An introductory text-book of logic - Mellone, Sydney - Rare Books at ...

22 THE NAME, THE TERM, THE CONCEPT,
between them the universe of discourse, not the whole
universe of thought and existence. Thus,
"
not
"
white are contradictories in the world of colour;
and only those things which may have colour must be either
the one or the other. Sometimes we have a pair of names
"white" and
which themselves denote a particular sphere ; "British" and
"
"
Alien are limited to the sphere of human beings, and
within that sphere would be considered as contradictories, if
the view to which we have referred is to be accepted. But
it is preferable to keep to the older view and take the
"
con
"
tradictory in the widest possible sense, as this brings out
more forcibly the nature of pure logical contradiction. We
may interpret the pure contradictory in such a way that it
involves no logical absurdity. We need not, for instance,
"
"
use the name not-man as meaning all things together
which are not man, that is, we need not use it collectively.
We may use it distributively, as being applicable to any
which is not man it is exactly therefore what Aristotle
thing :
called it an indefinite name. If we try to express its
denotation, we must think, not of "a chaotic mass of the
"
"
most different things together, but of either this, or this,
or this, or ..." and so on indefinitely, through everything
which is not denoted by the original term. Those who
take the narrower view of contradictory names, explain
contrary terms as representing opposites without exhausting
"
between them the particular sphere of reference or universe
and
"
"
"
of discourse ; thus, white
the world of colour.
"
"
black are contraries in
According to our view, contraries do not exhaust
between them the universe of thought and existence;
and the opposition which they express is of various kinds.
The type to which Aristotle restricts the name of
"
"
contrary opposition is the relation of
stand furthest apart among those of the same genus
"
things which
(Categories, ch. vi., and elsewhere); as "white" and
"
black,"
"
"
virtuous
and
"
vicious." A more general
case is incompatibility, i.e., the opposition of qualities
which cannot be possessed by the^same thing in the
"