explain xkcd - User contributions [en]

Talk:1559: Driving

2024-03-05T08:25:49Z

162.158.33.141:

They're probably in California, seeing as that's the only place self-driving cars are actually on the road. [[User:Wmss|Wmss]] ([[User talk:Wmss|talk]]) 09:46, 3 August 2015 (UTC)

If there are self-driving cars, what about self-filling cars? So these cars are able to make long distances without the driver's interaction. Maybe he is sleeping. [[User:GeorgDerReisende|GeorgDerReisende]] ([[User talk:GeorgDerReisende|talk]]) 10:47, 3 August 2015 (UTC)
: Yeah, for some reason that does not exist yet -- the self-driving car on the other hand DOES exit and I can see them driving down my street every day [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:07, 4 August 2015 (UTC)

::People have no problem entrust the self-driving cars with their lives, but did you saw how much the petrol costs? Too risky. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 10:26, 4 August 2015 (UTC)

Should've used hitchBOT instead of a rock. [[Special:Contributions/108.162.216.82|108.162.216.82]] 12:46, 3 August 2015 (UTC)

Could this have been a semi-tribute? Showing how some malicious people will abuse technology that is programmed to be too trusting? [[Special:Contributions/108.162.216.138|108.162.216.138]] 20:56, 3 August 2015 (UTC)
: Could you explain with an example [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:07, 4 August 2015 (UTC)

I disagree with the part of the explanation that claims that the comic must take place in the continental US. The title text doesn't specify "exactly two" border crossings; it merely implies that there is more than one. That could be anywhere in mainland (or attached-to-the-mainland-by-bridge) North America, north of the Darien Gap, except for most of Canada (from most of the population centers of Ontario, Google Maps wants to route through Michigan, for a total of three border crossings). [[Special:Contributions/108.162.221.149|108.162.221.149]] 14:18, 3 August 2015 (UTC)
:Correct. It "implies" more than one, but doesn't require it. Only that there be at least one. So they could be in Canada. Essentially anywhere on the continent (or an island connected by bridge to the mainland (e.g., Florida Keys)) north of the Darien Gap but outside Alaska. - Equinox [[Special:Contributions/108.162.238.172|108.162.238.172]] 23:15, 3 August 2015 (UTC)
::I disagree. Randall makes comic in the mainland US and if there is no indication we are outside it is safe to assume they are in the mainland US. And the title text clearly indicated more than one border crossing. You are making it way to complicated. I have corrected accordingly.--[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:02, 4 August 2015 (UTC)

It is likely that the car's owner can locate it via the Internet, via an app and location logic provided by the car's manufacturer. E.g., OnStar. {{unsigned ip|108.162.216.157}}

"At the time of the release of this comic there were no places where these cars could be used privately." That is not true, as there are no restrictions on vehicle use on private property. --[[Special:Contributions/108.162.212.7|108.162.212.7]] 16:35, 3 August 2015 (UTC)
: You are correct, and I have fixed that -- the true statement is that they are not for sale to private individuals [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:03, 4 August 2015 (UTC)

The only US state that both borders Canada and permits self-driving cards is Michigan. Assuming that the logic in self-driving cars prevents them from driving on streets where they are not legal, the conversation would have to take place in that state (but then again, wouldn't the car know that it is not allowed to drive in Alaska?) [[Special:Contributions/162.158.92.64|162.158.92.64]] 19:38, 3 August 2015 (UTC)
:Maybe it's exactly a matter of what knowledge the car has. It ''could'' be linked up to something proprietry, or possibly a Cortana information-engine, to control a virtual "GPS fence", based on current legal and possibly licence-based limits. I'll bet it can be reprogrammed to ignore/extend such limits, though. (Which is why I'm dubious about the idea of 'hard limiting' flying drones from entering restricted airspace. A little hardware/software/firmware hacking should be simple enough for anyone who needs to get around such limits.)
:I can also imagine the following conversation: "How far does your car's self-driving system let you go on automatic?" "I'll ask her..."(/Alaska...) [[Special:Contributions/141.101.98.188|141.101.98.188]] 00:33, 4 August 2015 (UTC)
:Yes the car would know that it was not permitted to drive in Alaska, however that would not prevent it from setting of with that destination in mind assuming that the person would take over control and entering manual driving in places where automatic were not permitted. [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:03, 4 August 2015 (UTC)
::In that case, the "border" in the title text could be a state border... [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 06:13, 4 August 2015 (UTC)
:::But you are still assuming this is the present. If this comic is set in the future they could be anywhere in the US and drive all the way through the country, then through Canada and finally to the destination in Alaska. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:02, 4 August 2015 (UTC)
::::I think you mean North Montana, hasn't been called Canada in years [[Special:Contributions/162.158.255.156|162.158.255.156]] 16:59, 4 August 2015 (UTC)
:::::We always used to call Anchorage "North Seattle." Also, once we casually said "good morning" to a stranger on the street in Inverness (Scotland) and got the instant response "Vancouver!" We said "No, Seattle." The response to that was "Oh, same thing." [[User:Taibhse|Taibhse]] ([[User talk:Taibhse|talk]]) 10:49, 5 August 2015 (UTC)
:There's no reason to assume that the same laws apply in XKCD world, where velociraptors spontaneously attack people who use GOTO. There is also no direct indication that the self-driving car was being operated legally. I feel that trying to pin down the location of this comic is overthinking the matter. [[Special:Contributions/108.162.238.155|108.162.238.155]] 22:37, 5 August 2015 (UTC)
:I agree -- we're wasting valuable time that should be spent arguing that Black Hat is not in fact carrying a sand bag, but rather a large rock!
Many years ago, a major oil company approached an auto research company to come up with both a means to describe as well as coordinates in that system of every fuel filling location on every vehicle. The thought at the time was that the company was seeking to create an automated filling station that could eliminate both the attendant and self-serve. It is only a matter of time. {{unsigned ip|173.245.54.5}}

I can't believe no one is raising the really important question about self-filling cars and/or automatic filling stations: would they be legal on the New Jersey Turnpike? [[Special:Contributions/162.158.255.52|162.158.255.52]] 17:55, 28 September 2015 (UTC)

It should be noted that this comic refers to a driverless car, which is very different from a self-driving car. In short, having a self-driving car means you can set the steering to keep you in your lane, the cruise control to keep you at a safe following distance, maybe even to observe red lights. It can’t make turns or really much of anything without *some* driver interaction. Driverless cars function as the comic describes; the driver enters a destination and the car goes there. It is illegal to test driverless cars on the roads of any state except Michigan. [[Special:Contributions/162.158.62.243|162.158.62.243]] 22:28, 22 February 2018 (UTC)

i thought black hat was holding a pile of hay, not a rock. [[User:Squishmallow fan|Squishmallow fan]] ([[User talk:Squishmallow fan|talk]]) 22:03, 5 February 2024 (UTC)
: I thought it was some dude's head. --[[Special:Contributions/162.158.33.141|162.158.33.141]] 08:25, 5 March 2024 (UTC)

2898: Orbital Argument

2024-02-24T22:41:28Z

162.158.33.141: /* Explanation */

{{comic
| number = 2898
| date = February 23, 2024
| title = Orbital Argument
| image = orbital_argument_2x.png
| imagesize = 448x323px
| noexpand = true
| titletext = "Some people say light is waves, and some say it's particles, so I bet light is some in-between thing that's both wave and particle depending on how you look at it. Am I right?" "YES, BUT YOU SHOULDN'T BE!"
}}

==Explanation==
{{incomplete|Created by a LIGHT WAVE-EARTH BARYCENTER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
In this comic, the person in the middle is using the {{w|Argument to moderation|middle ground fallacy}} to try to make a compromise between the two characters.

[[Cueball]] appears to be asserting a {{w|geocentric}} viewpoint, whilst [[Megan]] adheres to a {{w|heliocentric}} one, an argument that has actually long been settled in the latter's favor. [[White Hat]], however, considers it {{wiktionary|politic#Adjective|politic}} to 'split the difference' and declares his intention to compromise with a 'middle' option, to try to uncritically please both parties. (Though it's probable that he may instead just equally annoy them both!)

By one way of looking at it, it happens that he is also correct. Because two bodies exert equal but opposite gravitational forces on each other (although there is no gravitational force, only warped space-time), each orbits around the average location of the other, and therefore they both orbit a common center. This {{w|Barycenter (astronomy)|barycenter}} is located somewhere between the two bodies, with the two bodies' distances from the barycenter being approximately inversely proportional to their masses. Earth does not orbit the center of the stationary Sun as described by the heliocentric model. However, the Earth-Sun barycenter is only slightly different from the Sun's own true center, still well within the Sun. It is around this which the Sun wobbles, in contrast to the way the Earth orbits around this unequally proportioned midpoint.

The equivalent Jupiter-Sun barycenter, meanwhile, is located just ''above'' the 'surface' of the Sun due to the masses involved being not as different (but still significantly so), and the much greater distance between them. As each of the planets and the Sun are simultaneously orbiting/'being orbited' (and every planet also measurably pulls on every other, etc, even discounting every smaller and/or more distant body in the universe), the combined solar-system's barycenter is a less simply-defined point (that being more likely to be within the Sun, at any given point of time), which can often be considered to more simply average out to "<each planet> orbits the Sun" for most purposes, and Cueball is therefore ''least'' correct, and it would be a false solution to give his worldview an equivalence of validity.

That White Hat has worded his compromise solution in a way that (arguably) encompasses the deeper truth of the barycentric viewpoint is not treated as justifying his mediating approach. It is clearly understood (by someone who seems to understand the complexities, e.g. a {{w|Randall Munroe#NASA|NASA physicist}}) that White Hat's 'successful' conclusion is just accidental. Which is vexatious.

The title text extends the principle of the comic's astronomical viewpoint down to the correspondingly opposing 'quantum world'. For various well-studied reasons, light is often described ''either'' as particles ''or'' as waves. White Hat's approach would be to give both viewpoints equal credit and suggest a compromising middle-ground explanation. In this case, also, he would have the {{w|Wave–particle duality|correct answer}} but, in the continuing view of an increasingly exasperated witness to his chronic {{w|False balance|"half-and-half"ism}}, not through actually correct reasoning.

Another example of the middle ground fallacy was used in [[690: Semicontrolled Demolition]], although in that case the person offering the compromise solution was not portrayed as getting the right answer by accident.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[From left to right, Cueball, White Hat and Megan standing. Cueball and Megan are arguing. Cueball is raising a finger while Megan's arms are outstretched. White Hat stands between them, both hands out in an equivocal gesture.]
:Cueball: The sun orbits the earth!
:Megan: The earth orbits the sun!
:White Hat: When two people disagree, the truth is always somewhere in the middle. Maybe the earth and the sun orbit a common center!

:[Caption below the panel:]
:It's annoying when people are right by accident.
{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Megan]]
[[Category:Astronomy]]
[[Category:Physics]]
[[Category:Logic]]

1453: fMRI

2024-02-10T21:24:27Z

162.158.33.141: Undo revision 334769 by 172.70.126.137 (talk) Don't understand how this is 'unnecessary assumption'. It's a distinct possibility. Don't think original author said *everyone* had them...

{{comic
| number = 1453
| date = November 28, 2014
| title = fMRI
| image = fmri.png
| titletext = They also showed activation in the parts of the brain associated with exposure to dubious study methodology, concern about unremoved piercings, and exasperation with fMRI techs who won't stop talking about Warped Tour.
}}

==Explanation==
{{w|Functional magnetic resonance imaging}} (fMRI), as the name suggests, is an offshoot of the MRI. It shows brain activity, typically while the subject is performing tasks or responding to stimuli. During the test, the subject is laid in a relatively small cylinder inside a big, very loud, machine which produces extremely strong magnetic fields. To prevent damage or injury, the subject must remove all metal objects from their body, including piercings, jewelry, watches, etc.

In the tests shown, the brain activity detected is a direct result of the testing environment itself, and has nothing to do with the simple tasks being performed by the subject. During fMRI participants hear loud noises, are confined in a small space (thus the claustrophobia) and have removed their jewelry. The researcher has mistaken these associated brain activities as effects as being caused by ''performing simple memory tasks'' which the participants have been asked to do and not a direct result of the settings of the test. Thus, the brain areas described by Megan are those associated with taking a functional MRI scan, rather than those associated with the "test" supposedly being carried out. The results being shown are known as {{w|Artifact_(error)|artifacts}}, which are shown later in [[1781: Artifacts]].

In real experiments, reported activity patterns are always a result of subtracting average brain activity from many samples gathered during task from so called ''resting-state'' activity - which is obtained while subjects are not engaged in any task, thus eliminating the effect the setting has on brain activity. Apparently, the researcher in the comic has failed to account for that in the analysis of the data.

The title text raises the more difficult and controversial issues of methodology, saying that the subjects ''also showed activation in the parts of the brain associated with exposure to dubious study methodology''. Here [[Randall]] makes fun of the overly confident, sweeping statements made by some fMRI researchers, often in the press. Of course, fMRI technique requires that the researcher account for several possible sources of errors by, among others, performing proper statistical analyses, multiple comparisons and using proper control groups. These are usually the reasons for {{w|Functional magnetic resonance imaging#Criticism|fMRI criticism}}. See the link for further information, including a famous ironic study of a dead salmon which was shown various pictures of people while fMRI scans were made. The scans could be interpreted as showing meaningful brain activity, unless the {{w|multiple comparisons problem}} was properly addressed. Randall has previously made fun of geographic profiles falling to this trap in comic [[1138: Heatmap|1138]].

The title text then continues with the jewelry issue, now especially the ''concern about unremoved piercings''. In the worst case these could be ripped off by the strong magnetic field. So it could be of some concern - especially when you take into consideration some of the places people may have piercings that are not obvious to the MRI personnel! The final remark about activation regards ''exasperation with fMRI techs who won't stop talking about Warped Tour''. "{{w|Warped Tour}}" refers to a traveling music festival that has been going since 1995, originally as a punk rock festival, but now with a more diverse set of music. Due to the nature of {{w|Moshing|Mosh Pits}}, the loud, cacophonous music, the facial jewelry of concert-goers and the tight quarters of the pit make it similar in description to an MRI.

==Transcript==
:[Megan talking to an unseen audience in front of an fMRI brain scan.]
:Megan: Our fMRI study found that subjects performing simple memory tasks showed activity in the parts of the brain associated with loud noises, claustrophobia, and the removal of jewelry.

{{comic discussion}}
[[Category:Comics with color]]
[[Category:Comics featuring Megan]]
[[Category:Psychology]]
[[Category:Science]]
[[Category:Scientific research]]

2883: Astronaut Guests

2024-01-20T20:40:25Z

162.158.33.141: /* Explanation */ Missed a space. Giving the possible confusion that I meant "covered", re-quoted the slightly made up word referencing the act of 'over'ing (of 'being over').

{{comic
| number = 2883
| date = January 19, 2024
| title = Astronaut Guests
| image = astronaut guests 2x.png
| imagesize = 331x391px
| noexpand = true
| titletext = They didn't bring us a gift, but considering the kinetic energy of a bottle of wine at orbital speed, that's probably for the best.
}}

==Explanation==
{{incomplete|Created by SIX ASTRONAUTS OVER YOUR HEAD RIGHT NOW - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

In this comic, [[Cueball]], [[Megan]], [[Ponytail]], and [[Hairbun]] can all be seen eating dinner together. Presumably, Ponytail and Hairbun were invited over for dinner, as, to impress them, [[Cueball]] misleadingly claims that they previously "had six {{w|astronauts}} over for dinner." Normally, this would be interpreted as the astronauts being friends with the hosts (which confers social prestige), going inside their house, and eating. As it turns out, the astronauts actually only briefly passed overhead while in {{w|orbit}}, and, by chance, this happened during dinnertime. This is a pun on the word "over", as the personnel of the {{w|International Space Station}} are overhead when it passes above you— yet they did not go "over ''to'' someone's house" in the sense that English speakers would usually assume.

Cueball may also be considering the property lines to extend up indefinitely (just like in "What If?" article "{{what if|161|Star Ownership}}"), causing the astronauts to technically be at their house despite being hundreds of miles away, vertically. The astronauts in question were presumably occupying the International Space Station, which has an orbital period of between 90 and 93 minutes (depending on its altitude) or 5400 to 5580 seconds.[https://eol.jsc.nasa.gov/Tools/orbitTutorial.htm] If the astronauts were "over" for 7½ milliseconds, that would be somewhere between 1.34x10⁻⁶ and 1.39x10⁻⁶ of an orbit. Earth's circumference (at the equator) being approximately 40,000 kilometers (24,850 miles), the station was apparently "over" for a ground distance of between 53.9 m and 55.7 m (177 to 183 feet). That would imply quite a large property, but may also take into account the locations of the astronauts within the ISS, which is 109 m (356 feet) long (before considering the much smaller [[1276: Angular Size|angular size]] with respect to the ground).

The caption makes Cueball's statement even less impressive, alleging that statements like it are correct in a lot of place. This would make it not even interesting as a {{w|coincidence}}. Though it can only happen for latitudes of less than 51.64° north or south, which is as far as the orbital inclination of the ISS takes it, leaving almost 21.6% of the Earth's surface never directly 'over'ed.

The title text suggests that Cueball didn't want a gift (a bottle of wine) from the astronauts. The kinetic energy of a 1.2 kg (full) bottle of wine traveling at the linear velocity of the International Space Station (8000 m/s) is on the order of 40,000 kilojoules (kJ). For comparison, the kinetic energy of a [https://en.wikipedia.org/wiki/Yoshinobu_Yamamoto Yamamoto Yoshinobu] fastball is around 0.16 kJ. That bottle would be hard to keep on the table, and would likely do damage to people or things that tried to keep it there.

This comic was posted the same day as the American release of a film set on the ISS (conveniently named ''{{w|I.S.S. (film)|I.S.S.}}'').

==Transcript==
{{incomplete transcript}}
:[Cueball, Megan, Ponytail, and Hairbun are eating around a table. Cueball is leaning on the back of his chair and has his palm out.]
:Cueball: We don't have houseguests often, but we once had six astronauts over for dinner.
:Hairbun: Oh, wow!
:Cueball (muttering): ''…for 7½ milliseconds in mid-August 2012.''

:[Caption below the panel:]
:If you spend enough time looking at orbital records and property lines, you can make this claim in a lot of places.

{{comic discussion}}
[[Category: Comics featuring Cueball]]
[[Category: Comics featuring Ponytail]]
[[Category: Comics featuring Megan]]
[[Category: Comics featuring Hairbun]]
[[Category: Space]]

Talk:2872: Hydrothermal Vents

2023-12-26T17:57:58Z

162.158.33.141:

Current text: "... but could theoretically repopulate the surface if there were ever extenctions in the real world, as there have been in prior times." Should extenctions be extinctions?
[[Special:Contributions/172.69.195.176|172.69.195.176]] 12:01, 26 December 2023 (UTC)
:I was the one who (somehow mis)typed that, and indeed it should. If it hasn't been corrected by the time I get there, I'll do it. (Related, or not, but my on-screen keyboard appears to have updated over the last day or so. I had to reset it back to how I like it (no drag-to-type, no 'suggestions' bar above, remove the emoji button) and I'm sure it's also resized vertically, meaning I may mis-hit 'keys' on different rows, but not sure how I got 'e' instead of 'i'. Put it down to an inexicable Thinko, perhaps?) Also, I might change to make clear that (e.g.) hydrothermic crustacea might (re)redevelop 'regular' phototropic versions (or those atuned to photosynthesis-rooted food webs, or something), instead of being chemosynthesis-rooted. But that could be too difficult to summarise.
:...darnit, where's the tilde on this changed OSK? (Ah, there it is. Looks like they added a 'handy' numberpad setting, which I need to switch away from to get where the ~ still resides!) Yet another bothersome 'improvement' that I'll have to see if I can deal withn in the settings... Sheesh... [[Special:Contributions/172.69.194.225|172.69.194.225]] 14:18, 26 December 2023 (UTC)

Regarding the ethology of the benthic species of ''Rangifer tarandus'', the May-Marks natigational hypothesis has now been largely supplanted by the idea of the "angler deer", in which the low-frequency luminescence around the covering of the turbinate bones is used used as a lure, attracting abyssopelagic subspecies of ''Daucus carota'' that would ordinarily avoid regions of such extreme temperature. [[User:Yorkshire Pudding|Yorkshire Pudding]] ([[User talk:Yorkshire Pudding|talk]]) 12:23, 26 December 2023 (UTC)

This may well be the most dark Christmas comic ever in the history of xkcd! And not even really funny. Don't get my wrong I can still be amused but find it a bit out of the ordinary for saying Merry Christmas ;-) --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 13:36, 26 December 2023 (UTC)
:Oh, don't worry, this only traps ''benthic'' santas. As you'll have noticed, your own Julemanden has remained unaffected... As you can tell by the lack of charboiled reindeer ''or'' nisser, just beyond the 'chimneys' themselves. [[Special:Contributions/172.69.194.225|172.69.194.225]] 14:18, 26 December 2023 (UTC)

The link to an article explaining ''Buffy the Vampire Slayer's'' slayer replacement system, is humorous & mostly apropos, but I feel that a link to ''The Santa Clause'' would be much more directly relevant?

The ecology and behavior of "benthic santas" (putative taxon Abyssosanta bathytroglodyta) may have been [ahem] profoundly different from the extant species. The clues are few, but they support the hypothesis that A. bathytroglodyta sought out chimney-like structures and other crevices for shelter and food, to which they were perhaps guided by a symbiosis with Rangiferpisces rubrum, the red-antlered reindeerfish. Predation pressure from hydrothermal vent chimney mimics (Nigroventus abyssosantavorus) would have driven A. bathytroglodyta to the surface. In a possible analogy, the Atlantic clawed lobster, Homarus americanus, initially a deep-water species, was driven to the intertidal zone by predation from Gadus gadus (cod) and other large fish - only to be confronted with intolerable predation pressure from humans, to which they eventually adapted. By this model, the modern Santa (Santa donator) evolved from its precursor species under strong human selection pressure. At least S. donator was, from its precursor's traits, preadapted for a high-pressure existence, and for the cold and dark of the Arctic. [[Special:Contributions/172.70.214.80|172.70.214.80]] 16:51, 26 December 2023 (UTC)
:<applause />[[Special:Contributions/162.158.33.141|162.158.33.141]] 17:57, 26 December 2023 (UTC)

175: Automatic Doors

2023-12-24T21:39:32Z

162.158.33.141: /* Explanation */ typo

{{comic
| number = 175
| date = October 25, 2006
| title = Automatic Doors
| image = automatic_doors.png
| titletext = I hope no automatic doors I know read this. I would be so embarrassed.
}}

==Explanation==
[[Cueball]] has an uneasy suspicion that the automatic doors may have feelings, possibly due to their apparent sentience. This assigning of human characteristics to non-human things such as the doors is called {{w|anthropomorphism}}. Cueball extends the premise that the doors have feelings to those feelings being hurt by his not entering the opened doors. This is analogous to the social faux pas of ignoring someone who has waved to you, or purposefully failing to acknowledge someone who is trying to get your attention.

The anthropomorphized doors are much like those in the starship Heart of Gold in Douglas Adams' ''{{w|Hitchhiker's Guide to the Galaxy}}''. In the story, the characters find a brochure describing the ship, which states that "All the doors in this spaceship have a cheerful and sunny disposition. It is their pleasure to open for you, and their satisfaction to close again with the knowledge of a job well done." Such doors would not be given the "satisfaction" of the "knowledge of a job well done" if the figure passes close enough to trigger the doors, but does not actually go through them.

In the title text, it is revealed that Cueball has made the acquaintance of a number of automatic doors and possibly hung out with them only because he doesn't want to hurt their feelings. His being embarrassed about hurting the feelings of any automatic doors who happen to read the comic and thus find out that what they thought was a genuine friendship was only Cueball trying not to hurt their feelings, in fact should more likely be embarrassment over making friends with mechanical doors who he believes have feeling that can be hurt in the first place.{{Citation needed}}

==Transcript==
:When I walk past an automatic door and it opens for me, I worry that if I don't go in I'll hurt its feelings.
:[Automatic door whirrs open.]
:''whirrrr''
:Cueball: Oh, um, I'm sorry, I was just... um... I guess I can hang out for a bit.

{{comic discussion}}
[[Category:Comics featuring Cueball]]

2871: Definitely

2023-12-23T18:05:33Z

162.158.33.141: /* Explanation */

{{comic
| number = 2871
| date = December 22, 2023
| title = Definitely
| image = definitely_2x.png
| imagesize = 463x461px
| noexpand = true
| titletext = A really mean prank you can play on someone who's picky about words is to add a 'definitely->definitively' autocorrect rule to their keyboard.
}}

==Explanation==
{{incomplete|Created by a DEFIANT DEFINITION - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

The word "''{{wiktionary|definitely}}''" is commonly {{wiktionary|misspelt}}, perhaps because it may be voiced as "def-in-ATE-ly", or with other vowels/emphisis. (The wiktionary link mentions three, /ˈdɛf.ɪ.nɪt.li/, /ˈdɛf.ə.nɪt.li/, /ˈdɛf.nɪt.li/, which are just some of the differences you might encounter.) Remembering that it ultimately has a common root with "finite", and thus has the two 'i's, does not help if you also/instead perhaps link it in your head to "''define''" (which might erroneously lead to "''defin'''e'''tely''") and not "definition").

The comic gives twelve 'words' that the subtitle claims are all real, and gives their definitions, whereas in reality only the first (the definitely definitive spelling of "''definitely''" and the last (defying the trend by being the actual word "''{{wiktionary|defiantly}}''") are indeed so.

The first three alternate 'words' listed do have Wiktionary entries that indicate they are common mis-spellings of the first, and the last has a secondary 'meaning' of possibly being such an error, but (as of the publication of this comic/edit) the words "''defenitely''", "''defintely''", "''definetely''" [defined as "{{w|Definitely, Maybe}}"], "''definantly''", "''defanitely''", "''defineatly''" and "''definitly''" are ''so'' wrong that they don't even have a corrective article created for them. Some of them don't even look like they'd even be sufficiently homophonic substitutes, though the actions of accent and dialect may indeed be capable of creating compatible (mis)elocutions for each.

The title text adds to the word confusion by suggesting the real word "''{{wiktionary|definitively}}''" (for which Wiktionary has a 'See also' link to "definitely") be made to be used (against the will of a word-wise individual) as a substitution for the original definitely definitive spelling. In certain contexts it even fulfils the same basic sense as the original and so may survive proofreading by a third party. Or even the author glancing through their own work, and the brain not twigging the increased number of riser-rich characters but mentally voicing the intended word anyway... Even if it is noticed, it may be considered more a "''{{wiktionary|thinko}}''" than a "''{{wiktionary|typo}}''" as it keeps happening, at least until the afflicted typist starts to pay close and distracting attention to their output.

==Transcript==
{{incomplete transcript|Do not delete this tag too soon.}}

:Word   Meaning

:Definitely - Definitely
:Definetly - ''Almost'' definitely
:Definately - Probably
:Definatly - Probably not
:Defenitely - Not telling (it's a surprise)
:Defintely - Per the prophecy
:Definetely - Definitely, maybe
:Definantly - To be decided by coin toss
:Defanitely - In one universe out of 14 million
:Defineatly - Only the gods know
:Definitly - Unless someone cute shows up
:Defiantly - Defiantly

:[Caption below the panel:]
:People think the word "definitely" is often misspelled, but it's actually just several words with different meanings.

{{comic discussion}}

[[Category:Language]]

2865: The Wrong Stuff

2023-12-14T04:30:11Z

162.158.33.141:

{{comic
| number = 2865
| date = December 8, 2023
| title = The Wrong Stuff
| image = the_wrong_stuff_2x.png
| imagesize = 351x513px
| noexpand = true
| titletext = The phantom found Edward Everett Hale a century too early; by the time we invented satellites, the specifics of his 'brick moon' proposal were dismissed as science fiction.
}}

==Explanation==
{{incomplete|Created by a TRAIN MADE OF 1977 SOVIET URANIUM - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
Multiple times in history, there have been incidents where companies, governments, and engineers have proposed or developed plans for large vehicles composed of unconventional materials. One example is {{w|Project Habakkuk}} (mentioned in the comic), an aircraft carrier which was to be composed of pykrete, a mixture of wood pulp and ice. The comic imagines that all of these proposals are linked together by a single "Material Phantom," a ghost which haunts engineers and convinces them to design giant vehicles made of impractical materials.

The three "wrong material vehicles" mentioned in the comic are:

*{{w|The Spruce Goose}} - The largest {{w|flying boat}} ever made, in spite of its name, almost entirely out of {{w|birch}} wood. Most modern planes of that era were being constructed out of aluminum or some other metal/alloy. Due to wartime restrictions on aluminum usage, the use of birch wood was the next best option. The development of the aircraft was highly troubled due to various factors (including building in wood at an unprecedented scale), and the designers were accused of war-profiteering with an impossible design. The plane did make a single 26-second flight in 1947, well after the end of the war, but proving the concept was possible. The plane is currently on display at the {{w|Evergreen Aviation & Space Museum}} in {{w|McMinnville, Oregon}}, {{w|United States}}. Other wooden aircraft of that era, such as the {{w|De_Havilland_Mosquito|De Havilland Mosquito}}, were highly successful. Many early planes made use of wood in their construction, and the skills and knowledge to build an airframe of that kind were still readily available in that era, in a way that they might not be today.
*{{w|Project Habakkuk}} - A proposed aircraft carrier whose hull was to be made out of pykrete (a mixture of wood pulp and ice). Although the project excited great enthusiasm from Churchill, it quickly became clear that Pykrete did not scale well as a material, needing to be super-cooled to prevent {{w|Creep_(deformation)}}, requiring a massive cooling system causing expense and engineering challenges to mount until it was concluded that it would cheaper to build traditional steel-alloy hulls, from which ships continue to be built today, given that large quantities of metal were pulled in to prevent the ship from warping under its own mass via extra cooling and structural support. There were also now airfields available to use in various Atlantic islands that could close the air-gap in coverage without having to (effectively) build their own floating island from scratch.
*{{w|Trojan Horse}} - A mythological, giant wooden horse, supposedly used by {{w|Ancient Greece|the Greeks}} to invade the city of {{w|Troy}}. Actual horses are composed, like any other animal, out of meat, bone, and other tissues and bodily fluids, rather than wood.{{citation needed}} In addition, the interior of the Trojan Horse was composed of Greek warriors rather than horse innards.

The title text references 19th-century author {{w|Edward Everett Hale|Edward Everett Hale}} and his science fiction novella ''{{w|The Brick Moon}},'' the earliest known depiction of an artificial satellite and a scientifically-accurate GPS system in fiction. The satellite was made from brick as it is a refractory ceramic material capable of dealing with high heats. The novella is, of course, just a sci-fi story, but the title text states that Hale was actually approached by the Material Phantom, and the novella was a serious proposal for a moon made out of bricks.

The title "the Wrong Stuff" may be a play on {{w|The Right Stuff}}, a book/movie/TV series about the pilots engaged in U.S. postwar research with experimental rocket-powered, high-speed aircraft and the astronauts of {{w|Project Mercury}}. In that title, "the right stuff" refers to the figurative material that these men were made of which gave them the bravery to embark on these missions.

==Trivia==
This comic was uploaded with the "the" in "the Wrong Stuff" being entirely lowercase, breaking the normal title case used for XKCD comic titles. Possibly another word was initially intended to come before "the", in which case lowercasing "the" would be correct. xkcd displays lowercase letters in titles with {{w|small caps}}, making the lowercase "the" less obvious than it is in the true lowercase used on explainxkcd.

However, it's worth noting that the comic title has since been changed to "The Wrong Stuff," with "the" capitalized as per standard title case.

Every September, Adult Fans of Lego who like spaceships have a month long build event called SHIPtember (SHIP stands for Seriously Huge Investment in Parts) where spaceships are actually built out of bricks: Lego bricks!

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[A ghost is approaching Cueball in a workshop. They are surrounded by shop equipment, such as a table with a press on it, and a small pile of what appears to be lumber. Cueball is backing away from the ghost, holding his hands up defensively.]
:Ghost: oooOOOOOOoooo
:[The "ooooo"s of the ghost are written in wavy letters of varying sizes]
:Ghost: ''Build a spaceship out of bricks!''
:Ghost: oooooOOOOOOOOoo
:Cueball: No! Go away!

:[Caption below the panel:]
:The Spruce Goose, the Project Habakkuk Ice Ship, and the Trojan Horse were all work of the Material Phantom, a ghost that wanders the Earth convincing engineers to make giant vehicles out of the wrong stuff.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Engineering]]

2865: The Wrong Stuff

2023-12-14T04:29:36Z

162.158.33.141: copy edit

{{comic
| number = 2865
| date = December 8, 2023
| title = The Wrong Stuff
| image = the_wrong_stuff_2x.png
| imagesize = 351x513px
| noexpand = true
| titletext = The phantom found Edward Everett Hale a century too early; by the time we invented satellites, the specifics of his 'brick moon' proposal were dismissed as science fiction.
}}

==Explanation==
{{incomplete|Created by a TRAIN MADE OF 1977 SOVIET URANIUM - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
Multiple times in history, there have been incidents where companies, governments, and engineers have proposed or developed plans for large vehicles composed of unconventional materials. One example is {{w|Project Habakkuk}} (mentioned in the comic), an aircraft carrier which was to be composed of pykrete, a mixture of wood pulp and ice. The comic imagines that all of these proposals are linked together by a single "Material Phantom," a ghost which haunts engineers and convinces them to design giant vehicles made of impractical materials.

The three "wrong material vehicles" mentioned in the comic are:

*{{w|The Spruce Goose}} - The largest {{w|flying boat}} ever made, in spite of its name, almost entirely out of {{w|birch}} wood. Most modern planes of that era were being constructed out of aluminum or some other metal/alloy. Due to wartime restrictions on aluminum usage, the use of birch wood was the next best option. The development of the aircraft was highly troubled due to various factors (including building in wood at an unprecedented scale), and the designers were accused of war-profiteering with an impossible design. The plane did make a single 26-second flight in 1947, well after the end of the war, but proving the concept was possible. The plane is currently on display at the {{w|Evergreen Aviation & Space Museum}} in {{w|McMinnville, Oregon}}, {{w|United States}}. Other wooden aircraft of that era, such as the {{w|De_Havilland_Mosquito|De Havilland Mosquito}}, were highly successful. Many early planes made use of wood in their construction, and the skills and knowledge to build an airframe of that kind were still readily available in that era, in a way that they might not be today.
*{{w|Project Habakkuk}} - A proposed aircraft carrier whose hull was to be made out of pykrete (a mixture of wood pulp and ice). Although the project excited great enthusiasm from Churchill, it quickly became clear that Pykrete did not scale well as a material, needing to be super-cooled to prevent {w|Creep_(deformation)}, requiring a massive cooling system causing expense and engineering challenges to mount until it was concluded that it would cheaper to build traditional steel-alloy hulls, from which ships continue to be built today, given that large quantities of metal were pulled in to prevent the ship from warping under its own mass via extra cooling and structural support. There were also now airfields available to use in various Atlantic islands that could close the air-gap in coverage without having to (effectively) build their own floating island from scratch.
*{{w|Trojan Horse}} - A mythological, giant wooden horse, supposedly used by {{w|Ancient Greece|the Greeks}} to invade the city of {{w|Troy}}. Actual horses are composed, like any other animal, out of meat, bone, and other tissues and bodily fluids, rather than wood.{{citation needed}} In addition, the interior of the Trojan Horse was composed of Greek warriors rather than horse innards.

The title text references 19th-century author {{w|Edward Everett Hale|Edward Everett Hale}} and his science fiction novella ''{{w|The Brick Moon}},'' the earliest known depiction of an artificial satellite and a scientifically-accurate GPS system in fiction. The satellite was made from brick as it is a refractory ceramic material capable of dealing with high heats. The novella is, of course, just a sci-fi story, but the title text states that Hale was actually approached by the Material Phantom, and the novella was a serious proposal for a moon made out of bricks.

The title "the Wrong Stuff" may be a play on {{w|The Right Stuff}}, a book/movie/TV series about the pilots engaged in U.S. postwar research with experimental rocket-powered, high-speed aircraft and the astronauts of {{w|Project Mercury}}. In that title, "the right stuff" refers to the figurative material that these men were made of which gave them the bravery to embark on these missions.

==Trivia==
This comic was uploaded with the "the" in "the Wrong Stuff" being entirely lowercase, breaking the normal title case used for XKCD comic titles. Possibly another word was initially intended to come before "the", in which case lowercasing "the" would be correct. xkcd displays lowercase letters in titles with {{w|small caps}}, making the lowercase "the" less obvious than it is in the true lowercase used on explainxkcd.

However, it's worth noting that the comic title has since been changed to "The Wrong Stuff," with "the" capitalized as per standard title case.

Every September, Adult Fans of Lego who like spaceships have a month long build event called SHIPtember (SHIP stands for Seriously Huge Investment in Parts) where spaceships are actually built out of bricks: Lego bricks!

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[A ghost is approaching Cueball in a workshop. They are surrounded by shop equipment, such as a table with a press on it, and a small pile of what appears to be lumber. Cueball is backing away from the ghost, holding his hands up defensively.]
:Ghost: oooOOOOOOoooo
:[The "ooooo"s of the ghost are written in wavy letters of varying sizes]
:Ghost: ''Build a spaceship out of bricks!''
:Ghost: oooooOOOOOOOOoo
:Cueball: No! Go away!

:[Caption below the panel:]
:The Spruce Goose, the Project Habakkuk Ice Ship, and the Trojan Horse were all work of the Material Phantom, a ghost that wanders the Earth convincing engineers to make giant vehicles out of the wrong stuff.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Engineering]]

Talk:233: A New CAPTCHA Approach

2023-12-13T13:13:40Z

162.158.33.141:

Both of those fail against autistic people (and people who have diseases similar to autism, one example being FG syndrome). [[User:Greyson|Greyson]] ([[User talk:Greyson|talk]]) 17:49, 24 January 2014 (UTC)
:Or, y'know, people who haven't seen the movie/episode. --[[User:Alex|Alex]] ([[User talk:Alex|talk]]) 21:09, 28 April 2014 (UTC)
:Not really. It depends more on what type of person they are, less on what conditions they have. [[User:Beanie|Beanie]] ([[User talk:Beanie|talk]]) 10:46, 19 March 2021 (UTC)

Not exactly, because kids with autistic-spectrum disorders can be more sensitive. The only pop-culture example I can think of is Sheldon Cooper's sadness when he learned of Professor Proton's passing. {{unsigned ip|108.162.249.240}}
:Can confirm. [[User:Beanie|Beanie]] ([[User talk:Beanie|talk]]) 10:46, 19 March 2021 (UTC)

A better example would be the dog in I Am Legend. Also, the text for the question and for the answers would both have to be distorted slightly. [[Special:Contributions/173.245.50.87|173.245.50.87]] 06:02, 11 September 2015 (UTC)

The obvious alusion is Deckard's empathy test on Leon in Blade Runner to determine whether he is human. {{unsigned ip|108.162.229.30}}
:You know it was from Do Androids Dream of Electric Sheep by Phillip K. Dick first, right? The movie was based on that. {{unsigned ip|108.162.218.166}}

I don't remember crying to that scene when I was younger. I do- I mean, did cry when Optimus Prime died in the '87 Transformers movie though. -Pennpenn [[Special:Contributions/108.162.249.225|108.162.249.225]] 04:25, 26 January 2015 (UTC)

The funniest thing is the Infosphere does use Fry's dog as a captcha like this. Hutc {{unsigned ip|141.101.98.193}}

This seems to be an allusion to the Voight-Kampff test in the movie Blade Runner. The test is used to distinguish humans from 'Replicas' (artificial humans) by asking questions designed to elicit an emotional response, and then monitoring biological metrics in the respondent. The idea being that replicas would be unable to maintain a convincing fakery against such a systematized methodology. [[User:Danshoham|Mountain Hikes]] ([[User talk:Danshoham|talk]]) 01:55, 25 September 2015 (UTC)
:It's "Replicants", not "Replicas". [[User:The Cat Lady|--The Cat Lady]] ([[User talk:The Cat Lady|talk]]) 10:36, 13 August 2021 (UTC)

Am I the only one who didn't cry with that episode with Fry's dog? I mean it was sad but I didn't cry. On top of that one of the movies makes that scene a LOT less sad.

I suppose I'm just a cold, heartless satellite. Fry's dog may work on spambots but not satellites. [[User:International Space Station|International Space Station]] ([[User talk:International Space Station|talk]]) 15:35, 22 April 2016 (UTC)

I never really cry in movies because I know that they are fake. most of the time.

=== Captcha ===
Another captcha approach is making use of the [[Halting Problem]] (Will this program halt?), as computers can't solve it, while humans can find a pattern. [[User:ColorfulGalaxy|ColorfulGalaxy]] ([[User talk:ColorfulGalaxy|talk]]) 20:39, 11 December 2022 (UTC)
:...or die trying! [[Special:Contributions/172.70.85.174|172.70.85.174]] 20:58, 12 December 2022 (UTC)

i didn't cry because when i saw it it didn't relate in any way to something that happened to me (now it does D:) [[User:An user who has no account yet|An user who has no account yet]] ([[User talk:An user who has no account yet|talk]]) 20:37, 7 September 2023 (UTC)
:>comforting headpats --[[Special:Contributions/162.158.33.141|162.158.33.141]] 13:13, 13 December 2023 (UTC)