Rather, we must infer the extent to which the human rational faculties can reach the object of "things-in-themselves" by our observations of the manifestations of those things that can be perceived via the physical senses, that is, of phenomena, and by ordering these perceptions in the mind help infer the validity of our perceptions to the rational categories used to understand them in a rational system. This rational system (transcendental analytic), being the categories of the understanding as free from empirical contingency.

According