y must be assumed, whose attribute is freedom.
Proof. All so-called natural causes are effects of preceding causes,
forming a regressive series of indefinite extent, with no first
beginning. So we never arrive at an adequate cause of any phenomenon.
Yet natural law has for its central demand that nothing shall happen
without such a cause.

Antithesis. All events in the universe occur under the exclusive
operation of natural laws, and there is no such thing as freedom. Proof.
The idea of a free cause is an absurdity. For it contradicts the very
law of causation itself, which demands that every event shall be in
orderly sequence with some preceding event. Now, free causation is such
an event, being the active beginning of a series of phenomena. Yet the
action of the supposed free cause must be imagined as independent of all
connection with any previous event. It is without law or reason, and
would be the blind realisation of confusion and lawlessness. Therefore
transcendental freedom is a violation of the law of causation, and is in
conflict with all experience. We must of necessity acquiesce in the
explanation of all phenomena by the operation of natural law, and thus
transcendental freedom must be pronounced a fallacy.

FOURTH ANTINOMY. Thesis. Some form of absolutely necessary existence
belongs to the world, whether as its part or as its cause. Proof.
Phenomenal existence is serial, mutable, consistent. Every event is
contingent upon a preceding condition. The conditioned pre-supposes, for
its complete explanation, the unconditioned. The whole of past time,
since it contains the whole of all past conditions, must of necessity
contain the unconditioned or also "absolutely necessary."

Antithesis. There is no absolutely necessary existence, whether in the
world as its part, or outside of it as its cause. Proof. Of
unconditionally necessary existence within the world there can be none.
The assumption of a first unconditioned link in the chain of cosmical
conditions is self-contradictory. For such link or cause, being in time,
must be subject to the law of all temporal existence, and so be
determined--contrary to the original assumption--by another link or
cause before it.

The supposition of an absolutely necessary cause of the world, existing
without the world, also destroys itself. For, being outside the world,
it is not in time. And yet, to act as a cause, it must be in time. This
supposition is therefore absurd.