12. Names of substances referred, to real essences that cannot be known.
The names of substances have, as has
been shown, a double reference in their ordinary use.
First, Sometimes they are made to stand for, and so their signification is supposed to agree to, the real constitution
of things, from which all their properties flow, and in which they all centre. But this real constitution, or (as it is
apt to be called) essence, being utterly unknown to us, any sound that is put to stand for it must be very uncertain
in its application; and it will be impossible to know what things are or ought to be called a horse, or antimony,
when those words are put for real essences that we have no ideas of at all. And therefore in this supposition, the
names of substances being referred to standards that cannot be known, their significations can never be adjusted
and established by those standards.