15. Names of simple ideas of less doubtful meaning than those of mixed modes and substances.
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 multiplicity 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 is 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 name
be obscure, or uncertain.
