species; but each colour, white, black or yellow, is separable from it
under different climatic conditions; whilst tigers are everywhere
coloured and striped in much the same way; so that we may consider their
colouring as inseparable, in spite of exceptional specimens black or
white or clouded.

The same distinction may be drawn between accidents. 'Inhabiting Asia'
is an Inseparable Accident of tiger, but a Separable Accident of lion.
Even the occasional characteristics and occupations of individuals are
sometimes called separable accidents of the species; as, of man, being
colour-blind, carpentering, or running.

A proprium in the original signification of the term [Greek: hidion] was
peculiar to a species, never found with any other, and was therefore
convertible with the subject; but this restriction is no longer insisted on.

Sec. 9. Any predication of a genus, difference or definition, is a verbal,
analytic, or essential proposition: and any predication of a proprium or
accident, is a real, synthetic, or accidental proposition (chap. v. Sec.
6). A proposition is called verbal or analytic when the predicate is a
part, or the whole, of the meaning of the subject; and the subject being
species, a genus or difference is part, and a definition is the whole,
of its meaning or connotation. Hence such a proposition has also been
called explicative. Again, a proposition is called real or synthetic
when the predicate is no part of the meaning of the subject; and, the
subject being species, a proprium or accident is no part of its meaning
or connotation. Hence such a proposition has been called ampliative.

As to Essential and Accidental, these terms are derived from the
doctrine of Realism. Realists maintain that the essence of a thing, or
that which makes a thing to be what (or of what kind) it is, also makes
everything else of the same kind to be what it is. The essence, they
say, is not proper to each thing or separately inherent in it, but is an
'Universal' common to all things of that kind. Some hold that the
universal nature of things of any kind is an Idea existing (apart from
the things) in the intelligible world, invisible to mortal eye and only
accessible to thought; whence the Idea is called a noumenon: that only
the Idea is truly real, and that the things (say, trees, bedsteads and
cities) which appear to us in sense-perception, and which therefore are
called phenomena, only exist by participating in, or imita