PROOF.
Let it be supposed, that there is no other kind of causality than
that according to the laws of nature. Consequently, everything that
happens presupposes a previous condition, which it follows with
absolute certainty, in conformity with a rule. But this previous
condition must itself be something that has happened (that has
arisen in time, as it did not exist before), for, if it has always
been in existence, its consequence or effect would not thus
originate for the first time, but
would likewise have always
existed. The causality, therefore, of a cause, whereby something
happens, is itself a thing that has
happened. Now this again
presupposes, in conformity with the law of nature, a previous
condition and its causality, and this another anterior to the
former, and so on. If, then, everything happens solely in accordance
with the laws of nature, there cannot be any real first beginning of
things, but only a subaltern or comparative beginning. There cannot,
therefore, be a completeness of series on the side of the causes which
originate the one from the other. But the law of nature is that
nothing can happen without a sufficient
a priori determined cause. The
proposition therefore— if all causality is possible only in accordance
with the laws of nature— is, when stated in this unlimited and general
manner, self—contradictory. It follows that this cannot be the only
kind of causality.
From what has been said, it follows that a causality must be
admitted, by means of which something happens, without its cause being
determined according to necessary laws by some other cause
preceding. That is to say, there must exist an absolute spontaneity of
cause, which of itself originates a series of phenomena which proceeds
according to natural laws— consequently transcendental freedom,
without which even in the course of nature the succession of phenomena
on the side of causes is never complete.
