On the other hand, to deny that esse as 'actuality' falls under any concept additional to a thing's essence, and that it is predicable only as the function of some form it actualises, is not to reduce the predication of esse to equivocal vacuousness, as if to say that there is no distinction between a thing's esse and the essence it actualises, or as if predications of existence are entirely redundant. For in saying that a thing's esse is not distinct from it by virtue of being some additional form, it is not entailed that a thing's esse and its essence are identical, and so must be equivocally predicated of everything of which it is true. This, as Thomas explains, does not follow, and in any case could not be true. There must be a real distinction between what it is that exists and that by virtue of which it exists. For any two individuals which belong to a common genus share something of a common form, as a man and a horse do, both being animals. Likewise, any two individuals of the same species share in that the same form is predicable of them both, as two human beings do. But no two individuals can share a common esse in the sense of actuality: a horse's esse is distinct from a man's, as Socrates' esse is distinct from Plato's, or else when Socrates dies Plato dies too. Hence, in whatever belongs to a genus there is necessarily a real distinction between that which it is (quod quid est) and the (substantial) form by which it is what it is on the one hand, and its being actual - that by which it is, on the other.16 It does not follow, therefore, from the fact that esse is not a 'form' distinct from a thing's essence that it is identical with the essence it actualises, and therefore is predicated equivocally of all the things which exist. Esse, to repeat what Thomas says, is the actualisation of form: it is not itself a formal actualisation.
Was this article helpful?