Title text: "This is the reference implementation of the self-referential joke."
Douglas Hofstadter is an American author who has written several books about philosophy, mathematics, and science. He is perhaps most famous for his book Gödel, Escher, Bach which explores "strange loops," or self-referential systems. "Meta-" is a Greek prefix meaning "outside" or "beyond." As an adjective, "meta" informally refers to anything self-referential, like this sentence.
At first reading, the six word biography in the second panel, "I'm So Meta, Even This Acronym", may seems unfinished, however the clue is in the final word. An acronym is an abbreviation formed by the initial components of a series of word, so reading the first letters of the words in order yields "IS META." Thus the intended reading of the biography is "I'm so meta, even this acronym is meta", setting up the self-reference.
In the title text, reference implementation is a reference to the standard implementation during a software development process.
Additionally, around the time of this comic the "explain <insert whatever here> in six words" meme was making the rounds.
Hofstadter had already been referenced in the title text of 555: Two Mirrors and 608: Form. Furthermore his famous book has been directly spoofed in the title of 24: Godel, Escher, Kurt Halsey. Finally the self-reference reference - IS META - is also a typical concept used most famously in 688: Self-Description but also very early in 33: Self-reference and in the title text of 442: xkcd Loves the Discovery Channel.
- [Cueball sits at a desk, working on a laptop. Megan approaches the desk and picks up a tiny book.]
- Megan: What's this?
- Cueball: Douglas Hofstadter's six-word autobiography. After all those 700-page tomes, I guess he wanted to try for brevity.
- Megan: Huh. Let's see...
- [Close up of Megan, reading the tiny book.]
- Book: I'm So Meta, Even This Acronym
- [Full shot of Cueball and Megan again. Megan looks down at the tiny book in her hand.]
- Megan: ...whoa.
- Cueball: I think he nailed it.