Not very long ago it was extremely fashionable among official men of learning to say that Marx had really produced nothing new in the philosophical sphere. Such a well-known philosopher as Wilhelm Wundt in
his Introduction to Philosophy wrote "This lack of clarity in its metaphysical premises (i.e. of Marxism. N.B.) has a comprehensible basis in the fact that practical questions alone interest sociological materialism. Therefore the system does not even possess the necessary
theoretical foundation, which it openly leaves to physiological materialism to work out."1)
…