Transcendental Idealism

Lore & Background

Kant's doctrine restricts the scope of our cognition to appearances given to our sensibility and denies that we can possess cognition of things as they are in themselves, i.e. things as they are independently of how we experience them through our cognitive faculties. Kant first described it in his Critique of Pure Reason and distinguished his view from contemporary views of realism and idealism, but it remains the case that philosophers do not agree on how sharply Kant differs from each of these positions. Transcendental idealism is associated, if not identified, with the formalistic idealism Kant discusses in his Prolegomena to any Future Metaphysics, although recent research has tended to dispute this identification. Transcendental idealism was also adopted as a label by the subsequent German philosophers Johann Gottlieb Fichte and Friedrich Wilhelm Joseph von Schelling, Arthur Schopenhauer, and in the early 20th century by Edmund Husserl in the novel form of transcendental-phenomenological idealism.

In Their Own Story

Arthur Schopenhauer takes Kant's transcendental idealism as the starting point for his own philosophy, which he presents in The World as Will and Representation. Schopenhauer described transcendental idealism briefly as a "distinction between the phenomenon and the thing in itself", and a recognition that only the phenomenon is accessible to us because "we know neither ourselves nor things as they are in themselves, but merely as they appear." In volume 1 of the Parerga and Paralipomena ("Fragments for the History of Philosophy"), Schopenhauer writes: "Now in the first place, Kant understands by transcendental the recognition of the a priori and thus merely formal element in our knowledge as such, in other words, the insight that such knowledge is independent of experience, indeed prescribes for this even the unalterable rule whereby it must turn out." Further on in §13, Schopenhauer says of Kant's doctrine of the ideality of space and time: "Before Kant, it may be said, we were in time; now time is in us. In the first case, time is real and, like everything lying in time, we are consumed by it. In the second case, time is ideal; it lies within us."

Reader's Guide

In The Bounds of Sense, P. F. Strawson suggests a reading of Kant's first Critique that, once accepted, forces rejection of most of the original arguments, including transcendental idealism. Strawson contends that, had Kant followed out the implications of all that he said, he would have seen that there were many self-contradictions implicit in the whole. Strawson views the analytic argument of the transcendental deduction as the most valuable idea in the text, and regards transcendental idealism as an unavoidable error in Kant's greatly productive system. In Strawson's traditional reading (also favored in the work of Paul Guyer and Rae Langton), the Kantian term phenomena (literally, things that can be seen—from Greek: phainomenon, "observable") refers to the world of appearances, or the world of "things" sensed.

Did You Know?

• Kant first described transcendental idealism in his Critique of Pure Reason (1781).
• Kant describes time and space as 'empirically real' but 'transcendentally ideal'.
• Arthur Schopenhauer described transcendental idealism as a 'distinction between the phenomenon and the thing in itself'.
• Schopenhauer wrote: 'Before Kant, it may be said, we were in time; now time is in us.'
• P. F. Strawson regarded transcendental idealism as an unavoidable error in Kant's system.