,
believe, and reason; yet, it must be borne in mind, that there is an
important difference between the signification of the terms when applied
to them and when applied to those animals which possess language. The
thoughts of the former are trains of mere feelings; those of the latter
are, in addition, trains of the ideas of the signs which represent
feelings, and which are called "words."

A word, in fact, is a spoken or written sign, the idea of which is, by
repetition, so closely associated with the idea of the simple or complex
feeling which it represents, that the association becomes indissoluble.
No Englishman, for example, can think of the word "dog" without
immediately having the idea of the group of impressions to which that
name is given; and conversely, the group of impressions immediately
calls up the idea of the word "dog."

The association of words with impressions and ideas is the process of
naming; and language approaches perfection, in proportion as the shades
of difference between various ideas and impressions are represented by
differences in their names.

The names of simple impressions and ideas, or of groups of co-existent
or successive complex impressions and ideas, considered _per se_, are
substantives; as redness, dog, silver, mouth; while the names of
impressions or ideas considered as parts or attributes of a complex
whole, are adjectives. Thus redness, considered as part of the complex
idea of a rose, becomes the adjective red; flesh-eater, as part of the
idea of a dog, is represented by carnivorous; whiteness, as part of the
idea of silver, is white; and so on.

The linguistic machinery for the expression of belief is called
_predication_; and, as all beliefs express ideas of relation, we may say
that the sign of predication is the verbal symbol of a feeling of
relation. The words which serve to indicate predication are verbs. If I
say "silver" and then "white," I merely utter two names; but if I
interpose between them the verb "is," I express a belief in the
co-existence of the feeling of whiteness with the other feelings which
constitute the totality of the complex idea of silver; in other words, I
predicate "whiteness" of silver.

In such a case as this, the verb expresses predication and nothing else,
and is called a copula. But, in the great majority of verbs, the word is
the sign of a complex idea, and the predication is expressed only by its
form. Thus in "silver shines," the ve