8. Common use, or propriety not a sufficient remedy.
It is true, common use, that is, the rule of propriety may be
supposed here to afford some aid, to settle the signification of language; and it cannot be denied but that in some
measure it does. Common use regulates the meaning of words pretty well for common conversation; but nobody
having an authority to establish the precise signification of words, nor determine to what ideas any one shall
annex them, common use is not sufficient to adjust them to Philosophical Discourses; there being scarce any name
of any very complex idea (to say nothing of others) which, in common use, has not a great latitude, and which,
keeping within the bounds of propriety, may not be made the sign of far different ideas. Besides, the rule and
measure of propriety itself being nowhere established, it is often matter of dispute, whether this or that way of
using a word be propriety of speech or no. From all which it is evident, that the names of such kind of very
complex ideas are naturally liable to this imperfection, to be of doubtful and uncertain signification; and even in
men that have a mind to understand one another, do not always stand for the same idea in speaker and hearer.
Though the names glory and gratitude be the same in every man's mouth through a whole country, yet the
complex collective idea which every one thinks on or intends by that name, is apparently very different in men
using the same language.