The problem, of course, is that, while rejecting Locke’s doctrine of ideas, Reid maintained Locke’s nominalism. So the abstract predicates found in his propositions, even propositions pertaining to universal incorrigible principles, remain constructs of human language. Propositions are only ordered to particulars, the stuff of sense perception. This is the beginnings of the “correspondence theory of truth,” of course, for which, as a Thomist myself, I have naught but contempt. The classic metaphysician justifiably asks, “correspondence to what?!”

So my question still is: What is a Reformed view on ideas, propositions, abstraction, etc? For me, a great place to jump off with a rejection of Reid is with Christian theistic exemplarism (e.g. Bavinck’s and Van Til’s exemplarism). If there are divine exemplar ideas of universals natures, then how do those universals exist amongst/in particulars in some real way? Standing behind propositions are definitions, definitions taken from the most formal aspect of natural items. What is that intrinsic formality that renders a natural item both the effect of a divine intellect while also a principle of intelligibility itself so as to be known by finite intellects?