In his 1942 book World Hypotheses: A Study in Evidence, philosopher Stephen Pepper noted that philosophical systems tend to cluster around a few distinct "world hypotheses" or "world views." Each world view is characterized by a distinctive underlying root metaphor and truth criterion. Root metaphors are based on seemingly well-understood, common-sense, everyday objects or ideas, and serve as the basic analogy by which an analyst attempts to understand the world. Truth criteria are inextricably linked to their root metaphors, and provide the basis for evaluating the validity of analyses. While the details of Pepper's analysis are open to debate, his framework can prove very useful for revealing the essential components, assumptions, and concerns of different discourse communities. Pepper identifies only four "relatively adequate" world hypotheses, with adequacy determined by the world view’s degree of precision and scope. Precision refers to the number of ways a particular phenomenon can be explained by a world view’s concepts (the fewer, the better), and scope refers to the number of phenomena that can be explained using those concepts (the more, the better). All world hypotheses strive to achieve complete scope with absolute precision, but none fully reach this ideal. These four world views, however, come the closest: formism, mechanism, contextualism, and organicism. The vision of psychology represented on this website is based on contextualism. It is a world view in which any event is interpreted as an ongoing act inseparable from its current and historical context and in which a radically functional approach to truth and meaning is adopted. These two aspects represent contextualism’s root metaphor and truth criterion, respectively. Contextualism has its roots in philosophical pragmatism, and is also closely related to the view known as selectionism. To learn more about contextualism, clink on a link below.