“When I say: I think, I act, etc., then either the word I is applied falsely, or I am free. Were I not free, then I could not say: I do it, but rather I would have to say: I feel in me a desire to do, which someone has aroused in me. But when I say: I do it, that means spontaneity in the transcendental sense. But now I am conscious to myself that I can say: I do; therefore I am conscious of no determination in me, and thus I act absolutely freely.” — Immanuel Kant

“By freedom in the cosmological sense … I understand the power of beginning a state from itself, the causality of which does not in turn stand under another cause determining it in time in accordance with the law of nature. It is especially noteworthy that it is this transcendental idea of freedom on which the practical concept of freedom is grounded, and the former constitutes the real moment of the difficulties in the latter, which have long surrounded the question of its possibility.” — Immanuel Kant

Freedom (Existenz) is “transcendental” because transcendental subjectivity consists of two forever mutually conditioning aspects: freewill and causal structures ("karmic seeds", in Yogācāra terms; "elementary particles", in modern scientific terms).

Transcendental freedom can't be observed as a phenomenal object, it can only be lived. It can neither be proved nor disproved. It can only be a matter of faith.

Within the framework of individual existence there is no freedom without causal structures, for absolute freedom terminates the individual existence of transcendental subjectivity in the absolute perspective of Consciousness — in transcendent consciousness-in-itself, the nondual Light of mystical/transpersonal experiences. Freewill is never absolutely free. Absolute freedom is not freedom, it is Absolute.

Freedom is emanation, becoming. Through freedom and causal structures of transcendental subjectivity the Light becomes everything we know as ourselves—transcendental and empirical subjects—and the empirical world of intersubjective phenomena.

“Freedom is a self-bestowal by Transcendence. This freedom is not expedience, not obedience to a calculated duty, not forced activity, but a will detached from all compulsion, and this will is transcendent necessity.” — Karl Jaspers