I was about to post this masterpiece. The self interpreter is like some sort of Platonic mathematical treasure, like the Gosper Glider Gun or the Monster Group.

I was about to post this masterpiece. The self interpreter is like some sort of Platonic mathematical treasure, like the Gosper Glider Gun or the Monster Group. (Please feel free to suggest other examples.) [edit: some more off the top of my head; the Burning Ship, minimal ZFC-undecidable Turing machine[0], Milnor's 7-Sphere) [0] https://www.scottaaronson.com/busybeaver.pdf https://www.scottaaronson.com/busybeaver.pdf