Explain xkcd: It's 'cause you're dumb.
'Undeclared' is sometimes called "General Studies".
Here's a YouTube video of "I Am the Very Model of A Modern Major's General"  for those who need to get the tune.
Here's is Tom Lehrer's Elements.
And here is Supercalifragilisticexpialidocious from Mary Poppins.
In panel 4, Methyl acetate is the solvent used to remove stamps from their envelope.
In panel 8, underwater basket weaving is a commonly used metaphor for any college major that is easy or worthless.
In panel 25, supermoon and zodiac are terms invented not by astronomers, but rather by early astrologists.
In panel 26, agronomy is the science of using plants as food or fuel, while the unrelated agoraphobia is the fear of wide open spaces.
And Sophie's Choice is any dilemma where choosing one cherished person or thing over the other will result in the death or destruction of the other, derived from the theme of the novel, and has also been turned into a romantic drama film.
People have done renditions of this song. See 
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I think Iambic Octameter has a stressed-unstressed pattern, not the other way around as this explanation says. 126.96.36.199 02:56, 10 April 2017 (UTC)
- No, the explanation is correct, I misread the Wikipedia article. 188.8.131.52 13:41, 16 April 2017 (UTC)
Panel 1's cueball is in the same pose as Rodin's "The Thinker"
Panel 4 background is the periodic table of elements.
Panel 5, Fowler's Toad emits a noxious secretion that irritates skin and mucous membranes (it was previously thought to cause warts)
Panel 6, Psychology = a serial killer with a chainsaw, Sociology = hobo; Social Psych = hobo serial killer with chainsaw.
Panel 15, LISP, Scheme, and other computer languages with an excess of parentheses.
Panel 16, biohazard symbol
Panel 19, bongos were played by Richard Feynman
Panel 27, fear of snakes, study of reptiles
Panel 28, a picture of a stomach, pun on "stomach" being slang for "tolerate"
Panel 30, words in all lowercase like e.e.cummings
-- 184.108.40.206 22:04, 7 December 2012
- Hobo serial killer with chainsaw? Social psych sounds awesome!
- 220.127.116.11 22:42, 22 October 2013 (UTC)
In panel 22 (History), what's the theme connecting the years 1935, 1969, and 1991?
Wwoods (talk) 15:40, 21 May 2013 (UTC)
- 1935 is certainly related to some event that lead to the WWII (a quick look at the Wikipedia page for 1935 show that was the year Hitler rearmed Germany), which paved the way to the Cold War. 1969 was Apollo 11, a high moment of the Cold War, as the USA essentially won the race to the Moon. And 1991 was the year that the USSR dissolved, officially ending the Cold War. Sir labreck (talk) 18:37, 11 August 2015 (UTC)
- 1935, Harlem race riot; 1969, race riot in Kuala Lumpur, Malaysia; 1991, Rodney King race riots... 2014-2016??? 18.104.22.168 03:33, 13 December 2015 (UTC)
This explanation is very small for that big comic. I am starting to add the transcript and after that I will do more investigations to that opera. This should be the key to explain all the panels.--Dgbrt (talk) 19:13, 21 May 2013 (UTC)
- The answer won't lie in the song, trust me. Pirates of Penzance is probably my favorite comic opera out there. Plus Randall gives that the lie in saying you can use the tune from the elements song (a well-known parody) or even Marry Poppins (similar tune, but not exactly the same). I think each panel is just a reference to the words, I don't think that Randall is actually involving The Pirates of Penzance in any way other than the tune. 22.214.171.124 20:53, 9 December 2013 (UTC)
Feynman was also known for being a ladies' man, so the two girls in panel 19 are significant IMHO.
--126.96.36.199 13:51, 25 December 2013 (UTC)
Needs explanation what does it mean to choose a major, and what major is in this context. Note every reader is from U.S.A.; different countries have different higher education systems. --JakubNarebski (talk) 10:56, 9 January 2014 (UTC)
- True that. 'Graduation' in Brazil means 'Undergraduation' in the US. 188.8.131.52 03:51, 1 February 2014 (UTC)
"Math's just physics unconstrained by precepts of reality" - that isn't a binary tree, its a bifurcation diagram from chaos theory. And, sorry, it has nothing to do with the Banach–Tarski paradox - that's just mindless name-dropping.
Davidbak (talk) 20:54, 10 February 2014 (UTC)
- Are you sure it is not just an illustration of Banach-Tarski, arguably the most famous example where mathematical reality and (physical) intuition diverge? Why would the verse be illustrated by a bifurcation diagram (which I think, and I might be a bit ignorant here, is a concept pretty much only found in the "applied side" of mathematics, which is constrained by precepts of reality)? And even if it were a bifurcation diagram, why would the mass of the balls change? (again, I am perhaps showcasing my ignorance; if so, please be gentle) Finally, i would deem the bifurcation explanation a bit too obscure to be the real deal - a panel which is only understood by somewhat specialized mathematicians seems strange to me, especially given that all other frames contain understandable references. 184.108.40.206 13:38, 9 October 2015 (UTC)
https://www.youtube.com/watch?v=pRexBMPeRToHalfhat (talk) 18:59, 3 April 2014 (UTC)
Panel 30: possibly iambic septameter220.127.116.11
I think that the reason for not getting hugs in panel 16 is more to do with the fact that as a virus researcher you would be aware of how easy it is to get a virus/disease and so you would keep away from people and be worried about hugs because of that. (Sorry if I've done something wrong this is my first comment!) Yxquillio (talk) 08:24, 3 January 2016 (UTC)
Another song I guess could provide a good match is "Can You Stop the Calvary?" by Jona Lewie (or "Where's the Modding API" if you're a YOGSCAST fan like me. :)) --JayRulesXKCD (talk) 11:50, 20 September 2016 (UTC)
"End of the first verse where Cueball tells his academic advisor that he is undecided as every major's terrible. He even throws away his study guide." Are you sure it's not a course catalog? 18.104.22.168 10:33, 19 June 2017 (UTC)