which Kant himself applied in his Prolegomena, the problem of Kant's Critique of Reason may be thus formulated: What presuppositions must I postulate if thought is to be regarded as means to an end, at least to the intellectual end of understanding. We are confined by similar lines of thought in recent philosophical literature from various quarters.
Noted natural scientists, reflecting upon the principles of their science, have observed that the definitions of the concepts and the presuppositions of science must seek their justification in the fact that they furnish the possibility of an intellectual elaboration and interpretation of the facts. Their necessity rests upon this fact alone, which however is not apodictic until the possibility of other concepts and presuppositions than those now in use, serving the same purpose quite as well, is excluded. Maxwell expressed this view in 1885, Ernst Mach in 1863.
Avenarius, from 1876 onward, developed his natural history of the problems from a purely psychological viewpoint: because of the fact that consciousness does not possess an infinite ideational capacity it is obliged to introduce economy into its thought, which gives rise to the problem of construing what is given in experience with the least possible subjective addition.
Pragmatism so called shows a similar tendency. This term was first introduced by the American mathematician and philosopher Peirce (1878), and afterwards appropriated by his fellow countryman, William James (1898), who combines it with a whole psychological and philosophical system. Pragmatism establishes the concepts and presuppositions by the practical consequences involved in the experiences to which they lead. If we
