29. Our nominal essences of substances usually consist of a few obvious qualities observed in things.
Secondly,
Though the mind of man, in making its complex ideas of substances, never puts any together that do not really, or
are not supposed to, co-exist; and so it truly borrows that union from nature: yet the number it combines depends
upon the various care, industry, or fancy of him that makes it. Men generally content themselves with some few
sensible obvious qualities; and often, if not always, leave out others as material and as firmly united as those that
they take. Of sensible substances there are two sorts: one of organized bodies, which are propagated by seed; and
in these the shape is that which to us is the leading quality, and most characteristical part, that determines the
species. And therefore in vegetables and animals, an extended solid substance of such a certain figure usually
serves the turn. For however some men seem to prize their definition of animal rationale, yet should there a
creature be found that had language and reason, but partaked not of the usual shape of a man, I believe it would
hardly pass for a man, how much soever it were animal rationale. And if Balaam's ass had all his life discoursed
as rationally as he did once with his master, I doubt yet whether any one would have thought him worthy the
name man, or allowed him to be of the same species with himself. As in vegetables and animals it is the shape, so
in most other bodies, not propagated by seed, it is the colour we must fix on, and are most led by. Thus where we
find the colour of gold, we are apt to imagine all the other qualities comprehended in our complex idea to be there
also: and we commonly take these two obvious qualities, viz., shape and colour, for so presumptive ideas of
several species, that in a good picture, we readily say, this is a lion, and that a rose; this is a gold, and that a silver
goblet, only by the different figures and colours represented to the eye by the pencil.
