KANT'S CRITIQUE OF TELEOLOGY IN BIOLOGICAL EXPLANATION

Course of the Argument 85
in some detail if the arguments for the resolution of the antinomies
are to become intelligible. I shall therefore now take up Kant's analysis
of the concept of infinity as presented in the resolution of the
First Antinomy (beginning/boundary of the world).
After showing the formal route to a resolution of the antinomies
in the digression on Zeno by indicating that a third possibility
exists, i.e. by showing that thesis and antithesis are logically
incompatible but not contradictory opposites, Kant takes up the question
of whether the cosmological ideas can be salvaged if presented
in a new form. If the idea of reason concerning the totality of the
series of phenomena is not misunderstood as a concept of the understanding,
but merely taken as a rule — to pursue the series ever farther,
without presupposing that the regress in the series has
already been completed —, then the idea can be used as a "regulative
principle of reason." In this manner the completion of the
series of conditions is not "given" but "set as a task" (B536). However,
the point is not that thesis and antithesis are transformed into
regulative principles, but that the idea of reason behind them both
should be used only regulatively:
The principle of reason is thus properly only a rule, prescribing a regress in
the series of the conditions of given appearances, and forbidding it to bring
the regress to a close by treating anything at which it may arrive as
absolutely unconditioned. (B536-7)
Here it is clear that at least the thesis position with its finite empirical
unconditioned (world, atoms, etc.) must prove to be false, "for the
absolutely unconditioned is not to be met with in experience" (B538).
It must however still be shown that there is an alternative to the
infinite series of the antithesis.
At the beginning of his presentation of the antinomies Kant
distinguished between progressive and regressive synthesis, and in
the course of the argument he develops a highly stylized terminology
to keep these two kinds of series distinct. A progress proceeds from a
given phenomenon (as condition) to what it conditions, e.g. the
series of descendants of a given pair of parents (B539). A regress
proceeds from a given conditioned phenomenon to its condition, e.g.
from a person now living back through the series of his or her
ancestors. Although it is only the regress that leads to dialectical
problems, the progress must nonetheless be taken into consideration
in order to make sense of the special problems of the "mathe-