Werner Sombart Wishes to Trace Back the Opposition Between the Marxian System and the Austrian School System to a Dispute About Method

This leads me to a last point on which I must touch in regard to Sombart. Sombart wishes to trace back the opposition which exists between the Marxian system on the one side, and the adverse theoretic systems—especially of the so-called Austrian economists—on the other, to a dispute about method. Marx, he says, represents an extreme objectivity. We others represent a subjectivity which runs into psychology. Marx does not trace out the motives which determine individual subjects as economic agents in their mode of action, but he seeks the objective factors, the "economic conditions," which are independent of the will, and, I may add, often also of the knowledge, of the individual. He seeks to discover "what goes on beyond the control of the individual by the power of relations which are independent of him." We, on the contrary, " try to explain the processes of economic life in the last resort by a reference to the mind of the economic subject," and "plant the laws of economic life on a psychological basis."

--Eugen von Böhm-Bawerk, Karl Marx and the Close of His System: A Criticism, trans. Alice M. Macdonald (London: T. Fisher Unwin, 1898), 211-212.