Potency, Act, Relation, 'The Cause of Causes: First in Intention Last in Actuality'

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There can be no causality without potency, because an effect is something received, and reception is potency- for it is the ability to have some thing, say heat or color. Now insofar as something is potential to heat or color, then that same thing is it fulfillment, completion, and perfection, and so there is no causality without perfection either. The perfection, then, causes the potency to be exactly what it is, even before that same perfection is actually received materially. This requires the perfection to be present in a non-material way. 

Take a seed from an orange. There is a real ability in it to become an orange tree, and so there is something in it that exists only in relation to a tree. On the one hand, if one of the terms of a relation does not exist, the the relation must be only in the mind; and on the other hand this relation is really present within the seed, making it to have the real power that it has to become another. And so the innermost nature of things is a certain participation in mind- even the nature of our own mind is a certain participation in mind. This participation in mind is precisely what makes causality possible, and it therefore allows for an exposition of causes, or science. This argument- whether one agrees with it or not-concludes to the possibility of science.We have concluded, cleaned up shop, and gone home before any of the metrical sciences even set down a unit to measure with.