Now if we can demonstrate that even our purest a priori intuitions provide no cognition except insofar as they contain the sort of combination of the manifold that makes possible a thorough going synthesis of reproduction, then this synthesis of the imagination would be grounded even prior to all experience on a priori principles,a and one must assume a pure transcendental synthesis of this power, which grounds even the possibility of all experience (as that which the reproducibility of the appearances necessarily presupposes).