John D. Black

Scope and Method in Agricultural Economics Research: A Reply

more mature sciences if one reads their history and progress aright. Second, when a model is formulated it is always necessary to introduce two kinds of additional presuppositions: (a) Since the model is only a piece of theory lifted out of the general body of abstract relationships making up theory, in taking it out of that setting the connecting parts cannot be left merely open and dangling but must be given an exact logical status which entails the determination of some form of presupposition of which ceteris paribus is an example, used all too often when wholly inappropriate. (b) In adapting the model to reality, in addition to the difficulty in concepts already referred to, it invariably becomes necessary to extend, refine, or compromise certain aspects of the pure model which again makes it necessary to introduce presuppositions. The temporal nature of the economic activities to be analyzed is one of the major requirements of reality that must be taken into account in this connection. Finally, the search for constants which are concrete and which will serve as economic bench marks has become shrouded in a mythology like the legends of the Holy Grail. Every research worker is supposedly devoted to this search. If it is true it is nonsense-at best an enjoyable illusion. However, it probably is not nearly as prevalent as, for instance, the student of theory may suppose. The necessity of recognizing the limitations which are enforced by the presuppositions under which both concreteness and the temporal element are introduced, and thus the setting in which the facts were established and analyzed. is usually considered.