What is "transcendental apperception"

In philosophy, Kantian transcendental apperception is that which Immanuel Kant thinks makes experience possible. It is where the self and the world come together.

Transcendental apperception is the uniting and building of coherent consciousness out of different elementary inner experiences (differing in both time and topic, but all belonging to self-consciousness). E.g. the experience of "passing of time" relies on this transcendental unity of apperception, according to Kant.

There are six steps to transcendental apperception:

1. All experience is the succession of a variety of contents (an idea taken from David Hume).
2. To be experienced at all, the successive data must be combined or held together in a unity for consciousness.
3. Unity of experience therefore implies a unity of self.
4. The unity of self is as much an object of experience as anything is.
5. Therefore, experience both of the self and its objects rests on acts of synthesis that, because they are the conditions of any experience, are not themselves experienced.
6. These prior syntheses are made possible by the categories. Categories allow us to synthesize the self and the objects.

The term was later adapted in psychology by Johann Friedrich Herbart, see Apperception.