Proclus, a Greek mathematician who lived several centuries after Euclid, wrote in his commentary of the Elements: "Euclid, who put together the Elements, collecting many of Eudoxus' theorems, perfecting many of Theaetetus', and also bringing to irrefragable demonstration the things which were only somewhat loosely proved by his predecessors".
Proclo, un matemático grego que viviu varios séculos despois de Euclides, escribiu no seu comentario dos Elementos: "Euclides, que recompilou os Elementos, recollendo moitos dos teoremas de Eudoxo, perfeccionando moitos dos de Teeteto e tamén proporcionando demostracións irrefutábeis de cousas que foran só debilmente probadas polos seus predecesores".