Nominalism is the doctrine that abstract concepts, ideas, and universals exist only as spoken words and have no other independent existence. We describe Joey and Fluffy as cats both, not because of some intrinsic "cattiness" quality, common to each, that has a real, ideal, or metaphysical existence of its own, but rather because both cats fall into an acceptable range of physical stimuli that we agree to describe as the spoken word "cat." Blood and fire ants do not carry less-than-ideal forms of "redness," rather, they both reflect light within the range of particular wavelength that we, in our supreme intellectual capacity, decided to call red.

To declare that each and every physical stimuli has its own universal is to maintain that all possible stimuli or, moreover, combination of stimuli, have ideal copies, and thus every possible real situation exists seperately and is somehow more "ideal;" this constitutes an infinite regress and an unnecessary multiplication of entities, illogically complicated and explaining nothing.

The admirable philosophy of universals is perhaps Plato's best, and many philosophers after him. But I am inclined to believe that nominalism has a greater probability of being more correct, though I do not necessarily want that to be the case.