transcendental ideality

is the idea that as soon as we look at something like space, subtracting out sensual experience one by one (sight, sound, smell, taste, or anything bodily), it becomes something that belongs to things in themselves.

We maintain, therefore, the empirical reality of space in regard to all possible external experience, although we must admit its transcendental ideality... in other words, that it is nothing, so soon as we withdraw the condition upon which the possibility of all experience depends and look upon space as something that belongs to things in themselves. (CPR 41)

transcendental ideality, n.Definitions

transcendental ideality