Martin wrote:

Weird.... I thought the pyramids pre-date Pythagoras by 1 or 2 millennia?



They do. And IIRC the Egyptians knew 3,4,5 but not the general rule
about the square of the hypotenuse etc. - which is what Pythagoras
discovered. Oh hang on...In another source...

http://en.wikipedia.org/wiki/Pythagorean_theorem

Andy