The monograph examines the formation and development of two leading trends in the philosophy of the New Age - empiricism and rationalism, as well as the first attempt to synthesize them by Kant. The author convincingly demonstrates that a genuine solution to the problem cannot be found on the path of a priori. At the same time, the author reveals historically valuable results that the first attempt to synthesize empiricism and rationalism reveals to the historian of philosophy, and the direct influence that Kant had on classical German philosophy in terms of solving this problem.