The distinctive mark of socialism is the oneness and indivisibility of the will directing all production activities within the whole social [p. 706] system.

In order to appraise adequately the idea that the differential equations of mathematical economics could be utilized for socialist economic calculation, we must remember what these equations really mean.

ONE* OF THE UNHAPPY CASUALTIES of World War I, it seems, was the old-fashioned treatise on economic “principles.” Before World War I, the standard method, both of presenting and advancing economic thought, was to write a disquisition setting forth one’s vision of the corpus of economic science.

THE DISTINCTIVE AND CRUCIAL FEATURE in the study of man is the concept of action.1 Human action is defined simply as purposeful behavior. It is therefore sharply distinguishable from those observed movements which, from the point of view of man, are not purposeful.

The first truth to be discovered about human action is that it can be undertaken only by individual “actors.” Only individuals have ends and can act to attain them. There are no such things as ends of or actions by “groups,” “collectives,” or “States,” which do not take place as actions by various specific individuals. “Societies” or “groups” have no independent existence aside from the actions of their individual members.

The means to satisfy man’s wants are called goods.