The causes and the principles, then, are three, two being the pair of contraries of which one is definition and form and the other is privation, and the third being the matter.
Horrela, bada, hiru dira kausak eta hiru dira printzipioak: bi kontrakotasunari dagozkio-bata, kontrakotasunaren esakunea eta forma da; bestea, haren eza-.