patterns or forms, (for, in that sense, the word FORM has a very proper
signification,) to which as particular things existing are found to
agree, so they come to be of that species, have that denomination, or
are put into that CLASSIS. For when we say this is a man, that a horse;
this justice, that cruelty; this a watch, that a jack; what do we else
but rank things under different specific names, as agreeing to those
abstract ideas, of which we have made those names the signs? And what
are the essences of those species set out and marked by names, but those
abstract ideas in the mind; which are, as it were, the bonds between
particular things that exist, and the names they are to be ranked under?
And when general names have any connexion with particular beings, these
abstract ideas are the medium that unites them: so that the essences of
species, as distinguished and denominated by us, neither are nor can
be anything but those precise abstract ideas we have in our minds. And
therefore the supposed real essences of substances, if different from
our abstract ideas, cannot be the essences of the species WE rank
things into. For two species may be one, as rationally as two different
essences be the essence of one species: and I demand what are the
alterations [which] may, or may not be made in a HORSE or LEAD, without
making either of them to be of another species? In determining the
species of things by OUR abstract ideas, this is easy to resolve: but if
any one will regulate himself herein by supposed REAL essences, he will
I suppose, be at a loss: and he will never be able to know when anything
precisely ceases to be of the species of a HORSE or LEAD.


14. Each distinct abstract Idea is a distinct Essence.

Nor will any one wonder that I say these essences, or abstract ideas
(which are the measures of name, and the boundaries of species) are