explain xkcd - User contributions [en]

Talk:2200: Unreachable State

2019-09-11T07:51:10Z

Kventin: don't be cute

When I tried to go here originally, it was unreachable. [[Special:Contributions/162.158.107.61|162.158.107.61]] 03:54, 11 September 2019 (UTC)

nothing about the comic suggests a website. it looks more like the error message of a program. also, i don't think CB is typing it, just reading. [[Special:Contributions/172.68.50.124|172.68.50.124]] 06:20, 11 September 2019 (UTC)

== "Can't happen" ==

This comic is not about "a problem that the programmers did not anticipate", but rather a situation that the programmer rules out as impossible, which is technically called "Can't happen" or "Impossible Error" in the hacker/programmer's jargon. See http://catb.org/jargon/html/C/can-t-happen.html

For example:
<source lang=php>
for ($i=1;$i<=5;++$i) {echo $i." - ";}
if ($i<10) {echo "Bye!";} else {echo "Can't happen!";}
</source>

[[User:ElfQrin|ElfQrin]] ([[User talk:ElfQrin|talk]]) 07:14, 11 September 2019 (UTC)

Also it helps not to be too cute even with impossible error messages. A colleague left a message along the lines of <q>Application rubbish bin has broken.</q> once. Cue a somewhat perplexed user call several years later…
<blockquote>
“Scientists have calculated that the chances of something so patently absurd actually existing are millions to one.
But magicians have calculated that million-to-one chances crop up nine times out of ten.”

― Terry Pratchett, Mort
</blockquote>

--[[User:Kventin|Kventin]] ([[User talk:Kventin|talk]]) 07:51, 11 September 2019 (UTC)

Talk:2193: Well-Ordering Principle

2019-08-28T06:13:49Z

Kventin: theworstmcfly.com

Still a "trap": POOF, you're now the worst McFly cosplayer; here's a mirror.
:She asked about people who 'tried' to dress as Marty McFly. So unless Megan has ever tried to dress as him, I don't think she can be the answer.[[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 00:10, 24 August 2019 (UTC)
::_Technically_, Megan never used the formal "I wish" construction: she had "my wish is" and "just show me." Since the genie didn't immediately grant it in response to "my wish is," either (1) it's not possible (see other folks' comments below), (2) like Alex Trebec, he requires the proper format, or (3) we can assume that he'll respond to a direct order ... in which case, Megan will become a McFly cosplayer in a subsequent panel. :p
:Considering that wishing for any of the genie's suggestions would make her a wanted criminal that stole a billion dollars, a housefly in a room full of irritable people, or a genie trapped in a lamp for all eternity, this is hardly a terrible fate. [[Special:Contributions/172.68.65.66|172.68.65.66]] 14:04, 25 August 2019 (UTC)
:: Beware. The worst Marty McFly may be truly terrible. Or it could be a little kid in a costume they made out of craft paper and colored in crayon, terrible but adorable... but it could involve (1) real lightning, (2) real plutonium, (3) the band McFly, (4) actually a dog in costume, (5) actually a fly in costume, (6) Jeff Goldblum from "The Fly" i.e. fly head not Jeff Goldblum head - in costume, (7) Cthulhu - in costume. (The last and worst trick-or-treat you'll ever see; he would qualify.) rja.carnegie@gmail.com [[Special:Contributions/162.158.158.209|162.158.158.209]] 14:36, 26 August 2019 (UTC)
:She only wished to see "their costume". So the genie could trap her by only showing the costume, without letting her know how it looked on the wearer. In fact, the genie can also opt to ignore the "singular they" madness and bury her in a pile of costumes (of everyone who ever wore one for Halloween). [[Special:Contributions/198.41.231.135|198.41.231.135]] 16:50, 26 August 2019 (UTC)

*Are* costumes well-ordered? Even leaving aside the subjectivity of any ranking, there are several different criteria which could be used, and many ways of combining them. (What if the costume which looked least like Marty wasn't the ugliest, nor the one showing least effort?) — Also, may be worth qualifying the explanation of Halloween by mentioning the USA; some other countries don't celebrate it, and of those that do, not all do trick-or-treating or dressing-up &c. [[User:Gidds|Gidds]] ([[User talk:Gidds|talk]]) 00:23, 24 August 2019 (UTC)

::Saying there are different criteria kind of overlaps with saying the ranking is subjective. But far worse, even individual preferences are preorders aka quasiorders, which absolutely does mean that there may not be a worst, or even a set of costumes tied for worst. However, the fact that you can always find someone (e.g. on Amazon Mechanical Turk, or off the street, or on a wiki somewhere) to give you another opinion means that well-foundedness can be rescued with their {{w|mean opinion score}}. I wonder if the genie is powerful enough to know the asymptotic MOS ranking right away, or if it will have to wait for enough Amazon Mechanical Turk HITs to be completed. Given that there must have been at least hundreds of thousands of consumes so far, that could take quite a long time to achieve p<0.05. [[Special:Contributions/172.69.22.248|172.69.22.248]] 04:00, 24 August 2019 (UTC)
::I've spent way too much time on this, but the more I do, the more I think Randall is trying to say something about the simulation hypothesis, related to the theme on [https://www.youtube.com/watch?v=th5uJNB7VU8 ''Watch Room''] (warning: somewhat creepy but otherwise ok sci-fi short.) [[Special:Contributions/172.69.22.134|172.69.22.134]] 12:32, 24 August 2019 (UTC)

I hope this Munroe lowkey challenging the internet, that we might actually celebrate our infamous king (or girl marty queen) of crappy costume. --[[Special:Contributions/162.158.58.219|162.158.58.219]] 00:37, 24 August 2019 (UTC)

The "worst McFly" and "even" sounds like there should be a math pun in there somewhere, but I don't see it. [[Special:Contributions/172.69.63.11|172.69.63.11]] 01:36, 24 August 2019 (UTC)

"It's been over 30 years since Back to the Future came out." That makes me feel old. Isn't that something that Munroe does regularly? Should that be mentioned in the explanation? [[Special:Contributions/162.158.214.88|162.158.214.88]] 10:42, 24 August 2019 (UTC)
:Yes, I am sure there have been at least two comics where the often surprising ages of things formed a central part of the theme, but I can't remember enough about them to find them. Anyone? [[Special:Contributions/162.158.255.82|162.158.255.82]] 11:55, 24 August 2019 (UTC)
::Just see [[:Category:Comics to make one feel old]] :-). --[[User:DaB.|DaB.]] ([[User talk:DaB.|talk]]) 12:29, 24 August 2019 (UTC)
:::Thanks {{done}} [[Special:Contributions/172.69.22.134|172.69.22.134]] 12:38, 24 August 2019 (UTC)

"The real Worst McFly is probably lost to time" is also a pun regarding the fact that ''Back to the Future'' is a time-travel story.--[[User:MCBastos|MCBastos]] ([[User talk:MCBastos|talk]]) 17:20, 24 August 2019 (UTC)

I wonder if this could be trap from Megan - even unintended one: in some stories, the Genie could get into problems if he CANT fulfill the wish ... -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 22:07, 24 August 2019 (UTC)

Even if "preference" is a total order (i.e. connex and anti-symmetric, I think both of these are debatable) it isn't necessarily a well order, however, since the set of costumes is finite, there would still be a "worst" one. [[User:Probably not Douglas Hofstadter|Probably not Douglas Hofstadter]] ([[User talk:Probably not Douglas Hofstadter|talk]]) 03:17, 25 August 2019 (UTC)

:It's not a total preorder unless you don't let people have "no opinion" about some pairs, which is an acceptable constraint for preferences based on established objective criteria, but not something so subjective like quality of fashion. In practice, a lot of people are going to have least favorites between which they don't care. Surveys of subjective preferences almost always allow people to say that they don't have opinions or are not sure. Even in technically objective measures, like short- versus long-term bond yield curves, you can sometimes prove that people objectively should have certain preferences upon which they are clearly not acting. [[Special:Contributions/172.68.189.19|172.68.189.19]] 07:40, 25 August 2019 (UTC)

Sounds like a trap -- for the genie. Keep it busy so that it can't inflict "wishes" on others. Much more subtle than "find the last digit of pi", but possibly still a "halting problem" that can never be fully solved.

Actually, this wish is simply if not easily fulfilled, and it may indeed be a trap for Megan. Simply show her every Marty McFly costume ever worn. At some point she would have to have seen the worst, no matter how worst was determined. Depending upon the method, this could take a very long time. [[Special:Contributions/108.162.246.239|108.162.246.239]] 00:48, 27 August 2019 (UTC)
:Good point; added. [[Special:Contributions/172.68.142.83|172.68.142.83]] 06:34, 27 August 2019 (UTC)

Knowing this community and knowing the wetriffs.com story, I'm already looking forward to this year's Halloween
[[User:Kventin|Kventin]] ([[User talk:Kventin|talk]]) 06:13, 28 August 2019 (UTC)

Talk:2170: Coordinate Precision

2019-07-03T08:04:29Z

Kventin:

The coordinates seem to show a NASA building, so in the end you're still soing something space related. [[Special:Contributions/172.69.55.196|172.69.55.196]] 19:47, 1 July 2019 (UTC)Some random European.
:The more precise coordinates are actually in the middle of the Rocket Garden at the Visitor's Center of the Kennedy Space Center complex. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 19:58, 1 July 2019 (UTC)

The atom-level coordinates are obtained by appending digits of e and pi to the Rocket Garden coordinates. [[User:Ichoran|Ichoran]] ([[User talk:Ichoran|talk]]) 20:21, 1 July 2019 (UTC)

I always find it very funny to see all those decimals. Regular GPS devices have an uncertainty of 3 meters if there is no interference from trees, buildings or whatever. That puts you at about 4 to 5 decimals I guess. [[User:Palmpje|Palmpje]] ([[User talk:Palmpje|talk]]) 20:26, 1 July 2019 (UTC)
:A Google Maps webpage URL includes coordinates to seven decimal places. [[User:EmuSam|EmuSam]] ([[User talk:EmuSam|talk]]) 20:48, 1 July 2019 (UTC)
::Sure but out there with your handheld GPS or normal consumer device that includes a GPS receiver you won't get more precision than about 3 meters. And when your at the higher latitudes you're probably not getting that. [[User:Palmpje|Palmpje]] ([[User talk:Palmpje|talk]]) 20:52, 1 July 2019 (UTC)

So combining this comic with #2169, is Randal suggesting he'll be at the Rocket Garden on July 28th (much as he did in #240)? [[Special:Contributions/108.162.216.208|108.162.216.208]] 20:47, 1 July 2019 (UTC)
:It says ''June'' 28th. --[[Special:Contributions/162.158.126.22|162.158.126.22]] 20:52, 1 July 2019 (UTC)
::No, the date of that comic is June 28, but the title text says: [AT THE JULY 28TH MEETING] --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 21:51, 1 July 2019 (UTC)
:::Ah, that makes sense. For some reason my app only showed the first part of the tirle text --[[Special:Contributions/162.158.126.94|162.158.126.94]] 23:04, 1 July 2019 (UTC)
::::The COMIC says "June 28th." The TITLE TEXT says "July 28th." Apparently the government computer predictive text was trained from different input. [[User:Mwburden|mwburden]] ([[User talk:Mwburden|talk]]) 15:26, 2 July 2019 (UTC)

Regrettably, there are two dimensions missing, Z and T. Without Z (elevation)+/- you could be in space or in a neutrino detector. T is only relevant for dynamic objects, but there again, the Americas are going West at a measurable rate! [[User:RIIW - Ponder it|RIIW - Ponder it]] ([[User talk:RIIW - Ponder it|talk]]) 21:30, 1 July 2019 (UTC)

The seventh row is likely a reference to comic number 1358 where two stick figures try to find waldo via satellite. [[Special:Contributions/172.69.226.125|172.69.226.125]] 21:44, 1 July 2019 (UTC) kisara, 21:42, 1 July 2019 (utc)

10^-40 degrees on the surface of the earth translates to about 0.7 planck lengths. [[Special:Contributions/162.158.106.234|162.158.106.234]] 21:50, 1 July 2019 (UTC)

Do the coordinates 28.5234°N, 80.6830°W really correspond to the tip of the Delta rocket? I checked and it was pointing to a small patch of ground next to the rocket, not the tip of the rocket itself. [[User:Herobrine|Herobrine]] ([[User talk:Herobrine|talk]]) 00:20, 2 July 2019 (UTC)
:No, you need to go to five decimal places to get the rocket. In that respect, I think he might be off by one digit of precision in his descriptions. [[User:Jeremyp|Jeremyp]] ([[User talk:Jeremyp|talk]]) 12:04, 2 July 2019 (UTC)

I would like to mention that neither number seems to fit into a standard double float value. I made a fiddle showing this. [https://dotnetfiddle.net/k7yK0Y#] [[User:Ansarya|Ansarya]] ([[User talk:Ansarya|talk]]) 01:48, 2 July 2019 (UTC)
:Floats are stored base 2, so representing them exactly as decimal often requires many more digits than is actually necessary (for complicated number theory reasons, a float can always be represented exactly as decimal, which would not be true if floats were stored in base 3). For this reason, programming languages that can format floats round them, usually to a number of digits where it will be possible to reconstruct the original float (though C# apparently takes off a couple extra digits, since those digits are almost never significant). To illustrate this, I used Rust to print many more digits of a float than would be shown normally [https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=6796c2459ceabea1a03d7113b676dd8f]. The latitude coordinate in the comic could be the result of printing a double precision float, but the longitude coordinate could not be. Also note that it takes almost 50 digits to reach an exact base 10 representation, even though only 14 or 15 of those digits are actually needed to reconstruct the original float. [[User:Probably not Douglas Hofstadter|Probably not Douglas Hofstadter]] ([[User talk:Probably not Douglas Hofstadter|talk]]) 18:01, 2 July 2019 (UTC)

May be my pet peeve... ...but adding an additional error to every piece of input data [and maybe every intermediate result] in order to show that either the precision the original measurement ends here or that all further digits of the measurement read "0" often introduces an error that can add up surprisingly quickly => I personally prefer raw floats that indicate there probably was no error analysis to rounded data and won't get tired on telling people to explicitely state what precision they can expect.[[Special:Contributions/162.158.114.70|162.158.114.70]]

If the smallest subnormal 32 bit float is a Planck length, then the largest 32 bit float is 10 sextillion times the diameter of the observable universe. If the value 1.0 of a 64 bit float is a cubic Planck length, then the largest float is 100 sextillion ''googol'' times the volume of the observable universe. [[User:Probably not Douglas Hofstadter|Probably not Douglas Hofstadter]] ([[User talk:Probably not Douglas Hofstadter|talk]]) 17:21, 2 July 2019 (UTC)

It'd be neat to have a map that shows the precision of given coordinates; like how Google Maps shows transparent blue circle with a wider radius if it's location detection isn't very precise. [[Special:Contributions/172.69.170.76|172.69.170.76]] 19:10, 2 July 2019 (UTC)

Something about the formatting of the table seems to be messing up the main page. Not sure what it is, but it happens just after the '110 km (70 mi)' so might be related to the span. Not a major problem as it's fine on the comic page and the main page will change tomorrow anyway. [[User:A(l)Chemist|AlChemist]] ([[User talk:A(l)Chemist|talk]]) 19:43, 2 July 2019 (UTC)

/\
/ \
/____\
information is people
[[Special:Contributions/172.68.34.172|172.68.34.172]] 01:27, 3 July 2019 (UTC)

"more than a quintillion times smaller" that's short scale quintillion, right?
[[User:Kventin|Kventin]] ([[User talk:Kventin|talk]]) 08:04, 3 July 2019 (UTC)

Talk:2161: An Apple a Day

2019-06-12T07:18:16Z

Kventin: question pertaining analogy to fictional extinct human subspecies

I get that I shouldn't, but after the first sentence in the second paragrsph, I really wanted to say:
"For example, if an opponent controls a thief of sanity and you have a sharktocrab, you may adapt the sharktocrab to tap down the thief."
(This is a Magic: The Gathering reference.) [[Special:Contributions/172.68.142.197|172.68.142.197]] 18:05, 10 June 2019 (UTC)

The title text contains a subtle pun with Gran-negative, where the bacterial term is Gram-negative, but instead is referring to Granny-Smith apples - hence, gran-negative. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 18:06, 10 June 2019 (UTC)
:And this is why I come to explainxkcd even when I think I have understood the comic! Thanks![[Special:Contributions/172.69.55.178|172.69.55.178]] 18:22, 10 June 2019 (UTC)

I felt parts of the explanation were worded a bit clunkily. I'm not strongly attached to my edit, so if others disagree, feel free to revert ;-) [[User:Gir|-- //gir.st/]] ([[User talk:Gir|talk]]) 19:10, 10 June 2019 (U

I feel I must take issue with the statement in the explanation that Granny Smith Apples are 'sour' and agree with the title text that they are 'tart' or possibly 'sharp'. [[User:RIIW - Ponder it|RIIW - Ponder it]] ([[User talk:RIIW - Ponder it|talk]]) 21:21, 10 June 2019 (UTC)

I've found that one apple a day will keep the doctor away, providing you can throw it hard enough and accurately enough at him. [[User:RAGBRAIvet|RAGBRAIvet]] ([[User talk:RAGBRAIvet|talk]]) 01:41, 11 June 2019 (UTC). Or her...

Antibiotics weren't my first thought on reading this comic, but rather mosquitoes, which have an amazing tendency to overcome everything we throw at them. There was an article a day or two ago about introducing spider venom into fungus to try a new approach against them. I'm sure there are other examples that occur to others, as resistance increase is a common enough concept. Like many xkcd, it works on multiple levels. [[User:Daemonik|Daemonik]] ([[User talk:Daemonik|talk]]) 08:58, 11 June 2019 (UTC)

:In looking for that, I found interesting item about how some mosquitos are insensitive to DEET (added to explanation). Thanks for the pointer. [[Special:Contributions/162.158.107.25|162.158.107.25]] 19:58, 11 June 2019 (UTC)

We could put our apples on a messaging site that posts to an uncensorable blockchain like https://memo.sv/ so that everybody can reuse others on doctors that haven't seen them yet. What do you think? I was also thinking if a strong AI were developed, it could build new apples as needed. Maybe an AI could be made rapidly by having it learn to predict its own behavior from its code. But you wouldn't want it to accidentally take over the world, so it could have a primary task of being interviewed in an empathic way, answering for example, "are you happy with how fulfilled your need to nurture and empower life is?" Answering this question in depth might stimulate it to understand these concepts, and the response would give the interviewer lots of avenues to understand and verify it further. By the way, there's a 30-page booklet on a technique used to resolve wars rapidly [https://gateway.ipfs.io/ipfs/QmdFVjYwgeuUpw83hBB74Wy4js8SrmmNxt8U2MkdRA2f7m/Books/We%20Can%20Work%20It%20Out:%20Resolving%20Conflicts%20Peacefully%20and%20Powerfully.pdf here]. [[Special:Contributions/172.69.68.143|172.69.68.143]] 02:08, 11 June 2019 (UTC)

[[User:J Milstein|J Milstein]] ([[User talk:J Milstein|talk]]) 13:01, 11 June 2019 (UTC) Apples keeping doctors away seems analogous to garlic keeping vampires away [[User:J Milstein|J Milstein]] ([[User talk:J Milstein|talk]]) 13:01, 11 June 2019 (UTC)

: If apples are to garlic as doctors are to vampires, comparing apples and oranges is like comparing doctors to whom?
: Also, if apples means stairs, what does garlic mean? [[User:Kventin|Kventin]] ([[User talk:Kventin|talk]]) 07:18, 12 June 2019 (UTC)

Talk:2042: Rolle's Theorem

2018-09-07T07:41:59Z

Kventin:

Now we wait for https://en.wikipedia.org/wiki/Munroes_theorem. [[Special:Contributions/172.69.54.165|172.69.54.165]] 15:51, 5 September 2018 (UTC)
:Can't wait to see how long it takes to remove the article. [[User:Linker|Linker]] ([[User talk:Linker|talk]]) 17:05, 5 September 2018 (UTC)

:Proposed ideas for Munroe's Law:
::- Any seemingly simple idea will be difficult to prove; the simpler it seems, the harder the proof.
::- Any proof which is discovered by a layperson will have been previously discovered by an expert (or an "expert") in the field.
:[[User:Rajakiit|Raj-a-Kiit]] ([[User talk:Rajakiit|talk]]) 17:57, 5 September 2018 (UTC)
:I do not have the time to do it good, so here a suggestion: Would someone go to the wikipedia page of Rolle's theorem and add a "in popular culture" section? may be a first? Not even "Nash equilibrum" has that :-) [[Special:Contributions/162.158.234.16|162.158.234.16]] 08:13, 6 September 2018 (UTC)
::Speaking of popular culture, there's a (moderately) well known Ballad of Rolle's theorem [https://www.youtube.com/watch?v=S0BXv90MlhA Balada o vete Rolleovej] ("moderately" meaning some people who studied at Faculty of mathematics in Bratislava might have heard (of) it) --[[User:Kventin|Kventin]] ([[User talk:Kventin|talk]]) 07:41, 7 September 2018 (UTC)

I feel like Euclid beat Randall to the punch here, a couple millennia. [[Special:Contributions/162.158.155.146|162.158.155.146]] 16:54, 5 September 2018 (UTC)

I don't see that Thales has proven Randall's theorem. Do not to be confused with {{w|Thales's theorem}}, that's about right angles. Maybe I'm blind or just dumb, but if so it has to be explained with more traceable background. I just believe that this diagonal is so trivial that even the ancient Greeks weren't engaged on a proof. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:38, 5 September 2018 (UTC)
* From {{w|Thales|Wikipedia}}: Other quotes from Proclus list more of Thales' mathematical achievements: "They say that Thales was the first to demonstrate that the circle is bisected by the diameter, the cause of the bisection being the unimpeded passage of the straight line through the centre." [[User:Alexei Kopylov|Alexei Kopylov]] ([[User talk:Alexei Kopylov|talk]]) 05:39, 6 September 2018 (UTC)
* On the other hand not all historian believe Proclus. But van der Waerden does: [https://books.google.com/books?id=HK3vCAAAQBAJ&pg=PA88#v=onepage&q&f=false]. [[User:Alexei Kopylov|Alexei Kopylov]] ([[User talk:Alexei Kopylov|talk]]) 05:49, 6 September 2018 (UTC)

:''Rolle's Theorem counterexample?''
Isn't the TAN(x) function a counterexample to this? Starting at a given point, it rises to infinity, then returns from negative infinity to the same point without ever having a slope of zero. [[Special:Contributions/172.68.58.89|172.68.58.89]] 06:58, 6 September 2018 (UTC)
:TAN(x) isn't differentiable at pi/2, hence the theorem doesn't apply--[[Special:Contributions/162.158.92.40|162.158.92.40]] 07:48, 6 September 2018 (UTC)
::And tan(x) has a slope of 0 at pi, so even if it applied, it wouldn't prove it wrong. A better example would be 1/x, but still invalid. [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 08:01, 6 September 2018 (UTC)
:::Nope: tan(x) has a slope of 1 at pi, and its slope is never less than 1. Of course, that doesn't make it a counterexample. Zetfr 09:17, 6 September 2018 (UTC)

''Clueless Museum Visitor''

The math in the comic is well explained, but shouldn't there be something about the "math equivalent of the clueless art museum visitor..." part? Zetfr 09:17, 6 September 2018 (UTC)
: Seconded, all the argument here is about math that isn't even *in* the comic, whereas the bit that confuses me is the cultural metaphor... [[Special:Contributions/162.158.154.235|162.158.154.235]] 07:16, 7 September 2018 (UTC)

Just so we're on the same page, while the proof of Rolle's theorem is not completely trivial, neither is it difficult by any means. Proving it seems to be a pretty common homework assignment in undergrad math classes, for example, so one might legitimately ask why it deserved to be named. Perhaps it's simply that it's old enough that the methods at the time were crappy, and so modern proofs are much easier. [[Special:Contributions/172.69.22.140|172.69.22.140]]
: It is named because it's a very important theorem in calculus, used to prove many other theorems or results. So when you need to prove something using this property, instead of re-demonstrating it or merely saying "it is well known that..." (which often raises alarm bells in the mind of the reader/corrector), all you have to do is reference Rolle's theorem.[[Special:Contributions/162.158.155.158|162.158.155.158]] 11:08, 6 September 2018 (UTC)
:: It could almost be called "Rolle's lemma". [[Special:Contributions/162.158.154.103|162.158.154.103]] 12:28, 6 September 2018 (UTC)
: When I am teaching Rolle's theorem, I always make it a point to draw the link to reals. Rolle's theorem fails when the output is complex valued. Then you can see for yourself how non-trivial this is. [[Special:Contributions/162.158.165.124|162.158.165.124]] 04:40, 7 September 2018 (UTC)

Has anyone else noted the irony of having a wiki page to explain a comic whose subject is how some things are self-evident? [[User:JamesCurran|JamesCurran]] ([[User talk:JamesCurran|talk]]) 20:13, 6 September 2018 (UTC)

Does the Kepler Conjecture actually belong on that list at the end? Most of the others are "derp" level intuitively obvious and/or essentially tautological on a very basic level, but the Kepler Conjecture couldn't actually be exhaustively proven until machine computation, nor is it intuitively definitive--if you've ever stacked round things into a box you've noticed that it feels like you're wasting a lot of space at the edges. So...? [[User:AtrumMessor|AtrumMessor]] ([[User talk:AtrumMessor|talk]]) 21:37, 6 September 2018 (UTC)

I also suggest that Fundamental Theorem of Calculus be removed from this list. Firstly, the beginner student, just introduced to derivatives and antiderivatives, will not easily see that antiderivatives are the same as finding areas under curves. Instead, it is only obvious upon hindsight, after instruction. More importantly, a restriction of the FTC to better-behaved spaces shows a far greater insanity: the restricted FTC is a consequence of generalised Stokes's theorem '''applied twice'''. This operation is so highly unintuitive, that one simply cannot claim that this is in any way, shape, or form, trivial. I think that trying to pretend that anything in beginning calculus is obvious to students is just going to alienate them rather than soothe their worries. [[Special:Contributions/162.158.165.124|162.158.165.124]] 04:40, 7 September 2018 (UTC)

"Munroe's theorem" should definitely refer to the circle thing in the alt text