strategy (still requiring a hive mind) they could actually figure it out much more quickly. [[User:Ningnong|Ningnong]] ([[User talk:Ningnong|talk]]) 22:20, 4 September 2024 (UTC)

"If P then Q" is true is P is false.

Theorem 1: If exactly one person has blue eyes, no one will ever leave the island. It is not the case that exactly one person has blue eyes, so this theorem is true.

Alternatively,

Theorem 1: If exactly 97 people have blue eyes, they will leave the island as soon as the guru makes his statement. Everyone knows that not exactly 97 people have blue eyes, so this theorem is also true, so 96 or so days can be cut from the original inductive proof. {{unsigned ip|172.68.3.7411:30, 1 October 2024}}
:No, lost me there. Looking at the second, if there are 97 people on the islend with blue eyes (assume 103 with brown eyes, plus green-guru), then all blue-eyed can see 96 blues (could be 97, if they are one) and 103 brown eyes (could be 104, if they are one) and 1 green eye (could be 2, if they are one). And no other colours (though they could ''be'' the one!). But I'm not sure how that helps shortcut.
:Some people will see numbers of eyes in others and know that ''at least'' so many days need to be 'wasted' before it becomes clear whether one must assume that one is the extra person with blue eyes. This raises the possibility that the perfectly logical inhabitants can skip over the 'waste days', perhaps. But if you're a blue-eye you'd know you'd need to waste a number of days that is less than must be known to be wasted by a non-blue-eye, and you don't actually know whether you're in either camp, so is it possible that everyone can make the assessment of how many days everyone else thinks should not bother to waste, and get straight to the post-waste (or maybe within a day or two of it, depending upon your personal ideas)? Well, not really, because blue-eyed and non-blue-eyed would have different "If I am not, then we can skip N, if I am, then we could skip N-1" values. Without communicating what value of N each person considers (breaking the rules, and would immediately reveal if you are the same/different from the comminicator), there seems to be no logical amount of 'assumed days to not bother wasting' to shortcut everyone to jump straight to (or nearly straight to) whether the exodus happens.
:As to the first form, If exactly one person has blue eyes, they get told there is someone with blue eyes, they can't see anyone with blue eyes, therefore they know their eyes are blue, therefore they leave.
:I also can't really parse <code>"If P then Q" is true is P is false.</code> in the first place. As I read it, given a test/result of "If P then Q", and the result of that is true (by which you mean, Q is true), then P must be true and then... well, not sure where you go with the rest. But that's already potentially wrong, because Q could be true without P (unless you specify "Iff P then Q"). But perhaps you need to explain that more. [[Special:Contributions/172.69.79.138|172.69.79.138]] 12:42, 1 October 2024 (UTC)
::The statement "If P then Q" is commonly discussed when discussing logic. If P is true, then Q must be true for the entire statement to be true. If P is false, it does not matter if Q is true or false (e.g. "if 2+2=5, then the sky is green" is a true statement because the first part is false). Applying this to the Blue Eyes problem, the theorem "If exactly one person has blue eyes, then no one will ever leave the island" is true because it is not the case that exactly one person has blue eyes. All the theorems that start with "if there are exactly N blue-eyed people on the island" with N < 98 are true because everyone knows there are at least 98 people with blue eyes. It does not matter what the second part of the theorem is. With all those nonsense theorems, the induction falls apart.
::That said, I am not as smart as Randall so I am very likely missing something. Perhaps a different wording of the theorems would clear things up for me. But as the solution is stated, you could jump right to Theorem 97 and replace the 97th night with the first or 1000th or -9999th and the Theorem would still be true.
::I made a typo earlier. "If P then Q" is true '''if''' P is false. There are lots of explanations out there that are better than mine.([[Special:Contributions/172.68.1.158|172.68.1.158]] 00:52, 2 October 2024 (UTC))
:::The if/is typo did not help. Also arguable whether "This statement is false" can be true if you later specify that the statement is not an applicable statement.
:::Everyone knows there are at least 98 people, but everyone does not know that "everyone knows there are at least 98 people".
:::#Everyone (blue) knows that there are at least 99 people, to contrast with everyone (not-blue) who knows that there are at least 100 people.
:::#Everyone (blue) can imagine that the 99 blues they see are thinking the same as them (if they are blue), or thinking that it's 98 blues (if they aren't).
:::#Everyone (not-blue) can imagine that the 100 blues they see are thinking "at least 99", in the one case (of unknowable self-realisation) or "at least 100" in the other.
:::#*In first-order analysis, everyone can imagine there are anywhere from 99 to 101 blue-eyed people... 99: blue-eyed does not imagine they are; 100: blue imagines they are blue, ''or'' not-blue imagines they are not-blue; 101: not-blue imagines they are blue
:::#Infering the thoughts of the (99 or 100) people of either eye-colour must apply the unknown quality of the inferer's eyes to the way that the inferee's own inferences must be shaped.
:::#*This 'second-order' analysis gives the 'infered inferences' a range of 98 to 102: a blue imagining they are not blue would anticipate another blue (imagining they are not) establishing a theoretical 98 'true-blues' (not the original inferer, nor the inferer's theoretical inferer). A non-blue who imagines wrongly could imagine another non-blue imagining wrong (their +1 misassessment added to the other's +1) to give an upper-limit of 102.
:::#*But note that the 98 'lower limit' (at two orders of logical carry-through) is only applicable to blues (who do not yet know they are blues, and know that all other blues do not yet think they are blues). Non-blues have 2nd-order 'lower limit' that is greater than 98 (i.e. 99: Non-blue imagining correctly, imagining a non-blue imagining wrongly)
:::#Beyond this, it calls into question the original truth or falsity of the assumptions made by the 'master inferer' in their recursive inferences, since the 'truth' of their own eyes becomes again part of the bounding logic-chain of "they might be imagining one less (or more!) such person than I am imagining".
:::#Everybody can probably agree (wordlessly) that there are more than N blue-eyeds, such that N steps ''could'' be skipped to get straight to the point of every blue-eyed person that can be seen (by a non-blue) leaving at the first opportunity. But how to agree upon that N, when some Ns are N+1?
:::Worse than that, the step in the solution to prompt someone to leave is that they observed that all those others who should leave did not, bringing the realisation that they should (anyone who actually should not leave, in the possibility that they theoretically must eventually, would have been prompted to the day ''after'' everyone a tually left, but only if they actually had not). If everybody has their own idea of N and N+1, and they wait to see if the Ns leave, then nobody leaves for 'their' N and then the next day ''everybody'' assumes their N+1 applies and leaves.
:::If only everybody knew what N everybody else was thinking about..? But they aren't allowed to communicate. Except in just the ''one'' way: By leaving (or not) each day. All non-departing days, from the guru's initiating statement onwards, is a logically agreeable increment of the value that eventually becomes (the correct) N.
:::When the day count gets high enough that theoretically everybody that a person sees as blue ''should'' have left, this prompts the blueness-realisation in that person (and all fellow blues, who had themselves down as the unknown quantity instead) and creates a departure event upon the next day. (And thus forestalls all non-blues from erroneously thinking themselves "the last self-unknowing blue" and trying to depart the day after.)
:::Simple? [[Special:Contributions/172.70.160.230|172.70.160.230]] 08:30, 2 October 2024 (UTC)

Why can't the guru just say "I see 100 blue eyed people and 100 brown eyed people" on day one?[[Special:Contributions/104.23.190.137|104.23.190.137]] 14:56, 6 March 2025 (UTC)
:Then there wouldn't be a puzzle. (Or, if you prefer, "only the guru knows, probably hence why they're the guru".) You might as well ask why there's the rules on what people must and must not do (not openly speak/sign-language to others about their own status, and leave immediately upon having the required knowledge, plus ''never'' try to look into any decent reflective surface). Given the setting (presume some sort of island of myth), probably there's some sort of enchantment/geas/divine-command laid down upon the community, whether intended to be so restrictive (yet have the logical loophole that allows the guru their single utterance of no ''immediate'' value) or an unfortunate mistake by whatever power it was that blanketed them all within this scenario. [[Special:Contributions/172.70.162.57|172.70.162.57]] 16:08, 6 March 2025 (UTC)

1031: s/keyboard/leopard/

2025-08-17T19:33:44Z

Giraffequeries: I just deleted the weird vague part entirely. I don't know what the heck that user was doing.

{{comic
| number = 1031
| date = March 19, 2012
| title = s/keyboard/leopard/
| image = s keyboard leopard.png
| titletext = Problem Exists Between Leopard And Chair
}}
Clicking on the image takes you to [http://wiki.xkcd.com/irc/Leopard this link] (now defunct, [https://web.archive.org/web/20190810230906/http://wiki.xkcd.com:80/irc/Leopard archive]).

==Explanation==
{{notice|[[#Trivia|''jump to incomplete part)'']]}}Extensions are small programs that install into your {{w|Internet browser}} and change the Web pages as you view them. Some make pages easier to read, some remove ads (the third extension is [https://chrome.google.com/webstore/detail/adblock/gighmmpiobklfepjocnamgkkbiglidom AdBlock]) and so on. [[Randall]]'s browser looks like {{w|Google Chrome}} as viewed on a {{w|Mac (computer)|Mac}}, and he has installed at least four extensions on it, which explains the little symbols to the right of the address bar.

For the joke in this comic, an extension accidentally replaces the word "{{w|Computer keyboard|keyboard}}" with "{{w|leopard}}" in a regex (or {{w|regular expression}}). In computing, a regular expression provides a concise and flexible means to "match" (specify and recognize) patterns in text, such as particular characters or words. The command to substitute/replace a string is "s", e.g. "s/old/new/g" replaces any occurrence of "old" with "new". The title therefore contains the command to change "keyboard" into "leopard".

It's not clear what the extension Randall installed was actually supposed to do, but most extensions that revolve around text replacement are humorous in nature (such as [https://chrome.google.com/webstore/detail/cloud-to-butt-plus/apmlngnhgbnjpajelfkmabhkfapgnoai?hl=en Cloud to Butt], which replaces all instances of "[[908: The Cloud|the cloud]]" with "my butt").

The title text references the common IT phrase "Problem Exists Between Keyboard And Chair" or {{w|PEBKAC}}, which means that the problem is caused by the user, not by any failure of the computer. However, due to the substitution, it is now "Problem Exists Between Leopard And Chair". It could also be a reference to [[A-Minus-Minus]], the comic containing the phrase "Instead of office chair, package contained [[:Category:Bobcats|bobcat]]".

There has been several [[:Category:Substitutions|comics using substitutions]], both before and after this one.

===Sentences===
; Weird, my leopard just switched to Chinese.
: Sometimes, the keyboard settings may switch to Chinese due to a bug, or by unconsciously making the change. It is quite common for users with non-US keyboard layouts to find they have accidentally switched to the 'default', and conceivably this 'feature' could work the other way. Especially on systems with significant historic Chinese involvement in its [[2166: Stack|development]].
: Leopards are not known to speak at all, let alone Chinese. Alternately, it refers to a change in diet of {{w|Man-eater|one form}} or {{w|Chinese restaurant|another}}.

; I work with one leopard on my desk and another in the leopard tray.
: Keyboards often take up desk space, and one solution is to have a [https://www.bpfonline.co.uk/search.asp?catid=2737 keyboard tray] that slides from under the desk, or out of the computer cabinet, when needed. This person apparently has two ''separate'' keyboards attached to their system(s), one taking up desk space and the other on the tray. This is probably more convenient than having two keyboards side by side (or on top of each other) on the desktop or two separate 'trays' (or two keyboards somehow jammed into the same tray), and often a person with such a requirement will have a computer for typical use (with the most accessible keyboard) and a second one only occasional use (with the second keyboard). They could also use a {{w|KVM switch}} for some of the peripherals, but it may not be quite as convenient or as easy to set up as to double up on the keyboards.
: Leopards are traditionally solitary animals outside of mating season, or when a mother is raising her cub(s), and so however practical it is to have two leopards in close proximity, it might be a somewhat necessary compromise to give them each their own area in a given workspace. However, it is generally uncommon to put a leopard in a ''tray'' specifically.{{Citation needed}}

; Ever cleaned a leopard? They're filthy.
: Most people will use a keyboard for a long time, rarely replacing them unless they are actually broken, and possibly using old ones with new computers (if not integrated within their system, as with laptops). All this time, general detritus, skin, hair and even scraps of food will accumulate upon and beneath the keys unless cleaned thoroughly. Most people don't try to clean a keyboard ''until'' the accumulated grime starts to make typing a problem with less sensitive (or over sensitive!) keys. If you're finding it necessary to clean a keyboard at all, you will probably find quite a lot of filth to clean off/out.
: Leopards, like most cats, are generally adept at keeping themselves clean. However, as a wild animal they're perhaps considered less 'clean' than one would hope a household or workplace appliance might be, and this would depend upon one's attitude to their grooming by licking themselves all over.

; The iPhone virtual leopard is the fastest IMO.
: The response time of a keyboard is one of the factors that determine its quality, and the ability to rapidly enter characters (words, code, commands). A {{w|virtual keyboard}}, often implemented as a touch-screen 'app', has to integrate into the interface and the speaker here apparently rates the default iPhone type more than others of this kind.
: Real leopards are known to run fast. It is possible that a virtual leopard may be made to exemplify this speed. The makers of the iPhone have possibly made a virtual leopard that is faster than all real leopards, or at least they have made ''their'' virtual leopard faster than all other virtual leopards from all other vendors.

; I rarely email from my phone—I'm so slow when I'm not on a leopard.
: A disadvantage with virtual keyboards is often the lack of {{w|Haptic technology|haptic feedback}}, as well as the compressed and compromised layout required to fit the keys within interface. It is often much easier to use a proper full-sized keyboard, whether you hunt-and-peck or are an accomplished touch-typist, although this may depend a lot on practice.
: In the context of leopards, the individual concerned seems to appreciate the advantages of being on an actual leopard when emailing, as it makes them faster. This could mean faster because the leopard itself is wont to run around. Or perhaps it is because sitting on the back of a leopard (not particularly known for being a patient beast of burden) means you ''have'' to do what you are trying to do much faster, before the consequences being on a (possibly annoyed) leopard literally come back to bite you.

; My leopard died when I spilled tea on it :(
: Keyboards are not generally waterproof, and react badly to any liquid spill upon them. If you are lucky, you can quickly drain them, let them dry and they will not suffer too many ill effects in the long run. But, if the less resiliant electronics get directly affected, it can mean having to replace the now unresponsive keyboard.
: Leopards are animals which eventually die. They are not known to be particularly susceptible to tea, as a substance, although the typically very hot water would not be comfortable and might contribute to the mortality of one in certain circumstances. Either way, it seems like an upsetting experience. "My leopard" suggests (as with several of the above) that a leopard is being kept as a pet, working animal or perhaps a personal zoo inhabitant, and the loss certainly seems more than if a random leopard were accidentally splashed with a drink.

==Transcript==
:[There are two browser windows open on a computer screen.]
:[The first browser window, taking up most of the screen, but partly blocked by the other window at the bottom, has a Wikipedia article open. The title of the page can be seen on the active tab.]
:Computer leopard - Wikip...
:[Next to the address bar are four add-ons and the toolbar icon. One of the add-ons is a letter:]
:R
:[To the left on the page are standard menus, with lots of unreadable text, except these words:]
:Help
:Go Search
:[The page is not at the top of the article, so the text begins mid sentence, the very top of the letters just cut of in the first visible sentence.]
:which range from pocket-sized leopards to large desktop leopards, the leopard remains the most common user input device. In addition to text entry, specialized leopards are used for computer gaming.
:While many computer interfaces rely on mice or touchscreens, UNIX-style command-line interfaces require users to interact with a leopard.
:[Below is the contents list - the text in the brackets can barely be read. And only the very top of the 2.3 line can be seen, and is thus only a qualified guess at what it was supposed to say, although it fits with the real wiki article.]
:Contents [hide]
:1. History
:2. Leopard types
::2.1 Standard
::2.2 Laptop-sized
::2.3 Thumb-sized
:[To the right there is a picture of a keyboard. The picture text written below:]
:IBM Model M Leopard

:[The second browser window overlapping the first, at the level of the 2.3 menu point in the content menu, is a message board. The title of the page can be seen on the active tab:]
:Discuss - Leopard issu...
:[Next to the address bar are four add-ons and the toolbar icon. One of the add-ons is a letter:]
:R
:[In the window there is a list of topics next to icons of those starting the topic. The top post is just inside the frame, the icon cut of at the very top.]
:[Face of Cueball-like guy on white background:]
:Weird, my leopard just switched to Chinese.
::3 days ago
:[Super close-up of the head of a person with dark hair on black background:]
:I work with one leopard on my desk and another in the leopard tray.
::3 days ago
:[Full picture of a Cueball-like guy, with white background in the bottom half and dark in the upper half (which would conceal any hair on the persons head):]
:Ever cleaned a leopard? They're ''filthy''.
::2 days ago
:[Head of a cat on black background:]
:The iPhone virtual leopard is the fastest IMO.
::19 hours ago
:[Head of a girl with long blond hair on white background:]
:I rarely email from my phone—I'm so slow when I'm not on a leopard.
::11 hours ago
:[Head of Cueball-like guy. A line seems to be going our from his head, but it could just be one of the lines used to fill in the background:]
:My leopard died when I spilled tea on it :(
::2 hours ago

:[Below the main panel of the comic is the following caption:]
:The Internet got 100 times better when, thanks to an extension with a typo'd regex, my browser started replacing the word "keyboard" with "leopard".

==Trivia==
When first posted, the title of the comic was "s/keyboard/leopard" (the last forward slash after the word "leopard" was missing). This string would have failed had it actually been typed as a substitution regex. The title was later fixed.

{{comic discussion}}

[[Category:Substitutions]]
[[Category:Comics featuring Cueball]]
[[Category:Multiple Cueballs]]
[[Category:Wikipedia]]
[[Category:Internet]]
[[Category:Language]]
[[Category:Animals]]
[[Category:Regex]]
[[Category:Comics edited after their publication]]

887: Future Timeline

2025-08-10T12:45:22Z

Giraffequeries: Are we seriously going to wait for 2101 just to finish this? I have...some feeling about this wiki somehow lasting to that date.

{{comic
| number = 887
| date = April 18, 2011
| title = Future Timeline
| before = [[#Explanation|↓ Skip to explanation ↓]]
| image = future timeline.png
| titletext = Not shown: the approximately 30,000 identical, vaguely hysterical articles titled "WHITE PEOPLE IN [THE US/BRITAIN] TO BECOME MINORITY BY [YEAR]!", which came up for basically any year I put in.
}}

{{TOC}}

==Explanation==
This comic uses the same strategy as comic [[715: Numbers]], in which [[Randall]] uses Google to search for phrases and then charts the results. This one is charted as a timeline, whereas 715 was charted as line graphs.
It is a list of things predicted or announced by anyone at any time (the ones you see on Google search using "by the year..." or similar statements).

"2101 - War Was Beginning" is a reference to the opening narration of video game ''Zero Wing''; the same narration is famous for the internet meme "{{w|All your base are belong to us}}". As there are not any other out and out references in the comic, and the rest are actually results that you can find using Randall's methods, "War Was Beginning" was probably the only thing he got when he googled 2101 as well.

Certain events in this comic, e.g., "Social Security stops running surplus", are repeated multiple times. Also, certain bizarre events, like "Apocalypse occurs", or "Flying cars reach market", happen before rather plausible things, like "'Big one' hits California". Certain events, like "Japan is a robot-only country" or "Gillette introduces 14-blade razor" may be related to the recurring theme [[605: Extrapolating]].

According to [https://www.census.gov/content/dam/Census/library/publications/2020/demo/p25-1144.pdf some official projections], (non Hispanic) {{w|White people}} will no longer be the majority in the United States by 2045 due to low birth rates and high rates of immigration. The title text is Randall's statement that, for both the US and Great Britain, there are so many sources that mention this, for any year he cared to search for and many using more far more doubtful sources (if any), that he decided that it was not worth flooding the chart with all these spurious repetitions, even though he did include other less prolific recurring themes.

This comic has similar features to [[1413: Suddenly Popular]], [[1093: Forget]], and [[891: Movie Ages]].

==The predictions==

{| class="wikitable"
|-
! Year
! Prediction
! Further Details
! Outcome
|-
| rowspan="4"| 2012
| World population
| Ever since the advent of modern medicine and the more efficient agricultural processes developed since the Industrial Revolution, the human population had been growing at an unprecedented rate. This has caused some people to {{w|Human overpopulation|worry about overpopulation}}, which would cause a scarcity of resources and overcrowding, and propose various solutions, most of which involve some form of eugenics. 7 billion is a landmark number because it is a multiple of 1 billion.
| Close; Earth reached 7 billion in late 2011.
|-
| Flying cars
| For decades, flying cars have been a staple of futuristic sci-fi and technological predictions. So far very few of these predictions, which to tend to hover around 5–10 years from whatever the current date is, have come true.
| Too early; a flying car designed for consumer use was [https://www.suasnews.com/2021/04/announcing-aska-the-electric-take-off-and-landing-flying-car-for-consumers first demonstrated in July 2021] , but has yet to go into production. You could argue that helicopters count as flying cars, but these are not affordable{{citation needed}} and hence not widely used by the general public.
|-
| Canada cuts greenhouse emissions
| Currently, the Earth is experiencing an unprecedented period of warming we call global warming, caused in part by greenhouse emissions, which are gases that help trap heat in the atmosphere. Countries have repeatedly gotten together and promised to stop emitting greenhouse gases, but so far they have failed to meet their targets.
| False. Canada withdrew from the Kyoto treaty in late 2011, and its emissions in 2012 were 18% ''above'' 1990 levels (though its population had grown 26% and its GDP had grown 67% in that period).
|-
| Apocalypse occurs
| The end of a cycle of the Mayan calendar on December 22, 2012 has been used in popular culture as a basis for predicting the end of the world. Amongst other things, this included the film '2012'. Some people took this rather more seriously, and actually believed that the world would end on this date.
| False.{{Citation needed}}
|-
| rowspan="4"| 2013
| National debt paid off
| For years, the subject of national debt (in the USA) has been a political point of contention. While both parties theoretically support reducing the debt or paying it off entirely, Democrats are more willing to spend to pull the country out of recessions in the economy and Republicans to cut taxes. The last time that spending did not exceed revenue begin under Clinton, a Democrat, and ended after George W. Bush, a Republican, said that this amounted to taxpayers being "overcharged" and taxes were lowered, followed by the Great Recession. Clinton at one point proposed [https://money.cnn.com/1999/06/28/economy/clinton/ paying off the debt by 2015].
| False.
|-
| Microchipping all Americans
| Microchips are small computer chips, typically embedded in pets in case they get lost, that contain information about the pet. Some, more paranoid, people worry about the government microchipping everyone in an effort to monitor their activities.
| False, although voluntary RFID implants do exist.
|-
| Homelessness ended in MA
| In 2008, the Commission To End Homelessness in Massachusetts, under Governor Deval Patrick, proposed a plan to all but eliminate homelessness over the next five years (hence the 2013 end-date on the comic).
| False.
|-
| Health care reform law repealed
| A health care reform law, popularly known as Obamacare, was signed into law in 2010. Ever since, many Republicans have tried (in vain) to repeal it, disliking the idea that government should provide and require healthcare. However, President [[Joe Biden]] has stated to restore Obamacare.
| Too early; almost repealed in 2017.
|-
| rowspan="2"| 2014
| US leaves Afghanistan
| After the {{w|September 11 attacks|terrorist attack}} on the {{w|World Trade Center (1973–2001)|World Trade Center}} (WTC) in New York on September 11, 2001, the United States invaded Afghanistan, due to the Taliban allegedly hosting al-Qaeda, the terrorist organization behind the attacks. The war has gone on since then, with the public growing increasingly tired of it. Public support then favoured a withdrawal, but for military and logistical reasons, the government could not simply move all the US troops in Afghanistan to their home. Therefore, the government promised to eventually withdraw all troops, initially planned to do so by the end of 2014.
| Too early; the remaining US troops [https://www.ndtv.com/world-news/afghanistan-afghan-troops-struggle-to-replace-americans-at-key-bagram-air-base-2480356 left Afghanistan in June 2021.]
|-
| GNU/Linux dominant OS
| An operating system, or OS, is the software that forms the structure in which applications on you computer function. Some typical OSs include Mac OS X, Windows 10, and Linux. The first two of those three are commercial products, sold as a copy by a company. The last is an open-source OS, one that anyone can download and modify free. Typically, open-source software is used by a small number of socially conscious people.
| False, although Linux-based Android dominated phones since 2011.
|-
| rowspan="3"| 2015
| New Horizon reaches Pluto
| The New Horizon spacecraft is a U.S. space mission designed to go to Pluto and take photographs, collect samples, etc.
| True. [https://pluto.jhuapl.edu It reached Pluto on July 14, 2015].
|-
| Healthcare law causes hyperinflation
| The National Inflation Association warned that the [https://www.prnewswire.com/news-releases/healthcare-bill-to-cause-us-hyperinflation-by-2015-88711032.html healthcare bill would cause U.S. hyperinflation by 2015.]
| False.
|-
| Millennium development goals achieved
| {{w|Millennium Development Goals}}
| False.
|-
| rowspan="3"| 2016
| Baby boomers begin turning 65
| {{w|Baby boomers}} are individuals conceived in the years following World War Two, roughly defined as those born from 1946-1959. This isn't so much a prediction as basic math; if you were born in 1946, you turned 65 in 2011.
| True.
|-
| Android takes 38%/45% of market share
| {{w|Android (operating system)|Android}} is a popular operating system for smartphones and tablets, created by Google. Market share is the percentage of all devices that use the product, in this case the Android operating system. These entries together are humorous because they cannot both happen at the same time.
| Too late; passed these marks in 2010. {{w|Android OS}}'s [https://www.idc.com/prodserv/smartphone-os-market-share.jsp market share was already 84.4% as of the third quarter of 2014,] showing that both estimates were overly conservative.
|-
| Windows phone overtakes iOS
| {{w|iOS}} is the operating system used by Apple iPhones. At the time of the comic, Apple's mobile OS is much more popular than Microsoft's. The article Randall found predicts that the tables will turn. However, Windows Phone was discontinued in 2017, with support for the last version (Windows Phone 10) ending on December 10, 2019.
| False.
|-
| rowspan="5"| 2017
| China completes lunar mission
| The {{w|Chinese space program}} has plans for extraterrestrial exploration, including a manned mission to the Moon.
Already having had success (prior to the comic) with lunar orbiters from 2007 onwards, the first lunar lander was 14 December 2013. The mission that the comic describes, however, is the first sample-return mission that returned to Earth 16 December 2020 (later than this prediction).
| Too early.
|-
| Social Security stops running surplus
| The first of many predictions about the United States {{w|Social Security (United States)|Social Security}} trust fund program, all predicting its decline due to a variety of factors.
| Too early. Occurred in 2021.
|-
| US budget balanced
| The {{w|United States federal budget}} outlines how much the US government spends on what in a given fiscal year. The budget is not required to be balanced, and so often more money is spent than is earned in revenue, causing the national debt to rise.
| False. Still pretty negative.
|-
| Newspapers become obsolete and die out
| The increasing popularity of social media and online news has caused a steady decline in the popularity of print media.
| False. Though newspapers (especially printed ones) are in decline, they are certainly not obsolete as of 2017, or 2022, for that matter.
|-
| Cosmetic surgery doubles
| {{w|Cosmetic Surgery}}
| False. According to the ASPS (American Society of Plastic Surgeons), 1.6 million cosmetic surgeries were performed in 2011, while 1.8 million were performed in 2017, an increase of only 0.2 million.
|-
| rowspan="2"| 2018
| Social Security stops running surplus
| {{w|Social Security (United States)|Social Security}} again.
| Still too early.
|-
| Jesus returns to Earth
| A number of Christians have attempted to predict the return of Christ (a.k.a. the {{w|second coming}} or the rapture) using clues from The Bible, even though the Bible and other religious texts says that "no man can know the date" and that it would be within the lifetime of some who witnessed Jesus's first appearance. Several predicted dates have come and gone.
| False.
|-
| rowspan="2"| 2019
| Social Security stops running surplus
| {{w|Social Security (United States)|Social Security}} again.
| Still too early.
|-
| Every baby has genes mapped at birth
| {{w|Gene Mapping}}
| False.
|-
| rowspan="3"| 2020
| Solar power becomes cheaper than fossil fuels
| Scientists estimate that more than half of the {{w|fossil fuels}} in existence have already been found and that fossil fuel production will begin to decline due to the scarcity, causing prices to increase. At the same time, improvements in {{w|Solar Power|solar technology}} are causing the prices for solar energy to steadily decrease.
| True, though only in {{w|Cost of electricity by source#Recent_global_studies|certain cases}}.
|-
| Keyboards and mice become obsolete
| {{w|Computer input device|Computer input devices}} are beginning to adopt other inputs, such as trackpads, voice commands, touch screens, and eye tracking. While touch screens in particular are gaining widespread use with the rise of smartphones and tablets, as of 2022 desktop computers that use mice are still fairly common. And while voice-to-text has greatly improved, it still doesn't have the accuracy to replace typing. None of the other text inputs are as fast as a keyboard, and none are suitable for writing program code.
| False. While touchscreen devices ''are'' increasingly common, desktop computers are still very much in use. Mice continue to be used alongside touchscreens and trackpads, and keyboards remain the dominant method of writing on computers.
|-
| New Tappan Zee bridge constructed
| A {{w|Tappan_Zee_Bridge#Replacement_bridge|replacement bridge}} was announced in 2008.
| Too late; completed in 2017.
|-
| rowspan="4"| 2021
| US debt reaches 97% of GDP
| {{w|US Debt}}
| Too late; reached in 2011.
|-
| US unemployment falls to 2.8%
| {{w|Unemployment in the United States}}
| False: because of the COVID-19 pandemic, unemployment has actually ''increased''.
|-
| Restored caliphate unifies Middle East
| A {{w|caliphate}} is a form of {{w|Islam|Islamic}} theocracy, centred around a Caliph, or successor to the prophet {{w|Muhammad}}. This prediction foreshadows the Islamic State of Iraq and Syria (ISIS), which attempted but failed to create a caliphate in the Levant.
| False.
|-
| Lake Mead evaporates
| Formed by the {{w|Hoover Dam}} on the {{w|Colorado River}}, {{w|Lake Mead}} is the largest reservoir in the United States (measured by maximum capacity). It hasn't reached its capacity since 1983, due to drought and increased demand for water. This is linked to {{w|global warming}}.
| False, although water levels continue to fall.
|-
| rowspan="3"| 2022
| Kilimanjaro snow-free
| At 5,895 metres, {{w|Kilimanjaro}} is the highest mountain in {{w|Africa}}, and the highest free-standing mountain in the world. Around 85% of its ice cover disappeared between 1912 and 2011, and it continues to recede.
| False.
|-
| HTML 5 finished
| The World Wide Web Consortium (W3C) began work on {{w|HTML 5}} in 2004.
| Too late; 5.0 specification released in 2014, but incremental updates continue.
|-
| Newspapers become obsolete and die out
| This is the second time this prediction has appeared.
| False.
|-
| rowspan="3"| 2023
| Jesus returns to Earth (again)
| Again.
| False.
|-
| US debt passes 100% of GDP
| This references the common fear that {{w|US Debt}} will exceed GDP, possibly causing {{w|Economic bubble|economic turmoil}}.
| Too late; reached in 2012.
|-
| All unprotected ancient forests gone from Pacific Northwest
| Likely due to a combination of wildfire and {{w|deforestation}}.
| False.
|-
| rowspan="5"| 2024
| Atlantis begins to reappear
| {{w|Atlantis}} is the name of a fictional/hypothetical island, which is supposed to have been lost beneath the sea. It's not clear why ''rising'' sea level would make it reappear.
| False.
|-
| Orangutans extinct in wild
| {{w|Orangutan|Orangutans}} are a species of great ape, currently classed as an {{w|endangered species}}, and found only in the {{w|Rainforest|rainforests}} of {{w|Borneo}} and {{w|Sumatra}}.
| False.
|-
| China lands men and women on the Moon
| The {{w|Chinese space program}} has plans for extraterrestrial exploration, including a manned mission to the Moon.
Announcements in 2023 established that the Chinese crewed mission remains supposed to happen "by the year 2030".
| False
|-
| NASA sets up permanent Moon base
| There has been a lot of hype recently about finally returning to the Moon, vis-a-vis Orion.
| Too early; the {{w|Artemis program}} plans to put the {{w|Lunar Gateway}} in orbit around the Moon, which will be flown up in [https://www.nasa.gov/gateway-frequently-asked-questions four launches over the course of six years, beginning "no earlier than 2025"]
|-
| Female professionals pass males in pay
| This prediction is an erroneous extrapolation from the current (at the time this comic was made) rate at which female incomes were catching up to male incomes.
| False.
|-
| rowspan="4"| 2025
| World population reaches 8 billion
| Given current rates, it seems unlikely it will take this long to hit 8 billion, but advances in birth control options and especially their availability in developing nations may slow the current rate considerably.
| Too late. This number was reached in late 2022, although it may have been reached later as some countries overcount their population.
|-
| Two billion people face water shortages
| https://english.pravda.ru/science/earth/28-01-2008/103693-water_crisis-0/
| True. As of 2025, [https://sdgs.un.org/topics/water-and-sanitation 2.2 billion people face ongoing water shortages]. In addition, [https://www.science.org/doi/10.1126/sciadv.1500323 about 4 billion people face severe shortages at least one month per year].
|-
| 62 MPG cars introduced
| 62 miles per gallon, ~3.8 L/100km. 62 MPG is a very good mileage rate at today's standard, even though [https://abcnews.go.com/Business/story?id=5231050&page=1 some cars can be driven carefully so as to attain over 100 MPG].
|
|-
| US power fades
| https://www.cbsnews.com/news/report-us-power-will-fade-by-2025/
| Hard to know what the precise metric for this would be.
|-
| rowspan="5"| 2026
| Atlantis emerges completely
| {{w|Atlantis}} is the name of a fictional/hypothetical island, which is supposed to have been lost beneath the sea. It seems that it has taken 2 years for it to emerge completely.
|
|-
| Rock Bands die out
| https://bestbands.wordpress.com/2009/01/25/rock-bands-to-die-out-by-2026/
|
|-
| US debt paid off
| [https://www.nytimes.com/2011/03/27/business/27view.html It’s 2026, and the Debt Is Due.]
|
|-
| Car accidents cease
| Presumably, cars will be fully automated and able to pilot themselves at this point and will have fail-safes that prevent collisions currently attributed to user error. Car accidents will always be possible, however, due to mechanical and electrical failures.
|
|-
| West coast falls into ocean
| Most likely due to {{w|San_Andreas_Fault#The_next_.22Big_One.22|a significant seismic event}}.
|
|-
| rowspan="3"| 2027
| Japan introduces new fastest Maglev train
| Japan's railway systems are famous for their "bullet trains", or {{w|Shinkansen}}. The Chūō Shinkansen is planned to be opened in this year.
|
|-
| Lyndon Larouche-planned Mars colony is established
| https://totse.mattfast1.com/en/technology/space_astronomy_nasa/moonmars.html
|
|-
| Social Security stops running surplus
| {{w|Social Security (United States)|Social Security}} again.
|
|-
| rowspan="4"| 2028
| Tobacco outlawed
| Tobacco products (cigarettes and chewing tobacco) have become more and more taboo in modern culture, with most public places and private businesses forbidding their use indoors and near places children congregate.
|
|-
| 40% of coral reefs gone
| Many factors have been attributed to the decline of {{w|Coral_reef#Threats|coral reefs}}, including mining, over fishing, and rising ocean tempteratures.
|
|-
| US debt paid off
| {{w|US Debt}}
|
|-
| Social Security stops running surplus
| {{w|Social Security (United States)|Social Security}} again
|
|-
| rowspan="4"| 2029
| Social Security trust fund exhausted
| The next stage of the collapse of {{w|Social Security (United States)|Social Security}}. After years of deficits deplete the trust fund, the program will only be able to pay out as much in benefits as it takes in each year.
|
|-
| Computers pass the Turing test
| It is no coincidence that 2029 is the timeline for Terminator Movies.
| Some computer programs already clear the Turing Test about 30% of the time.
|-
| Aging reversed
| [https://www.zdnet.com/article/manhattan-beach-project-to-reverse-aging-by-2029/ Manhattan Beach Project to reverse aging by 2029]
|
|-
| Wikipedia reaches 30 million articles
|
| As of July 2024, Wikipedia has over [https://meta.wikimedia.org/wiki/List_of_Wikipedias#Grand_Total 63.2 million total articles], if all languages are included. The source being cited may have meant the English language Wikipedia, which has only {{w|Special:Statistics|6.8 million articles}}.
|-
| rowspan="3"| 2030
| Half of Amazon rain forest lost to logging
| WWF press release - [https://www.worldwildlife.org/press-releases/climate-change-speeds-up-amazon-s-destruction-says-wwf Climate Change Speeds Up Amazon’s Destruction] referring to a report on the [https://assets.panda.org/downloads/amazonas_eng_04_12b_web.pdf Amazon's vicious cycles].
|
|-
| Cancer deaths double from 2008 levels
| From the [https://www.cancer.org/myacs/newengland/global-cancer-burden-to-double-by-2030 Global Cancer Burden to Nearly Double by 2030] article about the article from page 37 of [https://www.cancer.org/research/cancerfactsfigures/globalcancerfactsfigures/global-facts-figures-2nd-ed Global Cancer Facts & Figures 2nd edition].
|
|-
| Arctic ice-free in summer
| https://news.nationalgeographic.com/news/2009/10/091015-arctic-ice-free-gone-video-ap.html
|
|-
| rowspan="3"| 2031
| Computers controlled by thought
| https://www.gizmag.com/future-mobile-technology/17554/
| As of 2017, this is {{w|Brain–computer interface|already possible}}, but still not used in any mass available devices as of 2024.
|-
| Realtors replaced by technology
| https://agbeat.com/editorials/will-realtors-be-replaced-by-technology-by-the-year-2031/
|
|-
| Social Security trust fund exhausted
| https://crfb.org/blogs/cbo-95-percent-confident-social-security-trust-fund-runs-out-25-years
|
|-
| rowspan="3"| 2032
| "Big One" hits San Francisco
| {{w|San Franscisco}} is located on the {{w|San Andreas Fault}}, which is predicted to produce a magnitude 7+ earthquake in the 'near future'. This event is referred to as {{w|San_Andreas_Fault#The_next_.22Big_One.22|"The Big One"}}.
|
|-
| US elects first married lesbian President
| https://4chandata.org/g/In-what-major-ways-do-you-think-the-world-of-2032-will-be-different-from-that-of-today-a20155
|
|-
| Entire world converted to Christianity
| https://www.goddiscussion.com/38920/christian-domininionsts-to-take-over-the-world-by-2032/
|
|-
| rowspan="3"| 2033
| Kilimanjaro ice disappears
| https://www.reuters.com/article/2009/11/02/idUSL2210825
|
|-
| India becomes superpower
| https://www.facebook.com/pages/India-A-SuperPower-by-2033/151177191568098
|
|-
| Europe reaches Mars
| [https://www.spacedaily.com/news/esa-general-03zb.html Specifically, a manned European mission]. ESA's {{w|Mars Express}} probe landed in 2003.
|
|-
| rowspan="2"| 2034
| US diabetes cases double, treatment costs triple
| [https://www.reuters.com/article/2009/11/27/us-diabetes-usa-costs-idUSTRE5AQ0C220091127 U.S. diabetes cases to double, costs triple by 2034]
|
|-
| US builds autonomous robot army
| The concept of robots built for military service is another common element of science fiction stories. [https://www.aos-inc.com/index.php/medialias/press-releases?id=112 Unmanned Systems] article, about the [https://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA522247 2009-2034 Unmanned Systems Integrated Roadmap] publication ([https://www.amazon.com/2009-Unmanned-Integrated-Aircraft-Technologies-ebook/dp/B0047743A0 details at Amazon]).
|
|-
| rowspan="3"| 2035
| 80% of America's energy comes from renewable sources
| From fact sheet on Obama's [https://www.whitehouse.gov/the-press-office/2011/01/25/fact-sheet-state-union-president-obamas-plan-win-future State of the Union.]
|
|-
| Himalayan glaciers down 80% in size
| From an IPCC report on [https://web.archive.org/web/20100116132657/https://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch10s10-6-2.html The Himalayan glaciers] that has been analysed in quite some depth. See for example detailed article on an [https://www.yaleclimateconnections.org/2010/02/anatomy-of-ipccs-himalayan-glacier-year-2035-mess/ anatomy of IPCC’s mistake].
|
|-
| Arctic sea lane opens
| [https://www.ft.com/cms/s/0/730ef8fe-27e1-11e0-8abc-00144feab49a.html#axzz3OBgEHYNY Arctic sea lane could open by 2035]
|
|-
| rowspan="2"| 2036
| 80% of US has access to high-speed rail
| [https://www.wnyc.org/story/284946-obama-80-percent-of-americans-should-have-access-to-high-speed-rail-by-2036/ Obama: 80 Percent of Americans Should Have Access to High Speed Rail By 2036]
|
|-
| Asteroid Apophis misses/hits Earth
| 99942 Apophis is a near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a probability of up to 2.7% that it would hit Earth on April 13, 2029.
|
|-
| rowspan="2"| 2037
| Arctic ice-free in September
| {{w|Arctic sea ice decline}}
|
|-
| Social Security trust fund exhausted
| {{w|Social Security (United States)|Social Security}}
|
|-
| rowspan="2"| 2038
| 32-bit timestamps roll over, causing Y2K-level chaos
| On 03:14:07 UTC on 19 January 2038, the value of time_t rolls over, that is it will return to zero. time_t is a computing standard measurement of time; it is a count of the number of seconds since 00:00:00 UTC on 1 January 1970. time_t is used by most computer systems to store date and time information. It is recommended that new software should convert to a 64 bit time_t; indeed, most operating systems designed to run on 64-bit hardware already use signed 64-bit time_t integers. This would give an epoch of 15:30:08 UTC on 4 December 292,277,026,596 (292 billion years away). Of course, legacy systems may not be upgradable so action taken now should prevent this becoming a problem closer to 2038...
|
|-
| "Big One" hits California
| [https://www.presstelegram.com/technology/20080414/the-big-one-likely-to-hit-by-2038 `The big one' likely to hit by 2038]
|
|-
| rowspan="3"| 2039
| US population hits 400 Million
| [https://www.prb.org/Publications/Articles/2008/us400million.aspx U.S. Population Projected to Hit 400 Million in 2039]
|
|-
| Severe heat waves become commonplace
| [https://news.stanford.edu/news/2010/july/extreme-heat-study-070810.html Heat waves and extremely high temperatures could be commonplace in the U.S. by 2039, Stanford study finds]
|
|-
| Scientology becomes majority religion in US
| [https://home.snafu.de/tilman/2039.html Essay: Scientology in the year 2039]
|
|-
| rowspan="2"| 2040
| Arctic summers ice-free
| [https://www.livescience.com/9419-arctic-summer-ice-free-2040.html Arctic Summer Could be Ice-Free by 2040]
|
|-
| Nanotechnology makes humans immortal
| [https://www.computerworld.com/article/2528330/app-development/nanotech-could-make-humans-immortal-by-2040--futurist-says.html Nanotech could make humans immortal by 2040, futurist says]
|
|-
| 2041
| Social Security trust fund exhausted
| {{w|Social Security (United States)|Social Security}}
|
|-
| 2043
| World population passes 9 Billion
| {{w|Population growth}}
|
|-
| rowspan="2"| 2044
| Mankind genetically engineered to be happy
| Premise of the movie [https://www.imdb.com/title/tt1363468/ Zenith] - further details are in the [https://www.filmjournal.com/filmjournal/content_display/esearch/e3i25130cd57f1590bda4527c098ac85b01 film review for Zenith.]
|
|-
| Childhood obesity reaches 100%
| [https://www.ivanhoe.com/channels/p_channelstory.cfm?storyid=11414 100-Percent Childhood Obesity Predicted by 2044]
|
|-
| 2045
| Humans and machines merge
| {{w|Ray Kurzweil}} predicts of a 'singularity' which will lead to a race of super intelligent beings.
|
|-
| 2046
| World's natural resources depleted
| [https://raphaelvanlaer.wordpress.com/2012/02/22/peak-uncertainty-when-will-we-run-out-of-fossil-fuels/ Peak uncertainty, when will we run out of fossil fuels?]
|
|-
| rowspan="3"| 2047
| World ruled by banks and corporations
| [https://www.amazon.co.uk/Future-Schlock-2047-RM-Krakoff-ebook/dp/B0039IT37Q Future Schlock - the story of a world turned upside down in 2047]
|
|-
| Tobacco industry fails
| [https://www.news.wisc.edu/16857 Experts: Big Tobacco dead by 2047, possibly sooner]
|
|-
| US begins using autonomous attack drones
| [https://www.theguardian.com/world/2009/aug/22/us-air-force-drones-pilots-afghanistan US Air Force prepares drones to end era of fighter pilots]
|
|-
| rowspan="3"| 2048
| Salt-water fish extinct from overfishing
| WWF report on [https://wwf.panda.org/about_our_earth/blue_planet/problems/problems_fishing/ unsustainable fishing.]
|
|-
| Unisex bathing suits cover body from shoulder to ankle
| [https://future.wikia.com/wiki/RyansWorld:_Bathing_Suits_of_the_Future RyansWorld: Bathing Suits of the Future]
|
|-
| Entire US population overweight
| [https://web.archive.org/web/20090321075605/https://thestatsblog.wordpress.com/2008/07/29/scientists-say-thin-people-face-extinction-in-united-states-everyone-will-be-overweight-by-2048-%E2%80%93-and-less-smart Scientists Say Thin People Face Extinction in United States: Everyone Will Be Overweight by 2048 – And Less Smart (archive)]
|
|-
| rowspan="3"| 2049
| $1,000 computer exceeds computational ability of humanity
| [https://www.americanbar.org/content/newsletter/publications/technology_e_report_home/2007_may_technotes.html TechNotes: Trends in Technology]
|
|-
| Singularity occurs
| [https://www.prismdecision.com/the-singularity-is-near The Singularity Is Near]
|
|-
| Fishing industry collapses
| This tends to happen when your food-stock is extinct{{citation needed}} - see WWF report on [https://wwf.panda.org/about_our_earth/blue_planet/problems/problems_fishing/ unsustainable fishing.]
|
|-
| rowspan="5"| 2050
| 80% of Earth's population lives in urban centers
| [https://infochangeindia.org/population/books-a-reports/80-of-world-population-will-soon-be-in-urban-areas.html 80% of world population will soon be in urban areas]
|
|-
| China controls space
| [https://books.google.com/books?id=op851Uf99LQC&dq=China+controls+space+2050&source=gbs_navlinks_s Space Science & Technology in China: A Roadmap to 2050]
|
|-
| Sex with robots possible
| [https://www.livescience.com/1951-forecast-sex-marriage-robots-2050.html Forecast: Sex and Marriage with Robots by 2050]
|
|-
| Cars banned from European cities
| [https://www.telegraph.co.uk/motoring/news/8411336/EU-to-ban-cars-from-cities-by-2050.html EU to ban cars from cities by 2050]
|
|-
| One million species extinct from climate change
| [https://news.nationalgeographic.com/news/2004/01/0107_040107_extinction.html By 2050 Warming to Doom Million Species, Study Says]
|
|-
| 2051
| Atmosphere escapes into space
| [https://www.thehulltruth.com/boating-outdoor-photos/255705-have-you-ever-seen-fallstreak-hole.html Conspiracy theory] relating to {{w|Fallstreak hole}} or hole punch clouds.
|
|-
| 2052
| Medicare, Medicaid, and Social Security spending exceed total US revenue
| {{w|Social Security (United States)|Social Security}}
|
|-
| rowspan="3"| 2053
| US budget balanced
| [https://crfb.org/blogs/omb-releases-long-term-projections-fy2015-budget-proposal OMB releases long-term projections for the FY2015 budget proposal]
|
|-
| Majority of Americans in prison
| [https://articles.philly.com/1992-06-14/news/26032105_1_prison-officials-prison-time-prison-commissioners 'Beyond Bricks And Bars' As Jails Overflow, The Lock-'em-up Credo Is Drawing Unlikely Criticism - From Prison Officials Themselves]
|
|-
| Cars driven by dogs
|
| This has [https://www.youtube.com/watch?v=BWAK0J8Uhzk already occurred] in 2012! However, it is not as widespread as the prediction may be implying.
|-
| 2054
| Hunger becomes unimaginable global problem
| [https://www.albionmonitor.com/0403a/earth2054.html Hunger Could Be 'Unimaginable' Global Problem By 2054]
|
|-
| rowspan="3"| 2055
| Atmospheric CO2 doubled
| [https://cmi.princeton.edu/wedges/flash_intro.php Carbon Mitigation Initiative: Stabilization Wedges]
|
|-
| Oil runs out
| [https://raphaelvanlaer.wordpress.com/2012/02/22/peak-uncertainty-when-will-we-run-out-of-fossil-fuels/ Peak uncertainty, when will we run out of fossil fuels?]
|
|-
| Copper, tin, lead, gold, and nickel all exhausted
| [https://www.environmentalgraffiti.com/environment/5-valuable-metals-that-could-vanish-by-2055 5 Valuable Metals That Could Vanish by 2055]
|
|-
| rowspan="2"| 2056
| RFID-tagged driverless cars
| [https://www.zdnet.com/article/rfid-tagged-driverless-cars-on-roads-by-2056/ RFID-tagged driverless cars on roads by 2056]
|
|-
| Robots given same rights as humans
| [https://www.cc.gatech.edu/news/robots-given-same-rights-humans-2056 Robots Given Same Rights As Humans By 2056]
|
|-
| rowspan="2"| 2057
| 150 Japanese settlers on Mars
| [https://connection.ebscohost.com/c/articles/9011051292/will-japan-colonize-mars Will Japan colonize Mars?]
|
|-
| Colorado River runs dry
| [https://news.agu.org/press-release/colorado-river-reservoirs-could-bottom-out-from-warming-business-as-usual/ Colorado River Reservoirs Could Bottom Out From Warming]
|
|-
| 2058
| Smoking ends in New Zealand
| [https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10698966 Smoking to die out in NZ by 2058]
|
|-
| 2059
| Humans have domesticated robots
| [https://diehardempiricist.blogspot.co.nz/2012/05/6-may-2011-virtual-necking-demography.html Virtual necking, demography, and robots]
|
|-
| rowspan="4"| 2060
| Human race lives in peace
| [https://www.arasfoundation.org/vision.html ARAS vision/mission]
|
|-
| Extreme droughts across much of Earth
| [https://wdas.cosmosmagazine.com/news/extreme-drought-across-most-earth-30-years/ Extreme drought across most of Earth by 2060]
|
|-
| Global temperature rise reaches 4 °C
| {{w|Avoiding dangerous climate change}}
|
|-
| Oil runs out again
| [https://business.financialpost.com/2011/04/01/oil-may-run-out-by-2060-hsbc/?__lsa=98a7-5c61 Oil may run out by 2060: HSBC]
|
|-
| 2061
| Halley's comet returns
| Halley's comet returns to the inner solar system (the vicinity of earth and the sun) every 75.3 years. The last time it was near earth was in 1985-1986. When it next returns, its closest approach to the sun will occur on [https://ssd.jpl.nasa.gov/horizons.cgi 28 July 2061.]
|-
| rowspan="2"| 2062
| Uganda hosts World Cup
| [https://shillingscents.blogspot.co.nz/2010/07/uganda-to-host-world-cup-in-2062.html Uganda to host world cup in 2062]
|
|-
| The Jetsons
| {{w|The Jetsons}} was an animated science fiction sitcom that first aired in 1962. The show was set in the year 2062.
|
|-
| rowspan="4"| 2063
| First human clones reach adulthood
| [https://au.ign.com/articles/2004/04/28/the-fall-last-days-of-gaia-diary-2 The Fall - Last Days of Gaia Diary #2]
|
|-
| Population of Moon reaches 100,000
| Reading Eagle newspaper article from July 17, 1963 - [https://news.google.com/newspapers?nid=1955&dat=19630717&id=PhgrAAAAIBAJ&sjid=B50FAAAAIBAJ&pg=4055,6599008 Moon Population of 100,000 Is Predicted for 2063] and [https://www.paleofuture.com/blog/2008/3/14/air-force-predictions-for-2063-1963.html Air Force Predictions for 2063 (1963)]
|
|-
| Population of Mars reaches 10,000
| [https://www.paleofuture.com/blog/2008/3/14/air-force-predictions-for-2063-1963.html Air Force Predictions for 2063 (1963)]
|
|-
| Spacecraft exceed speed of light
| Physics as currently understood states that it is impossible to exceed the speed of light. A monumental shift in our physics would have had to have occurred for this to come true. This is a reference to the 8th Star Trek feature Film: "Star Trek: First Contact" where Zefram Cochrane performs the first human Warp Flight on April 5, 2063.
|
|-
| 2064
| Clean Air Act finishes reducing haze in national parks to natural levels
| [https://www.cleanhouston.org/air/features/hazyfuture.htm State plan guarantees a hazy future for Texas’ wilderness areas]
|
|-
| rowspan="2"| 2065
| Last coral reefs die out
| From an [https://www.edgeofexistence.org/coral_reef_conservation/coral_reef_video.php article about a video called Reefs on the Edge] set in 2065 where a 15-year-old girl tells her grandfather's stories of coral reefs, and their demise.
|
|-
| Chernobyl cleanup complete
| [https://rt.com/politics/chernobyl-clean-in-55-years-time/ Chernobyl clean in 55 years time?]
|
|-
| 2066
| Cyprus achieves its goal
| This is from some [https://www.cyprus-forum.com/cyprus33608-110.html#p665612 forum posts on the decendants of Cypriots] that lends support to the autonomy of Cyprus from Greek or Turkey.
|
|-
| rowspan="2"| 2067
| Americans live in domed cities and watch 3D TV
| The article at [https://blogs.lib.unc.edu/ncm/index.php/2013/11/15/artifact-of-the-month-slide-rule-1916/ Artifact of the Month: Slide rule, 1916] includes information from the International Slide Rule Museum that "in 1967, Keuffel & Esser Co. commissioned a study of the future, predicting that Americans in 2067 would live in domed cities and watch 3D television."
|
|-
| Redheads go extinct
| [https://science.howstuffworks.com/life/genetic/redhead-extinction.htm Are redheads going extinct?]
|
|-
| rowspan="3"| 2068
| Ozone hole over Antarctic finishes recovering
| [https://www.theozonehole.com/recovery.htm NASA Study Finds Clock Ticking Slower On Ozone Hole Recovery]
|
|-
| Lord Jesus rules the Earth from Throne in Jerusalem.
| [https://myth-one.com/chapter_8.htm The Resurrections -- What Really Happens]
|
|-
| Entire world population gay due to chemicals in the water
| [https://thedailybanter.com/2013/01/alex-jones-the-government-is-trying-to-make-more-gay-people/ Alex Jones talks about chemicals that make people gay]
|
|-
| 2069
| Public masturbation legalized
| [https://uncyclopedia.com/wiki/UnNews:It's_still_not_okay_to_Pull_Your_Penis_out_in_Public It's still not okay to Pull Your Penis out in Public]
|
|-
| rowspan="3"| 2070
| World population peaks
| [https://www.newscientist.com/article/dn1108-global-population-to-peak-in-2070.html Global population to peak in 2070]
|
|-
| City-scale flooding disasters
| [https://www.telegraph.co.uk/news/earth/earthnews/3317033/City-scale-flooding-disasters-predicted-by-2070.html City-scale flooding disasters predicted by 2070]
|
|-
| 60% of world's energy comes from renewable sources
| [https://www.ssisolarenergy.com/solar-alternative-energy/ What Is Alternative Energy All About?]
|
|-
| rowspan="2"| 2071
| Europe's temperatures rise by 3 °C
| [https://www.umweltbundesamt.de/en/topics/climate-energy/climate-change-adaptation/adaptation-tools/project-catalog/peseta-projection-of-economic-impacts-of-climate Projection of Economic impacts of climate change in Sectors of the European Union based on bottom-up Analysis]
|
|-
| World summer temperatures rise by 5 °C
| [https://www.climateadaptation.eu/denmark/climate-change/ See "Air temperature changes in the 21st century"]
|
|-
| 2072
| US retirement age is set to 75
| [https://money.usnews.com/money/retirement/articles/2012/06/11/how-high-will-the-retirement-age-go Up to 70-80 years]
|
|-
| 2073
| Oceans do not rise one foot
| [https://www.skepticalscience.com/sea-level-rise-predictions.htm More like 2 feet]
|
|-
| rowspan="2"| 2074
| Number of 100-year-olds reaches one million
| [https://www.highbeam.com/doc/1P2-8848188.html UK to have 1 million centenarians by 2074]
|
|-
| Supertyphoons hit Japan
| [https://www.japantimes.co.jp/news/2009/09/08/national/super-typhoons-in-store-as-seas-warm/ Super typhoons in store as seas warm]
|
|-
| 2075
| US retirement age set to 69
| [https://www.csmonitor.com/Business/Latest-News-Wires/2010/1112/Retirement-age-at-69-Deficit-plan-hits-Social-Security Retirement age at 69? Deficit plan hits Social Security]
|
|-
| rowspan="2"| 2076
| Average scientific paper has more than 24 authors
| [https://doclib.uhasselt.be/dspace/bitstream/1942/871/1/yitzhaki373.PDF Multiple Authorship in Biochemistry and Other Fields] (PDF)
|
|-
| Social Security trust fund exhausted
| {{w|Social Security (United States)|Social Security}}
|
|-
| 2078
| Newspapers become obsolete and die out
| The same prediction was made for 2017 and 2022. Even when most prognosticators agree that something will happen, there can still be much disagreement about ''when'' it will happen.
|
|-
| rowspan="4"| 2079
| US debt reaches 716% of GDP
| {{w|US Debt}}
|
|-
| Lodgepole pines disappear from Northwest
| [https://oregonstate.edu/ua/ncs/archives/2011/feb/climate-change-causing-demise-lodgepole-pine-western-north-america Climate change causing demise of lodgepole pine in western North America]
|
|-
| Floods commonplace
| [https://www.sciencedaily.com/releases/2009/01/090108101627.htm Floods To Become Commonplace By 2080]
|
|-
| Religion marginalized
| https://www.bbc.com/news/uk-11347073
|
|-
| rowspan="2"| 2080
| Federal spending reaches 70% of GDP
| [https://crfb.org/sites/default/files/our_debt_problems_are_far_from_solved_updated_2.pdf Our debt problems are far from solved] (PDF)
|
|-
| UK population doubles
| [https://forums.canadiancontent.net/international-politics/69603-britains-population-hit-110-million.html Britain's population to hit 110 million]
|
|-
| 2082
| World population declines to one billion
| [https://www.paulchefurka.ca/Population.html Population: The Elephant in the Room]
|
|-
| 2084
| Robot policemen introduced
| [https://www.thetechherald.com/articles/Robotic-cops-set-to-stamp-out-crime-by-2084 Robotic cops set to stamp out crime by 2084]
|
|-
| 2085
| US deficit reaches 62% of GDP
| [https://moneybob.com/2010/06/28/paul-krugman-throws-in-towel-says-were-headed-for-another-depression/ Paul Krugman Throws In Towel, Says We’re Headed For Another Depression]
|
|-
| 2088
| Japan becomes all-robot country
| [https://www.theretributioners.tv/erics-blog/2009/11/25/-japan-to-become-all-robot-country-by-2088.html Japan To Become All Robot Country By 2088]
|
|-
| 2089
| World halts fossil fuel use
| {{w|Fossil Fuels}}
|
|-
| rowspan="2"| 2090
| Global warming hits 7 °C
| [https://www.reportingclimatescience.com/news-stories/article/models-warn-of-7c-dangerous-climate-change-by-2090.html Models warn of 7C dangerous climate change by 2090]. Climate change, especially global warming, is a [[:Category:Climate change|recurring theme]] in xkcd.
|
|-
| Global warming hits 4 °C
| Summarized [https://www.global-warming-forecasts.com/2090-climate-change-global-warming-2090.php here]. In reference to Andy Bowers, “Analysis: Scientists say global warming could affect California's drinking water supply,” NPR All Things Considered, June 22, 2001
|
|-
| rowspan="11"| 2100
| Global warming around 5-7 °C
| [https://grist.org/article/bau-fd/ Hadley Center study warns of ‘catastrophic’ 5-7°C warming by 2100 on current emissions path]
|
|-
| Sea levels have risen by a meter or more
| {{w|Future sea level}}
|
|-
| Joshua trees nearly extinct
| [https://news.discovery.com/earth/joshua-trees-climate-change-110325.htm Joshua Trees Nearly Wiped Out by 2100?]
|
|-
| Earth's climate resembles that of the Cretaceous
| [https://www.pnas.org/content/107/2/576 Atmospheric CO2 concentrations during ancient greenhouse climates were similar to those predicted for A.D. 2100]
|
|-
| Germany tropical
| [https://www.spiegel.de/international/spiegel/climate-change-predictions-a-tropical-germany-by-2100-a-463378.html Climate Change Predictions: A Tropical Germany by 2100?]
|
|-
| Emperor penguins extinct
| [https://news.bbc.co.uk/2/hi/science/nature/7851276.stm Emperor penguins face extinction]
|
|-
| Arctic permafrost thaws
| [https://www.scientificamerican.com/article/surface-permafrost-could/ Surface Permafrost Could Disappear by 2100]
|
|-
| Rising seas flood coastal cities
| [https://uanews.org/story/rising-seas-will-affect-major-us-coastal-cities-2100 Rising Seas Will Affect Major U.S. Coastal Cities by 2100]
|
|-
| Rain forests mostly gone due to climatic shifts
| [https://www.dailykos.com/story/2010/08/06/890970/-Massive-Loss-of-Rainforest-Species-by-2100-eKos-Earthship-Friday Massive Loss of Rainforest Species by 2100]
|
|-
| All coral reefs gone
| [https://planetsave.com/2010/10/15/coral-reefs-gone-by-2100/ Coral Reefs Gone by 2100?]
|
|-
| Gillette introduces 14-bladed razor
| Each iteration of the Gillette line of safety razors has one more blade than the previous one. MadTV has also [https://www.youtube.com/watch?v=2FAP8o5ZEo0 parodied] this. Over five years before MadTV did so, the Australian comedy group the D-Generation parodied the first two-bladed razor as the [https://www.youtube.com/watch?v=YleuLyCUx28 Gillette 3000] with 16 blades.
|
|-
| 2101
| WAR WAS BEGINNING
| References {{w|Zero Wing}}, a 1989 Japanese computer game set in 2101, famous for poorly translated English and the source for "{{w|All your base are belong to us}}". See [[286: All Your Base]]
|
|}

==Transcript==

:<big>'''THE FUTURE'''</big>
:'''According to Google search results'''
:Events for each year determined by the first page of Google search results for the phrases:
:"By <year>" "In year"
:"By the year <year>" "In the year <year>"
:"Will * by the year <year>" "Will * in the year <year>"
:"In <year>, * will" "By <year>, * will"
:
:;2012
::World population reaches 7 billion
::Flying cars reach market
::Canada cuts greenhouse emissions to 6% below 1990 levels as per Kyoto
::Apocalypse occurs
:;2013
::National debt paid off through President Clinton's plans
::Microchipping of all Americans begins
::Homelessness ended in Massachusetts
::Health care reform law repealed
:;2014
::US leaves Afghanistan
::GNU/Linux becomes dominant OS
:;2015
::New Horizons reaches Pluto
::Health care law causes hyperinflation
::192 UN member nations achieve millennium development goals:
::*Extreme poverty and hunger eradicated
::*Universal primary education implemented
::*Women empowered, gender equality reached
::*Environmental stability ensured
:;2016
::Baby boomers begin turning 65
::Android takes 38% of the smartphone market
::Android takes 45% of the smartphone market
::Windows Phone overtakes iOS in smartphones
:;2017
::China completes unmanned Lunar sample-return mission
::Social Security stops running surplus
::US budget balanced
::Newspapers become obsolete and die out
::Cosmetic surgery doubles
:;2018
::Social Security stops running surplus
::Jesus returns to Earth
:;2019
::Social Security stops running surplus
::Every baby has genes mapped at birth
:;2020
::Solar power becomes cheaper than fossil fuels
::Keyboards and mice become obsolete
::New Tappan Zee bridge constructed
:;2021
::US debt reaches 97% of GDP
::US unemployment falls to 2.8%
::Restored caliphate unifies Middle East
::Lake Mead evaporates
:;2022
::Kilimanjaro snow-free
::HTML 5 finished
::Newspapers become obsolete and die out
:;2023
::Jesus returns to Earth (again)
::US debt passes 100% of GDP
::All unprotected ancient forests gone from Pacific Northwest
:;2024
::Atlantis begins to reappear
::Orangutans extinct in wild
::China lands men and women on the moon
::NASA sets up permanent moon base
::Female professionals pass males in pay
:;2025
::World population reaches 8 billion
::Two billion people face water shortages
::62 MPG cars introduced
::US power fades
:;2026
::Atlantis emerges completely
::Rock Bands die out
::US debt paid off
::Car accidents cease
::West coast falls into ocean
:;2027
::Japan introduces new fastest maglev train
::Lyndon Larouche-planned Mars colony established
::Social Security stops running surplus
:;2028
::Tobacco outlawed
::40% of coral reefs gone
::US debt paid off
::Social Security stops running surplus
:;2029
::Social Security trust fund exhausted
::Computers pass the Turing Test
::Aging reversed
::Wikipedia reaches 30 million articles
:;2030
::Half of Amazon rain forest lost to logging
::Cancer deaths double from 2008 levels
::Arctic ice-free in summer
:;2031
::Computers controlled by thought
::Realtors replaced by technology
::Social Security trust fund exhausted
:;2032
::"Big One" hits San Francisco
::US elects first married lesbian president
::Entire world converted to Christianity
:;2033
::Kilimanjaro ice disappears
::India becomes superpower
::Europe reaches Mars
:;2034
::US diabetes cases double, treatment costs triple
::US builds autonomous robot army
:;2035
::80% of America's energy comes from renewable sources
::Himalayan glaciers down 80% in size
::Arctic sea lane opens
:;2036
::80% of US has access to high-speed rail
::Asteroid Apophis hits/misses Earth
:;2037
::Arctic ice-free in September
::Social Security trust fund exhausted
:;2038
::32-bit timestamps role over, causing Y2K-level chaos
::"Big One" hits California
:;2039
::US population hits 400 million
::Severe heat waves become commonplace
::Scientology becomes majority religion in US
:;2040
::Arctic summers ice-free
::Nanotechnology makes humans immortal
:;2041
::Social Security trust fund exhausted
:;2042
:;2043
::World population passes 9 billion
:;2044
::Mankind genetically engineered to be happy
::Childhood obesity reaches 100%
:;2045
::Humans and machines merge
:;2046
::World's natural resources depleted
:;2047
::World ruled by banks and corporations
::Tobacco industry fails
::US begins using autonomous attack drones
:;2048
::Salt-water fish extinct from overfishing
::Unisex bathing suits cover body from shoulder to ankle
::Entire US population overweight
:;2049
::$1.000 computer exceeds computational ability of humanity
::Singularity occurs
::Fishing industry collapses
:;2050
::80% of Earth's population lives in urban centers
::China controls space
::Sex with robots possible
::Cars banned from European cities
::One million species extinct from climate change
:;2051
::Atmosphere escapes into space
:;2052
::Medicare, Medicaid, and Social Security spending exceed total US revenue
:;2053
::US budget balanced
::Majority of Americans in prison
::Cars driven by dogs
:;2054
::Hunger becomes unimaginable global problem
:;2055
::Atmospheric CO2 doubled
::Oil runs out
::Copper, tin, lead, gold, and nickel all exhausted
:;2056
::RFID-tagged driverless cars
::Robots given same rights as humans
:;2057
::150 Japanese settlers on Mars
::Colorado River runs dry
:;2058
::Smoking ends in New Zealand
:;2059
::Humans have domesticated robots
:;2060
::Human race lives in peace
::Extreme droughts across much of Earth
::Global temperature rise reaches 4°C
::Oil runs out again
:;2061
::Halley's comet returns
:;2062
::Uganda hosts World Cup
::The Jetsons
:;2063
::First human clones reach adulthood
::Population of Moon reaches 100,000
::Population of Mars reaches 10,000
::Spacecraft exceed speed of light
:;2064
::Clean Air Act finishes reducing haze in national parks to natural levels
:;2065
::Last coral reefs die out
::Chernobyl cleanup complete
:;2066
::Cyprus achieves its goal
:;2067
::Americans live in domed cities and watch 3D TV
::Redheads go extinct
:;2068
::Ozone hole over Antarctic finishes recovering
::Lord Jesus rules the Earth from Throne in Jerusalem.
::Entire world population gay due to chemicals in the water
:;2069
::Public masturbation legalized
:;2070
::World population peaks
::City-scale flooding disasters
::60% of world's energy comes from renewable sources
:;2071
::Europe's temperatures rise by 3°C
::World summer temperatures rise by 5°C
:;2072
::US retirement age is set to 75
:;2073
::Oceans do not rise one foot
:;2074
::Number of 100-year-olds reaches one million
::Supertyphoons hit Japan
:;2075
::US retirement age set to 69
:;2076
::Average scientific paper has more than 24 authors
::Social Security trust fund exhausted
:;2077
:;2078
::Newspapers become obsolete and die out
:;2079
::US debt reaches 716% of GDP
::Lodgepole pines disappear from Northwest
::Floods commonplace
::Religion marginalized
:;2080
::Federal spending reaches 70% of GDP
::UK population doubles
:;2081
:;2082
::World population declines to one billion
:;2083
:;2084
::Robot policemen introduced
:;2085
::US deficit reaches 62% of GDP
:;2086
:;2087
:;2088
::Japan becomes all-robot country
:;2089
::World halts fossil fuel use
:;2090
::Global warming hits 7°C
::Global warming hits 4°C
:;2091
:;2092
:;2093
:;2094
:;2095
:;2096
:;2097
:;2098
:;2099
:;2100
::Global warming around 5-7°C
::Sea levels have risen by a meter or more
::Joshua trees nearly extinct
::Earth's climate resembles that of the Cretaceous
::Germany tropical
::Emperor penguins extinct
::Arctic permafrost thaws
::Rising seas flood coastal cities
::Rain forests mostly gone due to climatic shifts
::All coral reefs gone
::Gillette introduces 14-bladed razor
:;2101
::WAR WAS BEGINNING

{{comic discussion}}

[[Category:Large drawings]]
[[Category:Timelines]]
[[Category:Google Search]]
[[Category:Earthquakes]]
[[Category:Climate change]]
[[Category:Singularity]]
[[Category:Renewable energy]]
[[Category:Smartphones]]
[[Category:Wikipedia]]

Talk:3120: Geologic Periods

2025-07-25T22:54:52Z

Giraffequeries: made a comment. Did I do this right?

Discovered this explanation fresh off the griddle. The transcript doesn't even exist yet wow. Also, hi! This is my first time commenting! Did I do it right? [[User:Giraffequeries|Giraffequeries]] ([[User talk:Giraffequeries|talk]]) 22:54, 25 July 2025 (UTC)

2990: Late Cenozoic

2025-07-22T11:20:37Z

Giraffequeries: Fixed the transcript, hopefully this is what the explainxkcd gods said by "fixing" (gave the aliens themselves a description, other small edits etc etc)

{{comic
| number = 2990
| date = September 25, 2024
| title = Late Cenozoic
| image = late_cenozoic_2x.png
| imagesize = 303x396px
| noexpand = true
| titletext = Our nucleic acid recovery techinques found a great deal of homo sapiens DNA incorporated into the fossils, particularly the ones containing high levels of resin, leading to the theory that these dinosaurs preyed on the once-dominant primates.
}}

==Explanation==
A major part of understanding how life-forms existed and operated in the past involves finding fossilized remains, and working out a timeline of when they lived, based on the sediment layers in which they were found (among other factors). Modern paleontology has resulted in many of these fossilized remains being dug up and assembled into complete skeletons, which are frequently put on display in museums and other facilities.

This comic posits a future in which the remains of current civilization become buried in sediment, likely as a result of humanity going extinct so as to allow the premise of this comic to occur. Modern science estimates nearly all human-made activity - glass, concrete, steel - would erase to nothing within at most 1000 years (see ''Life After People'' and ''The World Without Us''), meaning that any future life-forms, extraterrestrial or evolved modern-day species, would be hard pressed to find anything that suggested this planet used to be inhabited by humans, save for some microplastics, [https://www.youtube.com/watch?v=8fADp43wJwU nuclear waste] and, in this scenario, preserved dinosaur bones, apparently.

While a question may arise as to why exactly no dinosaur fossils can be found in the intervening ~66 million years (which we know is because they went extinct and later ones were actually dug up by a different species), the real-life fossil record is quite sporadic, meaning such gaps should not be seen as unusual (these gaps are termed {{w|Lazarus taxon}}s).

The title of the strip refers to the {{w|Cenozoic}} era, which is the current geological era. The term "late Cenozoic" implies some geological change would occur significant enough to warrant designating a new era; either these changes led to the end of human civilization or are in fact spurred by them.

The title text says that a high amount of resin and human DNA found in these fossils led to them theorizing dinosaurs ate humans. When reconstructing fossils, resin is often used to recreate missing or incomplete bones amongst other purposes in assembling and displaying a "complete" skeleton. Since this resin is made and mixed by humans,{{Citation neededT}} incidental human DNA sources (such as cast off skin cells and hair) almost certainly get mixed in, leading to this misconception.

A similar museum, misunderstood by humans instead of this other species, is depicted in [[2760: Paleontology Museum]].

==Transcript==

:[Three aliens sit in a classroom. Each of the aliens has an oval-ish body ending in multiple tentacles, striped eye stalks ending in eyes with an iris and pupil, and a small mouth represented by a few vertical, close-together lines. One alien sits on a desk in front of a board covered with minute text and drawings of a T-Rex and a (presumably) Triceratops skeleton. Two aliens sit on stools equally high as the desk watching the teacher alien. The teacher alien on the left points at the board with one tentacle.]
:Left alien: Species such as triceratops and tyrannosaurus became more rare after the Cretaceous, but they survived to flourish in the late Cenozoic, 66 million years later.
:Left alien: Many complete skeletons have been discovered from this era.

:[Caption below the panel:]
:It's going to be really funny when our museums get buried in sediment.

==Trivia==
The title text has a typo: "techinques" should be "techniques".

The future beings are presumably ones that took over the far future of the Earth long after the extinction of humans. They are possibly descendents of one or other of the {{w|cephalopod}}s, species widely noted for their intelligence even today, but also bear a passing resemblence to the 'contemporary' [[2572: Alien Observers|alien life-forms]] that [[Randall]] uses for comics set in the current era.

Their relationship with his other [[1747: Spider Paleontology|beings from the future]], seen occasionally, is uncertain. That other form may merely be an 'avatar' presence, made necessary by the time-travel (or visitation) method in use, or else a representative from a [[1450: AI-Box Experiment|predominantly non-biological]] era of the future. 

{{comic discussion}}

[[Category:Aliens]]
[[Category:Dinosaurs]]
[[Category:Geology]]

2881: Bug Thread

2025-07-18T21:56:13Z

Giraffequeries: forgot to remove incomplete tag in last edit lol

{{comic
| number = 2881
| date = January 15, 2024
| title = Bug Thread
| image = bug_thread_2x.png
| imagesize = 317x495px
| noexpand = true
| titletext = After some account issues, we've added 6 new people from the beach house rental website support forum.
}}

==Explanation==

A bug thread is an online discussion about unintended behavior in a program, also known as a {{w|Software bug|bug}}. Bug threads may be found on bug trackers, such as Github or Bugzilla, on technical forums such as StackOverflow, or on general product user forums.

Most bug threads have a rule to only leave a comment if you have something insightful to add,{{Actual citation needed}} such as being able to reproduce how the bug occurs or possible solutions to resolving it. In practice, this rule is often ignored and many threads end up with multiple people simply commenting that the bug still exists. It could be argued that this, in itself, is additional information, since it gives an indication of how widespread and/or persistent the problem is. Those who are perfectly content with a product have few reasons to participate in a bug thread, so those seeking help will tend to mostly read posts by the others who are, or have been, seeking help, if no one has provided a proper solution.

In this comic, multiple people are reporting the problem, as we can tell from their distinctive profile pictures. Most of the visible posts simply state the poster's inclusion in the list of those affected by the bug, either with a one word reply ("Same"), or a shorthand expression of emotion ("{{w|Like button|+1}}. So frustrating."). Some posters, however, do provide somewhat more useful information: existing troubleshooting methods haven't worked for them, with one even providing three links to the specific solutions that they have already unsuccessfully tried.

Although we cannot see the unreadable timestamp information on the posts, one author (the penultimate, using a [[White Hat]] image) makes the observation that the problem has now been ongoing for five years. This is followed by a [[Cueball]]-identified user proposing that this group of like-minded individuals may enjoy meeting up at a {{w|beach house}} in the physical world. Whether this is [[Randall]], or not, his own follow-up comic commentary suggests that bonding over such adversity is as good a reason for friendship as any.

The title text reveals that the meet-up was actually attempted. However, ironically, some of the participants seem to have run into "account issues" when trying to make their reservations, meaning that the website where they tried to rent the beach house wasn't working properly for them. Fortunately that website contained an online support forum like the one in the comic, and six participants from that forum ended up joining the social group. It is unclear whether the meet-up actually ended up occurring, but at least everyone involved now has some new friends.

[[979: Wisdom of the Ancients]] also refers to an online discussion thread about a bug, and [[1305: Undocumented Feature]] also involves a tech support forum which is eventually used only for socializing.

==Transcript==
:[Part of a discussion thread in progress on an online forum is shown. Each comment has the writer's avatar to the left of the text and small illegible text immediately above the text. Part of the first comment's text is cut off at the top.]
:Commenter #1 (icon is a portrait of a stick figure's head with the top half obscured): Same issue here.
:Commenter #2 (icon is a full-body picture of Cueball): I'm having this problem too. None of the posted fixes work.
:Commenter #3 (icon is a thick black stripe going across the icon square from its upper-rightmost corner to its lower-leftmost, with another black stripe in the lower-rightmost corner): Same.
:Commenter #4 (icon is a portrait of Megan's head): +1. So frustrating.
:Commenter #5 (icon is a full-body picture of Hairy left of a horizontal line above an unintelligible shape and a small scribble): I'm still having this. Did you all ever figure out a fix?
:Commenter #6 (icon is a forward-facing bust of Blondie): Same problem as everyone. I tried the steps in the posts here, here, and here. Nothing.
:Commenter #7 (icon is a pure black square with a white circle in the center): Add me to the list.
:Commenter #8 (icon is a portrait of White Hat's head): Same. Ugh. Can't believe this thread is 5 years old now.
:Commenter #9 (icon is a forward-facing portrait of Cueball): Where does everyone live? Do we want to get a beach house for a weekend or something?
:[Caption below the image:]
:At some point, you just have to give up on fixing the bug and embrace the fact that you have dozens of new friends.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Multiple Cueballs]]
[[Category:Internet]]
[[Category:Social interactions]]

2881: Bug Thread

2025-07-18T21:54:46Z

Giraffequeries: Added icon descriptions, may not be detailed enough

{{comic
| number = 2881
| date = January 15, 2024
| title = Bug Thread
| image = bug_thread_2x.png
| imagesize = 317x495px
| noexpand = true
| titletext = After some account issues, we've added 6 new people from the beach house rental website support forum.
}}

==Explanation==

A bug thread is an online discussion about unintended behavior in a program, also known as a {{w|Software bug|bug}}. Bug threads may be found on bug trackers, such as Github or Bugzilla, on technical forums such as StackOverflow, or on general product user forums.

Most bug threads have a rule to only leave a comment if you have something insightful to add,{{Actual citation needed}} such as being able to reproduce how the bug occurs or possible solutions to resolving it. In practice, this rule is often ignored and many threads end up with multiple people simply commenting that the bug still exists. It could be argued that this, in itself, is additional information, since it gives an indication of how widespread and/or persistent the problem is. Those who are perfectly content with a product have few reasons to participate in a bug thread, so those seeking help will tend to mostly read posts by the others who are, or have been, seeking help, if no one has provided a proper solution.

In this comic, multiple people are reporting the problem, as we can tell from their distinctive profile pictures. Most of the visible posts simply state the poster's inclusion in the list of those affected by the bug, either with a one word reply ("Same"), or a shorthand expression of emotion ("{{w|Like button|+1}}. So frustrating."). Some posters, however, do provide somewhat more useful information: existing troubleshooting methods haven't worked for them, with one even providing three links to the specific solutions that they have already unsuccessfully tried.

Although we cannot see the unreadable timestamp information on the posts, one author (the penultimate, using a [[White Hat]] image) makes the observation that the problem has now been ongoing for five years. This is followed by a [[Cueball]]-identified user proposing that this group of like-minded individuals may enjoy meeting up at a {{w|beach house}} in the physical world. Whether this is [[Randall]], or not, his own follow-up comic commentary suggests that bonding over such adversity is as good a reason for friendship as any.

The title text reveals that the meet-up was actually attempted. However, ironically, some of the participants seem to have run into "account issues" when trying to make their reservations, meaning that the website where they tried to rent the beach house wasn't working properly for them. Fortunately that website contained an online support forum like the one in the comic, and six participants from that forum ended up joining the social group. It is unclear whether the meet-up actually ended up occurring, but at least everyone involved now has some new friends.

[[979: Wisdom of the Ancients]] also refers to an online discussion thread about a bug, and [[1305: Undocumented Feature]] also involves a tech support forum which is eventually used only for socializing.

==Transcript==
{{incomplete transcript|add transcripts for commenter icons.}}
:[Part of a discussion thread in progress on an online forum is shown. Each comment has the writer's avatar to the left of the text and small illegible text immediately above the text. Part of the first comment's text is cut off at the top.]
:Commenter #1 (icon is a portrait of a stick figure's head with the top half obscured): Same issue here.
:Commenter #2 (icon is a full-body picture of Cueball): I'm having this problem too. None of the posted fixes work.
:Commenter #3 (icon is a thick black stripe going across the icon square from its upper-rightmost corner to its lower-leftmost, with another black stripe in the lower-rightmost corner): Same.
:Commenter #4 (icon is a portrait of Megan's head): +1. So frustrating.
:Commenter #5 (icon is a full-body picture of Hairy left of a horizontal line above an unintelligible shape and a small scribble): I'm still having this. Did you all ever figure out a fix?
:Commenter #6 (icon is a forward-facing bust of Blondie): Same problem as everyone. I tried the steps in the posts here, here, and here. Nothing.
:Commenter #7 (icon is a pure black square with a white circle in the center): Add me to the list.
:Commenter #8 (icon is a portrait of White Hat's head): Same. Ugh. Can't believe this thread is 5 years old now.
:Commenter #9 (icon is a forward-facing portrait of Cueball): Where does everyone live? Do we want to get a beach house for a weekend or something?
:[Caption below the image:]
:At some point, you just have to give up on fixing the bug and embrace the fact that you have dozens of new friends.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Multiple Cueballs]]
[[Category:Internet]]
[[Category:Social interactions]]

1183: Rose Petals

2025-07-18T21:18:25Z

Giraffequeries: Fixed the transcript, may be wrong? someone check for me

{{comic
| number = 1183
| date = March 8, 2013
| title = Rose Petals
| image = rose petals.png
| titletext = Joke's on you--the Roomba and I had a LOVELY evening.
}}

==Explanation==
This comic strip is playing with romantic movies and gestures used in them. In such movies, one often used romantic gesture is {{tvtropes|FlowersOfRomance|spreading rose petals in the house or apartment}}, making a way towards the bedroom in which a romantic interest/lover is waiting surrounded by roses for a love-making session. The joke is that these petals don't lead from the front door to the bedroom and [[Cueball]]'s lover, but in the opposite direction instead from the bedroom out onto the street. It appears that someone has set up a box of rose petals and an electric fan atop a {{w|Roomba}} (an autonomous robotic vacuum cleaner) as a method of automatically creating such a trail. The title text suggests that despite the other party's intentions of setting this up as a joke to trick Cueball, Cueball ended up having a lovely time with the Roomba.

==Transcript==
:[Cueball enters a room from a door on the left side of the room, to see a line of red rose petals on the floor leading outside the panel and further into the room.]
:[Cueball follows the line of rose petals in the space between two panels.]
:[Cueball continues following the line of rose petals and observes that the trail, snaking around a stack of two books; leads out the front door, down the driveway, and along the sidewalk.]
:[The rose petals lead up to a table fan behind what appears to be a box, presumably filled with rose petals with a small opening in the back. Both are sitting on a Roomba which is mooring down the sidewalk. The fan is on, and is blowing the rose petals out the slit in the back of the box. The contraption, which has the words ROOMBA emblazoned upon the Roomba part of the machine, whirs as it moves along the pavement.]
:Whirrrrrr
:Roomba

{{comic discussion}}
[[Category:Comics with color]]
[[Category:Comics featuring Cueball]]
[[Category:Romance]]
[[Category:Roomba]]

3114: Building a Fire

2025-07-14T18:50:58Z

Giraffequeries: First edit! Removed the incomplete tag for the transcript because it looked fine. Am I doing this right?

{{comic
| number = 3114
| date = July 11, 2025
| title = Building a Fire
| image = building_a_fire_2x.png
| imagesize = 671x311px
| noexpand = true
| titletext = That was quicker than usual! The cabin's sprinkler system often makes it really hard to keep anything lit.
}}

==Explanation==
{{incomplete|This page was created recently. Please add sprinklers to the page so that it doesn’t burn down. Don't remove this notice too soon.}}

[[Megan]] is demonstrating to [[Cueball]] how to build a campfire. She says she's going to use the "log cabin" method, which is a common [https://www.cabinlife.com/articles/the-5-best-campfire-lays-and-how-to-build-them/ method of laying out fuel for a small fire]. The concept is that sticks of wood are placed in layers, with each layer consisting of two sticks placed parallel to one another, with a gap between them. Each subsequent layer is placed perpendicular to the first, so that the sticks bridge the gap in the layer below. This creates an open space in the center in which the tinder, and usually some kindling, is placed and ignited. This method is so named because the walls of {{w|log cabins}} are also built by placing wooden logs in perpendicular layers to enclose a central space, though on a much larger scale.

At first, Megan's build appears similar to a typical {{w|Campfire#Construction_styles|'log cabin' fire lay}}. It becomes unusually detailed when she adds interior walls and miniature furniture in the tiny dwelling, suggesting that she's not just laying out fuel for a fire, but actually going to the trouble of building a miniature log cabin, with all the details and components of a real living space. Things truly take a twist toward the bizarre, however, when she adds plumbing and electrical components to the house. This is not only a complex model, but a structure that apparently includes all the functionality one would expect in a modern dwelling. A fault in the installed wiring then initiates a fire, leading to the promised campfire. Stripped of the complexity, Megan effectively built a campfire which was ignited by electrical heating. Igniting a fire with electricity (either using {{w|electric sparks}} or {{w|Joule_heating|resistive heating}}) is a real method, but not particularly common for campfires.

The joke appears to be that, rather than a traditional (and relatively simple) fire-building method, she builds an entire house in miniature, then simulates a common cause of accidental {{w|structure_fire|house fires}}. This has the same net result as the simpler method: a small and contained fire, but the path to get there was unnecessarily complex. It's also somewhat morbid, as it brings to mind real-life house fires, which are both dangerous and traumatic (tens of thousands of people are killed in house fires every year), which may be the reason Cueball seems so horrified.

The title text continues the joke in that she usually finds that it needs more time for the fire to ignite, due to also installing a {{w|fire sprinkler system}}. Automatic sprinkler systems in buildings are typically to be triggered by fire and spray the area with water, wetting any potential fuel and dousing the fire before it spreads. The joke is that the level of detail in Megan's cabin was not only wildly unnecessary, it's actually actively counterproductive to her supposed purpose of starting a fire. This campfire was only started rapidly because the sprinkler system didn't work properly.

==Transcript==

:[A tent in a field stands in the background to the left of Cueball, who stands behind Megan, who is kneeling and arranging sticks into the first few layers of a small log cabin.]
:Cueball: Can you show me how to build a campfire?
:Megan: Sure! We'll use the log cabin method.
:Megan: First we build a square cabin out of sticks.

:[Cueball now stands to the right of frame, opposite Megan with the cabin between them. The cabin has gotten taller and is becoming better defined. Megan holds a tiny table in one hand and tiny chair in the other.]
:Megan: Next, we'll add interior walls, doors, and some cabin furniture made from twigs.
:Cueball: This is very elaborate.

:[The cabin now has a gable roof and an electrical wire leads from the base of the cabin to a coil of wire in Megan's hand and then off panel to the left. Lightning symbols above the wire indicate the wire is energized and perhaps shorting out.]
:Megan: Now we'll add some rudimentary plumbing and electrical wiring. 50 amps, nothing fancy.
:Cueball: It kind of seems like you're just building a cabin.
:Megan: I just -
:Megan: ...oops.

:[The tiny log cabin is engulfed in flames. Cueball is leaning away from the cabin and holding his hand to shield his face from the heat.]
:Megan: I think my wiring wasn't up to code.
:Cueball: AAAAA!!
:Megan: ... and that's how you build a fire!

{{comic discussion}}<noinclude>
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]