Kant, then, developed transcendental idealism as an alternative to realism, on the one hand, and skepticism, on the other. His thinking can be labeled as idealism because he held that we know reality through the capacities of the mind and it is transcendental because the categories through which we know are given outside our direct experience. In this way, Kant provided a sophisticated justification for the scientific method.

(Stacey, 2000, pp 21)

Stacey, 2007, pp 31-31