disguise, what is important for other cases. We should distinguish sharply between our theoretical conceptions of phenomena and that which we observe. The theoretical conceptions of physics light-waves, molecules, atoms, and energy must be regarded as mere helps or expedients to facilitate our viewing things. Even within the domain of physics the greatest care must be exercised in transferring theories from one department to another, and above all more instruction is not to be expected from a theory than from the facts themselves. Much greater confusion is produced by the direct transference of theories, methods, and inquiries that are legitimate in physics into the field of psychology. The entire theory of the psychological origin of the "external" world by the projection of sensations outwards is founded on a mistaken transference of a physically formulated inquiry into the province of psychology. The artificial and unnecessary dualism of feeling and motion has arisen by the improper formulation of the questions involved. Every physical notion is nothing more than a definite connection of sensory elements. In the sensory sphere of consciousness everything is at once physical and psychical. There is, therefore, no opposition of physical and psychical, no duality, but simply identity.
The term "thing- in-itself" in the sense of a thing as it is independent of sensibility, would better be called "the objective thing," and we shall so call it, to distinguish it from Kant's thing-in-itself. The idea of a thing-in-itself has found support in a mistaken conception of the unity of certain things, especially of organisms. The mind is a product of the world; it is a system of symbols representing the things of the world and their relations, including such possible relations as are worthy of aspiring for. The idea of a thing-in-itself, and the unknowableness of the thing-in-itself are the basis of all agnosticism. Neither nominalism or realism are right, but if properly interpreted they are complementary: "universals are real," says the realists, i.e. the forms and relations of things are actualities; "universals are laws," says the nominalists, i.e. the relations and forms in which we describe the world are mental symbols. Positivism, i.e. the representation of facts without any admixture of theory or mythology, is an ideal which in its purity perhaps will never be realized. Science cannot dispense with hypotheses, with theories, with mythology. The world is not rigid being but activity, not absolute existence but a system of changing relations, not an abstract Sein but a concrete Wirklichkeit — constant working of
