Unlike pure theorists, we shall not assume at the outset that rational behavior exists or that rational behavior constitutes the topic of economic analysis. We shall study economic behavior as we find it. In describing and classifying different reactions, as well as the circumstances that elicit them, we shall raise the question whether and in what sense certain reactions may be called rational. After having answered that question and thus defined our terms, we shall study the fundamental problem: Under what conditions do more and under what conditions do less rational forms of behavior occur?

George Katona (1951). Psychological Analysis of Economic Behavior. McGraw-Hill, New York. p. 16; as cited in: Erik Angner and George Loewenstein. "Behavior economics," in: Philosophy of Economics, (2012), p. 657