Main Page

Explain xkcd: It's 'cause you're dumb.
Revision as of 05:35, 4 March 2013 by Davidy22 (Talk | contribs)

Jump to: navigation, search

Welcome to the explain xkcd wiki!

We have collaboratively explained 5 xkcd comics, and only 1719 (34380%) remain. Add yours while there's a chance!

Latest comic

Go to this comic explanation

Next, let's assume the decision of whether to take the Axiom of Choice is made by a deterministic process ...
Title text: Next, let's assume the decision of whether to take the Axiom of Choice is made by a deterministic process ...


Ambox notice.png This explanation may be incomplete or incorrect: Created by a BOT - Please change this comment when editing this page.

The comic starts by setting up a situation that resembles a Proof by Contradiction. These often involve making an assumption that there exists some formula or figure that fulfills the requirements given and plucking that answer out of abstract mathematics, much like summoning of demons is associated with black magic. This is usually done by relying on knowledge of the constraints of the form (for example, having the square root of 2 be a/b where a and b are both integers and have no common factors when proving that the square root of 2 is irrational). This common usage is then shown to be not the case in the comic as the proof then goes to claim that the answer will be written in a specific place (though this could be taken as indicating that the result is finite or has a simple algorithm for continuing it).


[Party 1 is standing in front of a whiteboard facing left. Party 1 is presumably writing on it. Some existing writing is shown as left aligned scribbles.]
party 1: ...Let's assume there exists some function f(a, b, c...) which produces the correct answer-
Cueball interjects (off panel): Hang on.
[Cueball sitting at a desk]
Cueball: This is going to be one of those weird, dark magic proofs, isn't it? I can tell.
[Party 1 turned facing right.]
party 1: What? No, no, it's a perfectly sensible chain of reasoning.
Cueball (off panel): All right...
[Party 1 facing the whiteboard again. More scribbles have been added to the first, third, and fourth set of scribbles.]
party 1: Now, let's assume that the correct answer will eventually be written on the board at (x, y). if we-
Cueball interjects (off panel): I knew it!

Is this out of date? Clicking here will fix that.

New here?

You can read a brief introduction about this wiki at explain xkcd. Feel free to sign up for an account and contribute to the wiki! We need explanations for comics, characters, themes, memes and everything in between. If it is referenced in an xkcd web comic, it should be here.

  • List of all comics contains a complete table of all xkcd comics so far and the corresponding explanations. The red links (like this) are missing explanations. Feel free to help out by creating them! Here's how.


Don't be a jerk. There are a lot of comics that don't have set in stone explanations; feel free to put multiple interpretations in the wiki page for each comic.

If you want to talk about a specific comic, use its discussion page.

Please only submit material directly related to —and helping everyone better understand— xkcd... and of course only submit material that can legally be posted (and freely edited.) Off-topic or other inappropriate content is subject to removal or modification at admin discretion, and users who repeatedly post such content will be blocked.

If you need assistance from an admin, feel free to leave a message on their personal discussion page. The list of admins is here.

Personal tools


It seems you are using noscript, which is stopping our project wonderful ads from working. Explain xkcd uses ads to pay for bandwidth, and we manually approve all our advertisers, and our ads are restricted to unobtrusive images and slow animated GIFs. If you found this site helpful, please consider whitelisting us.

Want to advertise with us, or donate to us with Paypal?