Modern mathematical proofs are so complex that it's becoming impossible to prove them with absolute certainty. About a 1980 proof, an expert says "twenty-five years later we're still not sure if it's correct or not. We sort of think it is, but no one's ever written down the complete proof". I don't think I heard my math teachers ever say "sort of".
...is a weblog about the liberal arts 2.0 edited by Jason Kottke since March 1998 (archives). You can read about me and kottke.org here. If you've got questions, concerns, or interesting links, send them along.