(That's from about 4 centuries after Euclid. It would really help to have manuscripts from Euclid's time -- for example, it's suspected others added the definit

(That's from about 4 centuries after Euclid. It would really help to have manuscripts from Euclid's time -- for example, it's suspected others added the definitions later and perhaps injected a neopythagorean POV not in the original.)