Ludwig von Mises
The Task and Scope of
the Science of Human Action
I. The Nature and Development of the Social Sciences
1. Origin in the Historical and Normative Sciences
It is in accounts of history that we find the earliest beginnings of knowledge in the sciences of human action. An epistemology that is today rejected required of the historian that he approach his subject matter without theory and simply depict the past as it was. He has to describe and portray past reality, and, it was said, he will best succeed in doing this if he views events and the sources of information about them with the least possible amount of prejudice and presupposition.
Not until very late was it realized that the historian cannot duplicate or reproduce the past; on the contrary, he interprets and recasts it, and this requires that he make use of some ideas that he must have already had before setting about his work. Even if, in the course of his work, the treatment of his material leads him to new ideas, concepts are always logically prior to the understanding of the individual, the unique, and the non-repeatable. It is impossible to speak of war and peace unless one has a definite conception of war and peace before one turns to the historical sources. Nor can one speak of causes and effects in the individual case unless one possesses a theory that treats certain connections between cause and effect as having a universal range of applicability. The reason why we accept the sentence, "The king defeated the rebels and therefore remained in power," but are not satisfied with the logically contradictory sentence, "The king defeated the rebels and therefore fell from power," is that the first conforms to our theories about the results of military victory, while the latter contradicts them.
The study of history always presupposes a measure of universally valid knowledge. This knowledge, which constitutes the conceptual tool of the historian, may sometimes seem platitudinous to one who considers it only superficially. But closer examination will more often reveal that it is the necessary consequence of a system of thought that embraces all human action and all social phenomena. For example, in using an expression such as "land hunger," "lack of land," or the like, one makes implicit reference to a theory that, if consistently thought through to its conclusion, leads to the law of diminishing returns, or in more general terms, the law of returns. For if this law did not hold, the farmer who wanted to obtain a greater net yield would not require more land; by means of an increased expenditure of labor and capital goods he would be able to obtain from even the smallest piece of tillage the same result he wanted to achieve by increasing the amount of acreage at his disposal. The size of the area available for cultivation would then be a matter of indifference to him.
However, it is not only in history and in the other sciences that make use of the conceptual tools of historical investigation that we find universally valid statements about human action. Such knowledge also constitutes the foundation of the normative sciences?ethics, the philosophy of law, and systematic jurisprudence. The primary task of political philosophy, the philosophy of law, and political science is the attainment of universally valid knowledge of social phenomena. If they have failed in this endeavor, the reason is to be sought not only in the fact that they often strayed from their goal and aimed at others, and?like the philosophy of history?instead of seeking the universally valid in the vicissitudes of particular events, began to search for the objective meaning of things. The determining factor in their failure was that from the very outset they made use of a scientifically unfruitful method: they began not with the individual and his action, but with attempts to view the totality. What they wanted to discover was not the regularity prevailing in the action of men, but the whole course of mankind's progression from its origin to the end of all things.
Psychology, in turning to the individual, found the right starting point. However, its path necessarily leads in another direction than that of the science of human action. The subject matter of the latter is action and what follows from action, whereas the subject matter of psychology is the psychic events that result in action. Economics begins at the point at which psychology leaves off.
 Cf. Rickert, Kulturwissenschaft und Naturwissenschaft (3rd ed.; T?bingen, 1915), pp. 28 ff.