nominalism, in philosophy, a theory of the relation between universals and particulars. Nominalism gained its name in the Middle Ages, when it was contrasted with realism. The problem arises because in order to perceive a particular object as being of a certain kind, say a table, we must have a prior notion of table. Does the kind
described by this prior notion, then have an existence independent of particular tables? Nominalism says that it does not, that it is just a name for a group of particular objects. Nominalism is appropriate to materialist and empirical philosophy and hence has been popular in modern thought.
See R. A. Eberle, Nominalistic Systems (1970).