fference, whereby we know and distinguish them one from
another, consisting only in the different collection of simple ideas, to
which we have given those different names.

39. How Genera and Species are related to naming.

How much the making of species and genera is in order to general names;
and how much general names are necessary, if not to the being, yet at
least to the completing of a species, and making it pass for such, will
appear, besides what has been said above concerning ice and water, in
a very familiar example. A silent and a striking watch are but one
species, to those who have but one name for them: but he that has the
name WATCH for one, and CLOCK for the other, and distinct complex ideas
to which those names belong, to HIM they are different species. It
will be said perhaps, that the inward contrivance and constitution is
different between these two, which the watchmaker has a clear idea of.
And yet it is plain they are but one species to him, when he has but one
name for them. For what is sufficient in the inward contrivance to make
a new species? There are some watches that are made with four wheels,
others with five; is this a specific difference to the workman? Some
have strings and physics, and others none; some have the balance loose,
and others regulated by a spiral spring, and others by hogs' bristles.
Are any or all of these enough to make a specific difference to
the workman, that knows each of these and several other different
contrivances in the internal constitutions of watches? It is certain
each of these hath a real difference from the rest; but whether it be an
essential, a specific difference or no, relates only to the complex idea
to which the name watch is given: as long as they all agree in the idea
which that name stands for, and that name does not as a generical name
comprehend different species under it, they are not essentially nor
specifically different. But if any one will make minuter divisions, from
differences that he knows in the internal frame of watches, and to such
precise complex ideas give names that shall prevail; they will then be
new species, to them who have those ideas with names to them, and can by
those differences distinguish watches into these several sorts; and
then WATCH will be a generical name. But yet they would be no distinct
species to men ignorant of clock-work, and the inward contrivances of
watches, who had no other idea but the outward shape an