Completely fair point, that I do not think I have the knowledge to speak on. On the Trigonometry Wikipedia page, he pops up a few times, and many trig identities are known as pythagorean identities. Perhaps its not fully trig, but was used as a basis to help discover trig? Without having the understanding pythagorus gave mathematicians regarding triangles, I would think it would be pretty hard to begin developing deeper math regarding said triangles