18 July 2002

A couple of folks asked me to say something about nominalism--that is, the late medieval philosophical and theological perspective that goes by the title "nominalism" and is associated with thinkers such as William of Ockham and Gabriel Biel.

It seems to me that the best way to deal with this is in several posts, first briefly defining "nominalism", second explaing the philosophical and theological context in which it arose, and finally explaining what I take to be some of its disastrous results.

The term "nominalism" arises in the context of medieval discussions of universals and nominalists were opposed to realists with regard to universals. "Universals" are, roughly speaking, those aspects of reality that things share in common and are able to be understood by the human mind, abstracted from the particularities of the concrete, individual things themselves.

So, for instance, consider what it means for there to be "five" things in a group: five chairs, five glasses of water, five things to do before breakfast, five math equations in one's mind. Each of these groups has the quality of "fiveness" in terms of its membership and thus it is something that all of these groups share in common. A realist about universals would say that there really is such a thing as "fiveness" that each of these groups has. We can think about it, talk about it, and abstract it from the particular things. We can grasp this "fiveness" is such a way that, in the future when we come into contact with a completely new group of five things, we will recognize it as having this "fiveness" as well. When we apply the term "five" to these various groups, we are truly saying something about the reality of those groups, even if, given the differences between the groups, the term "five" is being used analogously (i.e., expressing similarity within difference).

Realists about universals may disagree about whether or not a universal like "fiveness" can exist apart from actual groups of five things, but they are all agreed that this quality of "fiveness" is something that really exists in the groups of things and is shared by them. Plato was a realist of one sort, Aristotle of another. So were Augustine, Anselm, and Aquinas.

Nominalists, on the other hand, deny the real existence of universals. For them things in themselves have no real commonalities at all, but are isolated individuals that are each unique. Thus when we attribute "fiveness" to various groups of things, we are using the term equivocally (i.e., expressing a completely different meaning) in terms of reference since there is no one thing that all these groups really have in common. Thus "fiveness" is really just a word, a name (nomina, thus "nominalism") that functions as a kind of mental "place-holder" through which we groups things for the purpose of convenience or function. The name taken in itself, indeed, is completely univocal (i.e., expressing one simple, undifferentiated meaning) and does little to communicate the reality of the individual things to which that name is applied.

This view had some earlier medieval precursors in Roscelin and Peter Abelard and was developed more fully in the later middle ages through the thinking of Henry of Ghent, John Duns Scotus, and especially William of Ockham.