philosophy; it is hardly too much to say that most metaphysics, since Spinoza, has been largely determined by it. The way this has occurred is, in outline, as follows: Speaking generally, adjectives and common nouns express qualities or properties of single things, whereas prepositions and verbs tend to express relations between two or more things. Thus the neglect of prepositions and verbs led to the belief that every proposition can be regarded as attributing a property to a single thing, rather than as expressing a relation between two or more things. Hence it was supposed that, ultimately, there can be no such entities as relations between things. Hence either there can be only one thing in the universe, or, if there are many things, they cannot possibly interact in any way, since any interaction would be a relation, and relations are impossible.
The first of these views, advocated by Spinoza and held in our own day by Bradley and many other philosophers, is called monism ; the second, advocated by Leibniz but not very common nowadays, is called monadism , because each of the isolated things is called a monad . Both these opposing philosophies, interesting as they are, result, in my opinion, from an undue attention to one sort of universals, namely the sort represented by adjectives and substantives rather than by verbs and prepositions.
As a matter of fact, if anyone were anxious to deny altogether that there are such things as universals, we should find that we cannot strictly prove that there are such entities as qualities , i.e. the universals represented by adjectives and substantives, whereas we can prove that there must be relations , i.e. the sort of universals generally represented by verbs and prepositions. Let us take in illustration the universal whiteness . If we believe that there is such a universal, we shall say that things are white because they have the quality of whiteness. This view, however, was strenuously denied by Berkeley and Hume, who have been followed in this by later empiricists. The form which their denial took was to deny