— 427 —
Fourthly, Names of simple Ideas least doubtful.       §15. Fourthly, But though the Names of simple Ideas, have not the
help of Definition to determine their signification; yet that hinders
not but that they are generally less doubtful and uncertain, than those
of mixed Modes and Substances. Because they standing only for one
simple Perception, Men, for the most part, easily and perfectly
agree in their signification: And there is little room for mistake and
wrangling about their meaning. He that knows once, that Whiteness
is the Name of that Colour he has observed in Snow, or Milk, will
not be apt to misapply that Word, as long as he retains that Idea;
which when he has quite lost, he is not apt to mistake the meaning of
it, but perceives he understands it not. There is neither a multipli-
city of simple Ideas to be put together, which makes the doubtfulness
in the Names of mixed Modes; nor a supposed, but an unknown
real Essence, with properties depending thereon, the precise
number whereof are also unknown, which makes the difficulty in
the Names of Substances. But on the contrary, in simple Ideas the
whole signification of the Name is known at once, and consists not
of parts, whereof more or less being put in, the Idea may be varied,
and so the signification of its Name, be obscure, or uncertain.
Locke Hum III, 4, §15, p. 427