https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&user=162.158.150.88&feedformat=atomexplain xkcd - User contributions [en]2024-03-28T13:39:31ZUser contributionsMediaWiki 1.30.0https://www.explainxkcd.com/wiki/index.php?title=2246:_Christmas_Presents&diff=1852212246: Christmas Presents2019-12-28T17:13:47Z<p>162.158.150.88: /* Explanation */</p>
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<div>{{comic<br />
| number = 2246<br />
| date = December 25, 2019<br />
| title = Christmas Presents<br />
| image = christmas_presents.png<br />
| titletext = "The parasitism might be mediated by a fungus!" exclaimed the biologist who was trying to ruin Christmas again.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created using the [[User:DgbrtBOT|BOT template]]. Please mention here why this explanation isn't complete. Explain more about parasitic plant and how fungus can help them grow. Do NOT delete this tag too soon.}}<br />
This is the second comic in a row about presents, this one in particular calls them {{w|Christmas gift|Christmas presents}}, and it was also released on {{w|Christmas}} Day. It is thus the second [[:Category:Christmas|Christmas comic]] in a row after [[2245: Edible Arrangements]].<br />
<br />
A {{w|Christmas tree}} cut down from the woods will typically be placed in a living-room soon after being cut down, and left standing there through the holiday season. On {{w|Christmas Eve}} or {{w|Christmas Day}}, or even earlier, presents are typically put beneath the tree under the lower branches. Once the tree is cut down, it will eventually start turning brown and/or losing its needles as it no longer receives any nutrients from its roots.<br />
<br />
Based on this observation (on Christmas Day) some biologist (or [[Randall]]) concludes that the presents are a type of {{w|parasitic plant}}—that is, a plant that derives some or all of its nutritional requirement from another living plant. Since such a plant can use the sugars produced by the parasitised tree it does not necessarily have to perform photosynthesis by itself (although some parasitic plants such as mistletoe are photosynthetically active). If the parasitic plant is not doing photosynthesis it can live in the shade beneath a tree that it parasitizes as it has no need for light, and since it does not need chlorophyll either may not be green (e.g. {{w|Orobanche}}. With the presents often being wrapped in bright white and red colored paper, Randall concludes that this indicates a lack of chlorophyll, thus fitting with the idea of a parasitic plant. <br />
<br />
With the presents being in the shade of the tree and the tree's health suffering, the evidence can only lead to the conclusion that Christmas presents are parasitic plants.<br />
<br />
In the title text a biologist says that "The parasitism might be mediated by a fungus!" While many parasitic plants attach themselves directly to the plant they are parasitising (e.g. mistletoe) this is obviously not the case with the christmas presents which are not growing out of the christmas tree - which appears to rule out a parasitic relationship. However, the biologist has an answer for that: Some parasitic plants (such as {{w|sarcodes|snow flowers}}) do not attack the tree directly but instead form a conection to mycorhizal {{w|Fungus|Fungi}}. These fungi are receiving sugars form the trees an provide it in turn with mineral nutrients. By parasitising these fungi the snow flower can steal the sugars of the tree indirectly, one says that the fungi is mediating the parasitism.<br />
<br />
Randall dismisses these words as coming from a biologist who is "trying to ruin Christmas again", which could have several meanings. It could be that the biologist really is just trying to ruin Christmas, and is trying to be more successful than in previous years by tying Christmas presents to fungus in people's minds. One might say that the biologist is not a "fun guy" for doing this.<br />
<br />
It could instead be the case that the biologist is quite earnest in his belief that Christmas presents are harmful plant parasites and is attempting to spray the presents with a {{w|fungicide}}, which would probably be toxic and potentially contaminate not only the wrapping paper but also the presents inside their boxes. <br />
<br />
Finally, it could be that the biologist is right, and Christmas presents are hosts to or otherwise associated with a parasitic fungus (and Randall's dismissal is a sign of his infection). There are some parasitic fungi that hijack the brains of host animals and alter their behavior. The most famous of these is probably ''{{w|Ophiocordyceps unilateralis}}'', the so-called "zombie ant fungus", which causes its hosts to perch on a high plant to maximize the distance traveled by the fungus's spores. Ants have in turn developed strategies for detecting and removing infected members from the colony's territory. None of these fungi are known to infect humans, but they did inspire the zombie fungus in ''{{w|The Last of Us}}''.<br />
<br />
==Transcript==<br />
:[A Christmas tree decorated with 16 balls and a star at the top with a high trunk with space for several presents beneath. About 13 presents with different patterns of paper and some with strings around. Three arrows with text at the blunt end points towards different areas. To the left one points to a present, beneath this one points to the area beneath the tree (the bottom of one present) and to the right one points to the tree.]<br />
:Bright white and red colors indicate a lack of Chlorophyll<br />
:Flourishing in the shade<br />
:Tree health suffering<br />
<br />
:[Caption beneath the panel:]<br />
:The evidence is clear: Christmas presents are parasitic plants.<br />
<br />
{{comic discussion}}<br />
<br />
<!-- Include any categories below this line. --><br />
<br />
[[Category:Christmas]]<br />
[[Category:Biology]]</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=Talk:2233:_Aurora_Meaning&diff=183670Talk:2233: Aurora Meaning2019-11-26T09:12:54Z<p>162.158.150.88: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
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Hey guys. As you can tell by the edit logs, I'm removing a spam comment that was made in bad faith. I'm new here so please let me know what the actual procedure is for, ya know, spam deletion and logging. <br />
Have an outstanding day, --[[User:OtterlyAmazin|OtterlyAmazin]] ([[User talk:OtterlyAmazin|talk]]) 03:46, 26 November 2019 (UTC)<br />
:Great you removed [https://www.explainxkcd.com/wiki/index.php?title=Talk%3A2233%3A_Aurora_Meaning&type=revision&diff=183613&oldid=183612 this text]. I guess if this account keeps doing such things it should be banned. Sadly we seem to have lost all contact to any admin of the page...? So I'm not sure how we could do anything. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:01, 26 November 2019 (UTC)<br />
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Nobody talks about the visible shadow of the two lower texts? You can clearly see a layer of grey letters, not identical to the topmost layer, benath. [[Special:Contributions/172.68.141.52|172.68.141.52]] 05:57, 26 November 2019 (UTC)<br />
:I have no idea what you are talking about. I see no shadows on neither xkcd or the image uploaded here? Maybe it is your device that is making the shadows... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:01, 26 November 2019 (UTC)<br />
::On the words Satelite and Exciting in the southern hemisphere it is most visible (but also on others) that there are greyish letters right next to the black ones, kinda like shadows. Maybe Randall copy pasted and changed it. Similar things of remains of erased parts have been visible before. (If someone thinks it is important, I can try to look it up, but I am not exactly sure where it was) --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 08:38, 26 November 2019 (UTC)<br />
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Do we have any indication how much energy we're talking to see the aurora at the equator? or how that would physically work? [[Special:Contributions/162.158.159.38|162.158.159.38]] 08:17, 26 November 2019 (UTC)<br />
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There has been an equatorial aurora exactly once in human history. [https://en.wikipedia.org/wiki/Starfish_Prime Starfish Prime] was an orbital nuclear detonation that, among other things, disabled multiple satellites and created a temporary artificial aurora 16° north. That is also likely what the sub-tropical band is referring to. [[Special:Contributions/162.158.150.88|162.158.150.88]] 09:12, 26 November 2019 (UTC)</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1927:_Tinder&diff=1490721927: Tinder2017-12-11T21:19:48Z<p>162.158.150.88: Other lifes affected</p>
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<div>{{comic<br />
| number = 1927<br />
| date = December 11, 2017<br />
| title = Tinder<br />
| image = tinder.png<br />
| titletext = People keep telling me to use the radio but I really hate making voice calls.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Do NOT delete this tag too soon.}}<br />
<br />
{{w|Tinder (app)|Tinder}} is a social media/dating app. The main interface of Tinder shows photos of people using the app. Users swipe right for matches that they like, and left otherwise. The purpose of the app is to get dates, with the intent of a romantic relationship or sexual intercourse. However, in the comic, [[Cueball]] is trying to use it to get assistance flying a plane instead.<br />
<br />
The title text implies that Cueball is doing this because he finds it annoying to use the plane's radio, which he finds too similar to making a phone call. The joke is about his bad priorities in using an ill-suited app which would be slower than asking for help on the radio. He is endangering the life of himself and any possble passengers, just to avoid the annoyance of having to talk on the phone.<br />
<br />
This comic is similar to [[1897: Self Driving]].<br />
<br />
==Transcript==<br />
<br />
:[An iPhone-esque device is shown with the screen facing the viewer. On the screen is the Tinder UI. The main photo is of Cueball, in the cockpit of a plane which appears to be tilting to the right, holding up a sign saying:]<br />
:If you know how<br />
:to fly a plane<br />
:please swipe<br />
:right ASAP<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Social networking]]</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=975:_Occulting_Telescope&diff=144379975: Occulting Telescope2017-08-22T11:49:47Z<p>162.158.150.88: /* Explanation */ +Hitchhiker's Guide to the Galaxy</p>
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<div>{{comic<br />
| number = 975<br />
| date = November 09, 2011<br />
| title = Occulting Telescope<br />
| image = occulting_telescope.png<br />
| titletext = Type II Kardashev civilizations eventually completely enclose their planetary system in a Dyson sphere because space is way too big to look at all the time.<br />
}}<br />
<br />
==Explanation==<br />
[[Cueball]] takes the useful practice of {{w|occulting}} stars beyond its intended purpose. Occulting is used to block the light from a star under observation so that adjacent dim objects, such as any {{w|extrasolar planets|surrounding planets}}, might be more easily detected and examined. Instead of blocking the light of a single star for the purposes of observation, Cueball proposes blocking the light from all stars, for the purpose of making him feel comfortable with the night sky. Cueball feels, some might say irrationally, that "there are too many stars, and it's been ''freaking [him] out''".<br />
<br />
The title text refers to both a {{w|Kardashev scale|Type II Kardashev civilization}} and a {{w|Dyson sphere}}.<br />
<br />
A Dyson sphere is a theoretical construction consisting of a network of satellites that orbit and completely surround a star. The purpose to capture and transmit all of the available solar energy back to a planet.<br />
<br />
A Type II Kardashev civilization is a theoretical civilization that has advanced to the point where it has harnessed the energy radiated by its own star (for example, the stage of successful construction of a Dyson sphere).<br />
<br />
For comparison purposes:<br />
*A Type I Kardashev civilization is one that has harnessed the energy of their entire planet.<br />
*A Type III Kardashev civilization is one that has harnessed the energy of their entire galaxy.<br />
*We are currently less than I.<br />
<br />
The title text reveals that Type II Kardashev civilizations construct Dyson spheres not for the purposes of capturing all solar energy, but merely to block the view of all that hideous space. This may allude to Douglas Adam's Hitchhiker's Guide to the Galaxy novel series, where a planet called Krikkit is completely obscured by a dust layer. Upon building a spacecraft to explore what lies behind that dust cover, they decide to destroy all living beings in the rest of the universe. See http://hitchhikers.wikia.com/wiki/Krikkit.<br />
<br />
The concept of an occulting space telescope was visited again in [[1730: Starshade]].<br />
<br />
==Transcript==<br />
:[Cueball is presenting his new telescope in front of a white board, pointing to the diagram of said telescope with a pointer. He is standing on a raised podium facing a crowd off-panel]<br />
:Cueball: The occulting observatory consists of two parts—the telescope and the discs.<br />
<br />
:[A frame-less panel with a black center with white drawings that shows the diagram from the white board in the first panel. It shows a satellite with solar panels above and below the main body which has a front end that looks wider like a telescope. The satellite is labeled with a small arrow pointing at the front end. 11 light waves are indicated as coming towards it from the right, and below these they are labeled. Three of the waves is blocked in the middle by a small vertical line which is also labeled with a small arrow. Above and below the diagram outside the black area Cueball is narrating.]<br />
:Cueball (narrating): When the telescope sees a star, a disc is carefully steered to block its light.<br />
:Label: Telescope<br />
:Label: Light from star<br />
:Label: Disc<br />
:Cueball (narrating): This procedure is repeated until all stars are covered.<br />
<br />
:[Back to Cueball on the podium who now looks down on the audience from where a question emanates at the top of the left frame.]<br />
:Person #1 (off screen): Wait, ''all?'' Why?<br />
:Cueball: I'll feel better.<br />
<br />
:[Close-up on Cueball. as two different persons talks to him, from the lower left frame.]<br />
:Person #2 (off-screen): I thought the point was to image extrasolar planets.<br />
:Cueball: The point is that there are ''too many stars.'' <br />
:Cueball: It's been freaking me out.<br />
:Person #2 (off-screen): What?<br />
:Person #3 (off screen): <small>He has a point...</small><br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Astronomy]]<br />
[[Category:Space]]<br />
[[Category:Exoplanets]]<br />
[[Category:Public speaking]]<br />
[[Category:Telescopes]]</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1866:_Russell%27s_Teapot&diff=1430551866: Russell's Teapot2017-07-21T19:10:29Z<p>162.158.150.88: /* Explanation */</p>
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<div>{{comic<br />
| number = 1866<br />
| date = July 21, 2017<br />
| title = Russell's Teapot<br />
| image = russells_teapot.png<br />
| titletext = Unfortunately, NASA regulations state that Bertrand Russell-related payloads can only be launched within launch vehicles which do not launch themselves.<br />
}}<br />
==Explanation==<br />
{{incomplete|How big and how reflective must the teapot be in order to be seen by telescopes on earth?}}<br />
{{w|Russell's teapot|Russell's Teapot}} is a philosophical argument that reflects on the difficulty of trying to prove a negative. It involves a hypothetical teapot orbiting a heavenly body, whose existence hasn't been proven, and states that it cannot be disproven (Somebody put it there secretly?). It is very often used in atheistic arguments. Russell's Teapot is an analogy which {{w|Bertrand Russell}} devised "to illustrate that the philosophic burden of proof lies upon a person making unfalsifiable claims, rather than shifting the burden of disproof to others."<br />
<br />
<blockquote>"He wrote that if he were to assert, without offering proof, that a teapot orbits the Sun somewhere in space between the Earth and Mars, he could not expect anyone to believe him solely because his assertion could not be proven wrong." (Wikipedia)</blockquote><br />
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[[Cueball]] is trying to settle the teapot argument by actually launching a teapot into space via a {{w|crowdfunding}} campaign.<br />
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"{{w|CubeSat}}-based design" refers to a type of miniaturized satellites that is made up of 10-centimeter cube units (here seemingly consisting of 3 units) and enables cost-effective means for getting a payload into orbit.<br />
<br />
The title-text refers to {{w|Russell's paradox}}, also formulated by Bertrand Russell. Russell's paradox was a flaw found in {{w|naïve set theory}} where one could consider "the set of all sets that do not contain themselves" (a "set" is a mathematical term for a "group of things"). The paradox arises with whether this set, in turn, contains itself: if it does, then it cannot; if it doesn't, then it must. Similarly, like in the {{w|barber paradox}}, the vehicle which launches only vehicles which do not launch themselves is impossible: if the vehicle takes off, it must launch itself as well as the teapot, and thus can never be launched (without violating alleged NASA regulations, at least).<br />
<br />
==Transcript==<br />
<br />
:[Cueball is standing in front of a blueprint labeled "CubeSat-Based Design", containing a satellite with a teapot in the top.]<br />
<br />
:[Caption below the panel:]<br />
:I'm crowdfunding a project to launch a teapot into orbit around the sun to settle the Russell thing once and for all.<br />
<br />
{{comic discussion}}<br />
[[Category:Comics featuring Cueball]]</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1829:_Geochronology&diff=1392771829: Geochronology2017-04-26T11:44:05Z<p>162.158.150.88: /* Explanation */</p>
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<div>{{comic<br />
| number = 1829<br />
| date = April 26, 2017<br />
| title = Geochronology<br />
| image = geochronology.png<br />
| titletext = 'The mountains near here formed when the ... Newfoundland ... microplate collided with, uhh ... Labrador.' 'Ok, now you're definitely just naming dogs.' 'Wait, no, that's actually almost correct.'<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Please add some more information on Newfoundland geology. Could somebody elaborate on why the title text is ''almost'' correct?}}<br />
[[Ponytail]] is describing the origin of some rock formations to [[Megan]] and [[Cueball]]. She apparently forgot the names of the {{w|Plate tectonics|microplates}} and the {{w|Geologic time scale|age}} when the {{w|subduction}} occurred, so she substituties them with names of {{w|Dog breed|dog breeds}} ({{w|Dalmatian (dog)|Dalmatian}}, {{w|Laika (dog breed)|Laika}} and {{w|Pomeranian (dog)|Pomeranian}}) to seem knowledgeable and impress her audience. <br />
<br />
Although and no microplates and geological ages with these names exist, this is not obvious for people outside of the field, as dog breeds are often named after geographic regions. For example {{w|Dalmatia|Dalmatia}} is the name of a region in Croatia, and a microplate named after it could exist. Likewise, the Laika plate could be named after the Laika island in Vanatu. Geological ages are often named after place where the first rocks dating from the age were found e.g. the {{w|Devonian}} is named after the English county of {{w|Devon}}, while the {{w|Permian}} is named after the Russian city of {{w|Perm}}. Thus, a pomeranian age named after {{w|Pomerania}} might reasonably exist.<br />
<br />
The title text highlights this problem: At first it seems that that Megan continues using dog breeds to name microplates, but the explanation is actually correct: The dog breeds {{w|Labrador|Labrador Retriever}} and {{w|Newfoundland (dog)|Newfoundland}} are named after two canadian regions - as are two microplates, whose relative movement did indeed led to the formation of mountains in Newfoundland.<br />
<br />
Subduction was featured in a previous comic [[1388: Subduction License]].<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
:[Cueball, Ponytail, and Megan are standing in a field.]<br />
:Ponytail: [Gesturing toward a rock formation] This bedrock likely formed as the Dalmatian microplate subducted under East Laika during the Upper Pomeranian.<br />
:Cueball: [Touching his chin thoughtfully] Ah, yes.<br />
<br />
:[Caption below the panel:]<br />
:Geology Tip: There are so many microplates and ages that no one remembers them all, so in a pinch you can bluff with dog breeds.<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Ponytail]]<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Megan]]<br />
[[Category:Geography]]</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=Talk:1818:_Rayleigh_Scattering&diff=138291Talk:1818: Rayleigh Scattering2017-04-04T06:59:54Z<p>162.158.150.88: </p>
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<div><!--Please sign your posts with ~~~~--><br />
I keep trying to correct the misspelled joung Girl to Young Girl but it keeps reverting. I corrected the two non-capitalized sentences and they stay put. Does "joung" have a meaning i don't understand? [[User:ExternalMonolog|ExternalMonolog]] ([[User talk:ExternalMonolog|talk]]) 14:55, 31 March 2017 (UTC)<br />
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No, "joung" is only there, because of my limited english skills [[Special:Contributions/162.158.150.88|162.158.150.88]] 06:59, 4 April 2017 (UTC)<br />
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:There might be conflicting edits, that happens a lot with new comics[[User:Dontknow|Dontknow]] ([[User talk:Dontknow|talk]]) 15:34, 31 March 2017 (UTC)<br />
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Question - while I understand the intent of the comic is that overly complicated explanations can be confusing, isn't the title-text analogy incorrect? Doesn't chlorophyll scatter green light and absorbs other colors, whereas with the sky, it's really just different levels of scattering and very little absorbing (hence why a clear sky at dusk can appear red, the sky wasn't absorbing red light, it was just scattering it differently than blue light). Isn't that fundamentally different from the way most other common objects get their perceived color? (ps - I'm not a scientist, just curious, appreciate any feedback)<br />
:Sry, no answer to your question, but a second chlorophyll-related one: I doubt that chlorophyll "reflects" green light, "scattering" should be correct! Any other opinions???? milebrega, 14:38, 1 April 2017 (UTC)<br />
<br />
"Why are leaves green?" "Well, the leaf absorbs most of the colors, but not the green light, which it scatters instead." "Why is my shirt black?" "Well the cloth absorbs most of the colors, but just scatters the black light... wait..." [[User:Andyd273|Andyd273]] ([[User talk:Andyd273|talk]]) 15:46, 31 March 2017 (UTC)<br />
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I like to think this is Miss Lenhart, continuing her science teaching in the same vein as in 'Venus'. There's no proof in the comic, but it fits nicely. Potentially something to add as a possibility in the explanation? [[Special:Contributions/162.158.154.247|162.158.154.247]] 16:38, 31 March 2017 (UTC)<br />
:I second the take that this is Miss Lenhart; I guess she's not in a classroom setting but she's been in similar situations. Someone should mention that the girl's second question is the same from [[803: Airfoil]] (also with Miss Lenhart). Articles have mentioned sort of "series" of themes before; that article, [[1145: Sky Color]], and this have an ongoing theme of "how to explain science to kids".[[Special:Contributions/172.68.150.34|172.68.150.34]] 04:04, 1 April 2017 (UTC) <br />
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Yesssss <3 I had the exact same thought the first time Rayleigh scattering was explained to me: "isn't that just a specific mechanism of air being blue?" For some reason such explanations majorly tend to insist that the air is not in fact blue, and it has always bothered me. [[Special:Contributions/162.158.111.19|162.158.111.19]] 16:41, 31 March 2017 (UTC)<br />
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Maybe the explanation should point out that the real reason the planes "stay up" is that the tiny birds are on the '''underside''' of the wings.--[[Special:Contributions/162.158.92.34|162.158.92.34]] 17:20, 31 March 2017 (UTC)<br />
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If air is blue how come a sunset, with LOTS of air, is red? I know the answer but it is the obvious next question with this explanation. [[Special:Contributions/162.158.74.171|162.158.74.171]] 17:22, 31 March 2017 (UTC)<br />
:During the day the Sun heats the air. At sunset you see the result of this heating, the air glows red-hot or orange-hot and starts to quickly cool down. You can't see it glowing during the day because of the very bright Sun.--[[Special:Contributions/162.158.92.34|162.158.92.34]] 17:40, 31 March 2017 (UTC)<br />
::Oh ok. Than why is the sun-rise also red? ;-). --[[User:DaB.|DaB.]] ([[User talk:DaB.|talk]]) 23:40, 31 March 2017 (UTC)<br />
:: https://www.reddit.com/r/ExplainLikeImCalvin/ [[Special:Contributions/108.162.210.202|108.162.210.202]] 10:31, 1 April 2017 (UTC)<br />
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Can someone add this to the comics featuring those respective characters? [[User:Dontknow|Dontknow]] ([[User talk:Dontknow|talk]]) 17:41, 31 March 2017 (UTC)<br />
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New here, probably not following proper form in this commend, but, if I may ask, is that thing about mountains appearing blue actually true? (Unsigned)<br />
<br />
I received the 'rayleigh scattering' explanation myself, and it served me well. Even without knowing anything about quantum mechanics or how the human eye works, knowing that there's an optic principle at work other than simple pigmentation explains why the light is golden early and late in the day, and why dust or smoke can have such diverse effects on the colour of the light beaming down, especially at dusk and dawn.<br />
<br />
If I'd been told air was blue, I'd have a lot more questions, and I'd still think that gemstones like alexandrite that look different colours in different light were somehow magical, instead of just having unique physical properties. So, I'd like to assume Randall's just making a outlandish joke, not really trying to say that it's wrong to give children the phrase 'rayleigh scattering' and explain what the consequences of it are, even without describing the mechanisms behind it--something that still goes way over my head.[[User:Namaphry|Namaphry]] ([[User talk:Namaphry|talk]]) 04:59, 1 April 2017 (UTC)<br />
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Air is not blue - certainly not in the same way that leaves are green or blue-dyed liquids are blue. This is evident when observing the Moon - a large chunk of rock much farther away than any mountains. Does all the air we're looking through at it make it appear blue? Of course not. If anything, the Moon can appear orange near the horizon. (But clearly, the reason is not that "air is orange".)<br />
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""Air is not blue - certainly not in the same way that leaves are green or blue-dyed liquids are blue. ""<br />
Have You ever seen liquid air or oxygen? <br />
[[Special:Contributions/162.158.92.52|162.158.92.52]] 06:29, 2 April 2017 (UTC)<br />
: Actually no. And a google image search for Liquid Oxygen doesn't give an image I'm totally convinced is actually of Oxygen (Best match seems to be a flask of Ozone, although it is most certainly a very deep blue). <br />
<br />
: Air in the Earth's atmosphere is not liquid, nor does it contain liquid oxygen. While liquid oxygen is pale blue, gaseous oxygen is colorless. Feel free to check the Wikipedia page on oxygen for a quick reference. [[Special:Contributions/172.68.215.88|172.68.215.88]] 08:21, 3 April 2017 (UTC)<br />
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What is happening with the sky is that air can appear to glow with various colors when illuminated with a strong directional source of light, such as the sun. The color depends on multiple factors, including the angle of illumination and observation. The glow can be commonly seen being blue, white, yellow, or red - with blue hues generally observable on clear days, and reddish hues at sunrise or sunset. This only works with a directional source of light; when the source of light is diffuse, such as under a large cloud cover, the sky doesn't appear blue, and neither do distant mountains, readily disproving the notion that air itself would be blue.<br />
<br />
There. That didn't involve any quantum mechanics. [[Special:Contributions/172.68.215.88|172.68.215.88]] 07:07, 1 April 2017 (UTC)<br />
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Is there no xkcd April Fool's this year? <span style="font-size:13px;"><span style="font-weight:light;">~</span>[[User:Luc|Luc]]</span>&nbsp;<span style="font-size:10px;"><span>[</span>[[User talk:Luc|talk]]<span>]</span></span> 22:27, 1 April 2017 (UTC)<br />
<br />
<br />
;Current explanation all backwards?<br />
I seriously doubt the point of the comic is to tell children wrong answers just because they might not understand the real answer. That is just horrible. "The child's reaction in this comic, "Wow!", suggests that not only she understood, but is also excited about learning, which could be more important to her development than hearing the "correct" answer up front." That doesn't make any sense. I'm sure he doesn't want to say, tell children planes fly because of birds in their wings. There are easy and simple ways to give the correct answer, that children will understand, and it's definitely not better for their development and interest to tell them absolut BS. It's the other way around, he makes fun of this answer, and so wants to make the point to NOT tell children things like that just because you're too lazy to explain, or because you think they might not understand. The point is not: Give an easy and possibly wrong answer to children. The point is rather: While for blue sky the easier (and TRUE) answer might be enough for kids, for other things that's not the best solution, and definitely don't oversimplify so much that your answer actually is wrong. [[Special:Contributions/162.158.88.98|162.158.88.98]] 08:53, 1 April 2017 (UTC)<br />
:I completely agree. I find the current explanation to be 100% the opposite of what Randall has been trying to say in earlier comics. The joke is those that think it is better to tell false stories rather than try to tell the truth. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 18:28, 1 April 2017 (UTC)<br />
<br />
Look, there's really no question about whats going on in this comic, and people need to stop overcomplicating and overanalyzing things. Here's how it breaks down: Science Girl asks a science question. Blondie gives a simplified but still correct answer, while Megan gives the traditional but more complicated answer. Blondie then makes the point that's also the comic's intended moral - that we can view things at different levels of detail, and that just because an explanation is less detailed than you're use to doesn't mean it's actually wrong.<br />
:Blondie is doing the child a disservice. It's debatable if "Because air is blue" is accurate as others gave the examples of with sunrise and sunset. Also dubious is her statement, "Blue light bounces off it and hits our eyes". This makes it sound like simple reflection which is a very distinct mechanism from scattering. Things that reflect light vs. things that allow some light to pass through them (glass, air, water, irises) get wavelengths to our eyes in different ways. If you give the completely useless "because it makes it so blue light gets to our eyes" you'd be correct, but saying that the light reflects rather than is scattered is false.[[Special:Contributions/162.158.79.5|162.158.79.5]] 15:25, 3 April 2017 (UTC)<br />
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Then in the last panel, Blondie takes her valid point to its illogical conclusion by giving an explanation that isn't merely simplified, but straight up wrong, which frustrates Megan. This panel has no moral and is not trying to make a point. It's just there to be the punchline. Anyone reading ''any'' kind of moral into it should probably remember why they're called "comics" in the first place.[[Special:Contributions/108.162.241.172|108.162.241.172]] 02:04, 2 April 2017 (UTC)<br />
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<br />
;Hommage to Calvin and Hobbes?<br />
I believe this comic could be an hommage to Calvin and Hobbes comics, where Calvin asks his dad stuff about nature, and his dad replies with completely nonsensical explanations.<br />
[[Special:Contributions/162.158.114.22|162.158.114.22]] 21:20, 1 April 2017 (UTC)<br />
:Calvin and Hobbes did not invent children asking science questions or parents who can't answer them.[[Special:Contributions/108.162.241.172|108.162.241.172]] 02:04, 2 April 2017 (UTC)<br />
::Lot's of homages exist to things that didn't invent other things.[[Special:Contributions/162.158.79.5|162.158.79.5]] 15:27, 3 April 2017 (UTC)<br />
<br />
== The other side of the argument ==<br />
<br />
The other side of the argument is basically that by giving an overly simple and inaccurate explanation, one can be very misleading. There is another take on the following sentence:<br />
<br />
The child's reaction in this comic, "Wow!", suggests that not only she understood, but is also excited about learning, which could be more important to her development than hearing the "correct" answer up front.<br />
<br />
That is that the child may be impressed by a mere superficiality. Did she really understand, or was the explanation in some way impressive? (Impressiveness does not imply correctness.)<br />
<br />
A person might say, "Wow!" to some Hollywood special effects. Does that really mean that the person is interested in how to create such effects? Does the girl in the strip really care to learn? If she does, starting off by telling her something wrong seems a rather odd way to go about it.<br />
<br />
When one starts in a field of study, one often needs to have simple explanations. Otherwise, the sheer mass of detail can be overwhelming. It is more useful to give an explanation that is more or less correct and to mention that there are special cases. An example is Einsteinian physics which obsoleted Newtonian physics, but the latter is still close enough to be useful in everyday situations.<br />
<br />
Additionally, if one gets in the habit of simplifying everything without regard to correctness, where does it end? The final frame gives an example of this.<br />
<br />
[[Special:Contributions/108.162.245.166|108.162.245.166]] 00:26, 2 April 2017 (UTC) (Gene Wirchenko <genew@telus.net><br />
<br />
== April fools day comic absense ==<br />
<br />
Where's the 2017 April fools day comic?? [[Special:Contributions/162.158.79.197|162.158.79.197]] 11:50, 2 April 2017 (UTC)<br />
<br />
I noticed that too... maybe its hiding. [[Special:Contributions/162.158.142.10|162.158.142.10]] 15:33, 2 April 2017 (UTC)</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1818:_Rayleigh_Scattering&diff=1381321818: Rayleigh Scattering2017-03-31T14:27:14Z<p>162.158.150.88: /* Transcript */</p>
<hr />
<div>{{comic<br />
| number = 1818<br />
| date = March 31, 2017<br />
| title = Rayleigh Scattering<br />
| image = rayleigh_scattering.png<br />
| titletext = If you ask "why are leaves green?" the usual answer is "because they're full of chlorophyll, and chlorophyll is green," even though "why does chlorophyll scatter green light?" is a great question too.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
See also [[1145]].<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
Can someone please check for false words and correct character names?<br />
<br />
:[2 Girls Talking]<br />
:joung Girl: Why is the sky blue?<br />
:Mother: Because air is blue<br />
:Megan: No, the sky is blue because of Rayleigh scattering -<br />
:Mother: Nah, it's because air is blue. Blue Light bounces off it and hit our Eyes. Same as why anything is any color<br />
:Mother: Its why far-off mountains look blue - because of all the blue air in the way.<br />
:Megan: There's a specific quantum mechanism by which -<br />
:Mother: Yeah(,) but there's a Physics mechanism for every color. You don't have to get all quantum right away<br />
:Megan: ... OK, I guess<br />
:Mother: Any other Questions?<br />
:joung Girl: How do planes stay up?<br />
:Megan: well, the airfloww -<br />
:Mother: tiny Birds in the Wings. Thousands. Flapping Hard.<br />
:joung Girl: WOW!<br />
:Megan: NO!<br />
<br />
{{comic discussion}}</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1818:_Rayleigh_Scattering&diff=1381301818: Rayleigh Scattering2017-03-31T14:21:24Z<p>162.158.150.88: /* Transcript */</p>
<hr />
<div>{{comic<br />
| number = 1818<br />
| date = March 31, 2017<br />
| title = Rayleigh Scattering<br />
| image = rayleigh_scattering.png<br />
| titletext = If you ask "why are leaves green?" the usual answer is "because they're full of chlorophyll, and chlorophyll is green," even though "why does chlorophyll scatter green light?" is a great question too.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
See also [[1145]].<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
31.03.2017 16:21 (MESZ) ---UNDER CONSTRUTION---<br />
<br />
:[2 Girls Talking]<br />
:Girl: Why is the sky blue?<br />
:Mother: Because air is blue<br />
:Megan: No, the sky is blue because of Rayleigh scattering -<br />
:Mother: Nah, it's because air is blue. Blue Light bounces off it and hit our Eyes. Same as why anything is any color<br />
<br />
{{comic discussion}}</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1818:_Rayleigh_Scattering&diff=1381291818: Rayleigh Scattering2017-03-31T14:20:17Z<p>162.158.150.88: /* Transcript */</p>
<hr />
<div>{{comic<br />
| number = 1818<br />
| date = March 31, 2017<br />
| title = Rayleigh Scattering<br />
| image = rayleigh_scattering.png<br />
| titletext = If you ask "why are leaves green?" the usual answer is "because they're full of chlorophyll, and chlorophyll is green," even though "why does chlorophyll scatter green light?" is a great question too.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
See also [[1145]].<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
:[2 Girls Talking]<br />
:Girl: Why is the sky blue?<br />
:Mother: Because air is blue<br />
:Megan: No, the sky is blue because of Rayleigh scattering -<br />
:Mother: Nah, it's because air is blue. Blue Light bounces off it and hit our Eyes. Same as why anything is any color<br />
<br />
{{comic discussion}}</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1818:_Rayleigh_Scattering&diff=1381281818: Rayleigh Scattering2017-03-31T14:15:00Z<p>162.158.150.88: /* Transcript */</p>
<hr />
<div>{{comic<br />
| number = 1818<br />
| date = March 31, 2017<br />
| title = Rayleigh Scattering<br />
| image = rayleigh_scattering.png<br />
| titletext = If you ask "why are leaves green?" the usual answer is "because they're full of chlorophyll, and chlorophyll is green," even though "why does chlorophyll scatter green light?" is a great question too.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
See also [[1145]].<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
-Why is the sky blue<br />
-Because air is blue<br />
-No, the sky is blue because of Rayleigh scattering<br />
<br />
{{comic discussion}}</div>162.158.150.88https://www.explainxkcd.com/wiki/index.php?title=1800:_Chess_Notation&diff=1356911800: Chess Notation2017-02-19T12:25:06Z<p>162.158.150.88: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 1800<br />
| date = February 17, 2017<br />
| title = Chess Notation<br />
| image = chess_notation.png<br />
| titletext = I've decided to score all my conversations using chess win-loss notation. (??)<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Please change this comment when editing this page and not remove it too fast.}}<br />
<br />
<br />
[[Cueball]] begins a conversation with [[White Hat]] with the declaration that he will be scoring his conversations using chess notation. White Hat is not interested, so the conversation dies out, with both Cueball and White Hat saying "Fine". And just as promised, Cueball has scored this particular conversation, giving it a '''½-½''', as he believes that this is a drawn conversation. The reasons for the draw, as explained below too, may be due to a stalemate (the conversation isn't going anywhere), draw by repetition (both players have played the same moves over and over again, and cannot improve their position - probably if "Fine" had been repeated more times), 50-move rule (the conversation has been going on fruitlessly for too long - unlikely here since it is only 4 dialogues long) or something else.<br />
<br />
The title text contains the same assertion that Cueball is scoring all his conversations in chess notation, followed by a (??). In chess notation, (??) means the move in question was a very bad move - a blunder. Cueball says that his decision to score all his conversations was a blunder, which is understandable as it turns conversations from something fun and rapport-building to a sort of war where one has to win over the other party. Also, Cueball may be treating his conversation itself like a chess game, and memorize openings, use tactics and evaluate various possible things to say, which will take away the light-heartedness of any conversation. Quite a ?? indeed!<br />
<br />
The ?? may also mean that Cueball and/or the persons he is having a conversation with are confused (??) by this decision, as seen here when White Hat says he doesn't know or care what that means.<br />
<br />
=== Chess notation (and annotation) ===<br />
<br />
{{w|Chess}} players and critics use certain {{w|chess notation|notations}} to write down chess games in a very short fashion (for example the {{w|Forsyth–Edwards Notation}}, which is both computer- and human-readable). In addition, ''{{w|chess annotation symbols}}'' like ! and !? help to comment certain moves in a similarly short fashion. That way it is possible to print or discuss a chess game (or a chess opening) in a limited space, for example in printed reference manuals.<br />
<br />
A short synopsis about common chess annotation symbols:<br />
<br />
!! – brilliant move: Very strong and counter-intuitive move. A sound sacrifice.<br/><br />
! – good move: A surprisingly good move.<br/><br />
!? – interesting move: Risky, or worthy of attention and analysis.<br/><br />
?! – dubious move: Designates a move that may be bad, but it is hard to explain why.<br/><br />
? – mistake: Poor move that should not be played.<br/><br />
'''??''' – {{w|blunder (chess)|blunder}}: Exceptionally bad move, usually designates a move that turns a winning position into a draw, or a draw into a losing position.<br/><br />
<br />
The score of the "white" player is always given first, followed by the score of the "black" player. Possible {{w|Chess tournament#Scoring|notations}} for the game outcome are:<br/><br />
<br />
1-0 – a win (for white) <br/><br />
0-1 – a loss (for white) <br/><br />
'''½-½''' – a draw <br/><br />
<br />
Because every chess game begins by moving a white piece, the following can be observed: When Cueball ends a conversation with 1-0,<br />
* he either began the conversation, and won it;<br />
* or he responded to a communication request, and lost the conversation.<br />
<br />
=== Draws in chess ===<br />
A chess game can be won (and lost for the other party) or {{w|draw (chess)|drawn}}. It should be noted that draws most commonly occur by {{w|Draw by agreement|agreement}}, or very rarely by {{w|stalemate}}. A stalemate is a situation where the opponent's king is not in check, but none of the opponent's pieces can be moved in a legal way. In a human conversation, what amounts to a draw, and what amounts to a stalemate? <br />
<br />
If agreed draws should be allowed (and under which circumstances) is a matter of some discussion among chess players, thus adding another point to Randall's comic. For example, some tournament rules (e.g. the so-called "{{w|Draw by agreement#Only theoretical draws allowed (Sofia Rules)|Sofia Rules}}") do not allow a draw to be offered directly - any player has first to announce the intention of drawing to the arbiter (referee), who then decides if the position should be played out further or not.<br />
<br />
The official chess rules offer some ways the concept of a "draw" could be applied to a human conversation. According to the {{w|World Chess Federation}} (FIDE) rules, a draw can occur:<br />
#by agreement. Any player can offer a draw when it is his turn to move.<br />
#by stalemate. As explained above: The king is not in check, but no legal moves are available.<br />
#when the same position (with the same possible legal moves) occurs at least three times, with the same player having the same possibilities of moving his pieces. This draw must be requested by the player. According to the FIDE rule 9.6, the arbiter himself declares the game drawn when the same position occurs five times.<br />
#when 50 moves have passed without a capture or a pawn move. Again, the draw occurs only upon request. According to the same FIDE rule 9.6, the arbiter declares the game drawn when 75 moves have passed, without a request by either player.<br />
#when one of the players has used up his time, but his opponent has not enough material to mate. For example, king and pawn mate against a king in certain situations, while king against king leads to a draw by the 50-move-rule.<br />
#when both players have used up their time, but the arbiter cannot determine who did so first. This is impossible with modern electronic chess clocks, though.<br />
#upon request, when the opponent does not play seriously and attempts to win the game by timeout.<br />
<br />
=== So, what's a "draw" in a conversation? ===<br />
*Draw agreed: As pointed out by Randall in his cartoon, a drawn conversation is one where all participants agree.<br />
*50-move-rule: Conversation is drawn, based on the excessive duration of the talk.<br />
*Draw by repetition: Both participants have talked in circles, arriving at the same conclusions all over again. No progress has been made.<br />
*Draw by stalemate: When A cannot convince B, but B doesn't have any legal argument left, and would have to resort to lies or logical fallacies in order to continue.<br />
<br />
=== Chess games and conversations ===<br />
The notion of applying chess scores to conversations begs the question if and how chess play and conversations can be compared.<br />
<br />
Chess games and human conversations do have some things in common:<br />
*The outcome fully depends on the behavior of the partner/opponent.<br />
*As in chess, there is no certainty that a certain statement will have the desired effect. The opponent can always react in a surprising way.<br />
*Chess players, like conversation partners, do not "calculate" the opponent's next move(s). They don't compute anything. They are not cold-blooded machines. They do, however, similar to conversation partners in a job interview or a televised debate:<br />
**create a plan, and revise and refine it as necessary<br />
**try to get a good feel of the situation, and try to remember how they dealt with a similar situation in the past<br />
**try to identify the opponent's weaknesses, and try to remedy one's own weaknesses. Prepare against surprises and pitfalls.<br />
**focus on a few promising moves, and quickly spot if they're easily refutable. "You see, I spent 8 years programming {{w|BANCStar programming language|BANCStar}} applications at..." - "Anybody with that experience is dangerous and should be locked up." - "Oh."<br />
*The question of what is considered a good move (or statement) can only be answered in a subjective way. Chess engines though use algorithms to assess the position, and they can calculate the value of different possible moves. In human conversations, social norms help avoid making bad moves.<br />
*It is difficult to win against an experienced, alert partner or opponent. Competent exploitation of the opponent's errors is often the only way to win.<br />
*In both, you will try to find moves that make your win more probable, while avoiding deleterious moves. Due to inadequate computing power, it is hitherto impossible to calculate all possible ways a chess game (or a conversation) could play out. See also [[1002: Game AIs]]. Therefore it is impossible to design a path that leads to a guaranteed outcome - except when the situation has been simplified enough. There are handbooks to play endgames, explaining how to secure either a win or a draw, no matter the capability of the opponent. Nowadays, computer-generated {{w|endgame tablebase}}s exist for six-piece and seven-piece endgames. Those for six pieces are freely available and are about 1 terabyte large.<br />
<br />
Differences:<br />
*Chess games are inherently competitive, zero-sum ventures; if one player wins, the other loses. In contrast, conversations aren't usually competitive, so there isn't really a concept of a winner and loser unless the conversation was an argument or debate. Often, both people in a ''friendly'' conversation will benefit ("win") from having had the conversation.<br />
*Both chess games and conversations are turn-based, but lacking time controls, people's statements sometimes last up to an hour.<br />
*Especially in disputes, (agreed) draws are extremely rare.<br />
*It is difficult to judge the winner of a conversation.<br />
*In chess, every position of the pieces can be analyzed completely independent of the previous moves. It does not matter how the situation evolved. After 1.e4 e5 and 1.e3 e6 2.e4 e5, there is an identical situation. Due to human emotions, though, this is not the case for conversations. No situation is ever exactly the same. <br />
*Chess games are extremely constrained by a set of rules. Players are expected to behave gentlemanly, and arbiters can hand out punishments for any behavior that brings the game into disrepute.<br />
<br />
==Transcript==<br />
:[Cueball and White Hat facing each other.]<br />
:Cueball: I've decided to score all my conversations using chess win-loss notation.<br />
:White Hat: I don't know or care what that means.<br />
:Cueball: Fine.<br />
:White Hat: Fine.<br />
<br />
:[Caption below the frame:]<br />
:½–½<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring White Hat]]<br />
[[Category:Chess]]</div>162.158.150.88