KANT'S CRITIQUE OF TELEOLOGY IN BIOLOGICAL EXPLANATION

Infinite Judgments 73
judgments stand merely in the relation of contrariety. 3 1 For
instance, an inanimate stone is neither mortal nor immortal (nonmortal).
On the other hand, the soul (anima) must be either mortal
or immortal, since it is analytically true — at least in our
conceptual system — that the soul is animate.
The main function of infinite or indefinite terms is not in the
logic of inference but in the logic of terms or categories, where it is
used for definitional division. Any genus can be divided neatly into
two species by distinguishing one species and negating it within the
genus; for instance, all mammals are either marsupials or nonmarsupials.
In this case of course being a non-marsupial presupposes
that one is a mammal. A predicate and its "infinite" negation
are two mutually exclusive species which exhaust a genus, or in
Strawson's terminology, they are two predicates which exhaust a
given "range of incompatibility." 32 Thus if a subject falls under the
range of incompatibility of being a mammal, it must either be marsupial
or non-marsupial; if it falls under the genus of colored
things, it must be blue or non-blue. The Law of the Excluded Middle
holds only under such assumptions, when dealing with this kind of
negation. Assuming the soul is animate (which is analytic), then it
is either mortal or immortal; if the soul were the sort of thing that is
not alive, then it would be neither mortal nor immortal just as
stones, prime numbers, and truth tables are neither the one nor the
31 Kant formulates the law of non-contradiction as follows: "No thing may be
ascribed a predicate that contradicts it." (B*190, cf. also Ak 2,294; W 1,765). By
this Kant means that no thing may be ascribed a predicate whose opposite is
contained in the concept of the thing; for instance, "No unlearned person is
learned." In such a formulation the restriction "at the same time" is unnecessary.
In his discussion of the law of non-contradiction, Kant separates a predicate
from the concept of the subject and then attributes both this predicate and its
opposite to the subject at the same time. In this case the predicate does not contradict
the subject (as the law of non-contradiction is said to demand) but rather only the
other predicate: The person is learned; the person is unlearned. "The misunderstanding
results from our first of all separating a predicate of a thing from the
concept of that thing, and afterwards connecting this predicate with its opposite —
a procedure which never occasions a contradiction with the subject but only with
the predicate which has been synthetically connected with that subject, and even
then only when both predicates are affirmed at one and the same time" (B192).
The formulation presupposes that the person belongs to the genus of things that are
either learned or unlearned. On the idiosyncracies of Kant's version of the law of
non-contradiction in general, cf. Wolff, "Der Begriff des Widerspruchs in der
'Kritik der reinen Vernunft'."
32 Strawson, Introduction to Logical Theory, chap. 1.