World Hypotheses: A Study in Evidence, by Stephen C. Pepper (1942), presents four relatively adequate world hypotheses (or world views or conceptual systems) in terms of their root metaphors: formism (similarity), mechanism (machine), contextualism (historical act), and organicism (living system).
In World Hypotheses, Pepper demonstrates the error of logical positivism, that there is no such thing as data free from interpretation, and that root metaphors are necessary in epistemology. In other words, objectivity is a myth because there is no such thing as pure, objective fact. Consequently, an analysis is necessary to understand how to interpret these 'facts.' Pepper does so by developing the "[root metaphor method, ...] and outlines what he considers to be four basically adequate world hypotheses (world views or conceptual systems): formism, mechanism, contextualism, and organicism." He identifies the strengths and weaknesses of each of the world hypotheses as well as the paradoxical and sometimes mystifying effects of the effort to synthesize them.[1]