…there is a difference between what is constitutive of a thing and what constitutes it. Once we have located an object’s genus and specific difference, we have its essence – that which is constitutive of it. If we then find out that the object is constituted by something else, say by fundamental particles, what we discover is not its deeper essence but its material cause. Now the root material cause of all substances is prime matter, but since there is no matter without form, when we discover a thing’s constituents, whether fundamental or not, we discover proximate matter, i.e. its proximate material course, and this comes to us already packaged by form, as it were.
David Oderberg, “Real Essentialism” p 158.
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