e operation
of cutting off _his_ head, which are all particulars; but we do not
naturally dwell upon what is meant by the word 'head' or the word
'cut', which is a universal: We feel such words to be incomplete and
insubstantial; they seem to demand a context before anything can be
done with them. Hence we succeed in avoiding all notice of universals as
such, until the study of philosophy forces them upon our attention.

Even among philosophers, we may say, broadly, that only those universals
which are named by adjectives or substantives have been much or often
recognized, while those named by verbs and prepositions have been
usually overlooked. This omission has had a very great effect upon
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 any one 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.