Also, he wouldn't let you eat beans

Although Pythogoras is probably just semi-historical. Pythogoras himself would probably have been quite excited about the revelation, but among other things his cult attributed basically all existing math to him while also doing a really, really bad job of preserving any of his actual writings.

Anyways, "his" theorum was being used in Babylon and Egypt centuries before his birth. He just popularized it in Greece.