Though to be honest, by modern standards Euclid sneakily uses some extra assumptions in his proofs that you actually need to add as axioms. See https://math.st

Though to be honest, by modern standards Euclid sneakily uses some extra assumptions in his proofs that you actually need to add as axioms. See https://math.stackexchange.com/q/1901133/1051561 https://math.stackexchange.com/q/1901133/1051561 for some examples.