KANT'S CRITIQUE OF TELEOLOGY IN BIOLOGICAL EXPLANATION

26 Kant's Reading of Biology
for in the context he is making a distinction precisely between mere
accident and the necessity of mechanical laws: "In my conceptual
scheme (Lehrverfassung) I find matter bound by certain necessary
laws" (W 1,234; Ak 1,227).
In spite of all his skepticism about the chances of giving a
mechanical explanation of a worm, Kant is forced by the structure
of his theory of the heavens to assume a mechanical origin. On
account of his cosmogonic theory, the deistic option is not open to
him. Having explained that the planets etc. arose gradually and,
consequently, that the necessary conditions for life could have
arisen only in the course of time, he has only two alternatives: either
matter has the ability to bring forth life of its own accord, or God
intervenes in the already existing world so that life is a miracle and
thus not the object of natural scientific explanation. This second
option can be discarded for reasons of principle, since it invokes the
ill-reputed deus ex machina, through which everything can be
explained without effort. As Leibniz had pointed out, such explanations
turn theology into the supplier of ad hoc hypotheses for bad
science. Furthermore, in Kant's theory God would have to intervene
again and again in the course of the world because there are very
many planets, which are all to be furnished with life but which only
achieve the conditions necessary to shelter life at different times.
Kant concludes his theory of the heavens with a speculative
chapter "On the Inhabitants of the Stars," in which he assumes that
life exists on many different celestial bodies. It may well not be
impossible, he cautions, that some planets are uninhabited, but it
would be "an absurdity" to deny that most of the planets are in fact
inhabited, in so far as the right conditions prevail or have prevailed
there. The necessary conditions arise in the course of time:
Our Earth existed perhaps for a thousand or more years before it found
itself in a position to support humans, animals, and plants. Now, the fact that
a planet arrives at this perfection a few thousand years later does not
gainsay the purpose of its existence. (W 1,378-79; Ak 1,352-53)
It should be clear that such a theory implies some kind of
original spontaneous generation as soon as the appropriate physical
conditions come about. There is no indication at all that Kant sees
any kind of problem in principle. Although he does not in fact explicitly
commit himself to a belief in the law-like occurrence of spontaneous
generation – as, for instance, Buffon was to do only a few