18. V.g. Putting them for the real essences of substances.
It is true the names of substances would be much more
useful, and propositions made in them much more certain, were the real essences of substances the ideas in our
minds which those words signified. And it is for want of those real essences that our words convey so little
knowledge or certainty in our discourses about them; and therefore the mind, to remove that imperfection as much
as it can, makes them, by a secret supposition, to stand for a thing having that real essence, as if thereby it made
some nearer approaches to it. For, though the word man or gold signify nothing truly but a complex idea of
properties united together in one sort of substances; yet there is scarce anybody, in the use of these words, but
often supposes each of those names to stand for a thing having the real essence on which these properties depend.
Which is so far from diminishing the imperfection of our words, that by a plain abuse it adds to it, when we would
make them stand for something, which, not being in our complex idea, the name we use can no ways be the sign
of.
