As a potential fifth world hypothesis from Stephen C. Pepper, a root metaphor of the _purposive act_ was proposed for _selectivism_.
Ties to the purposive behaviorism of [Edward C. Tolman](https://www.britannica.com/biography/Edward-C-Tolman) are described in a [2004 manuscript, Bill J. Harrell](https://web.archive.org/web/20070518115707/http://people.sunyit.edu:80/~harrell/Pepper/pep_wh-select01.htm):
> [207] Pepper argues that it was only recently (1961) that the structure of the purposive act had been sufficiently analyzed that it showed promise as a point of departure for a world hypothesis. > * Of course, teleological world theories have been proposed from at least the time of Aristotle, but the new analysis of purpose is not necessarily teleological in the sense that it assumes history and nature are headed toward some cosmic goal. > > "All it requires is that the structural character of purposive activity find full embodiment in this theory and that all interpretations be made in terms derivable form this structural character." (CQ, p. 15) > The basic description of purposive structure is derived from Edward C. Tolman, a self-proclaimed "rat psychologist." > * It is important to make this as explicit as possible because the theoretical gravity of purposive behavior is widely recognized, but what is specifically meant by the purposive act is distinctly controversial. > * In sociology, a view apparently close to that of Tolman’s has been generally and, in my opinion, rightly rejected since the 1930’s. > * Unfortunately, a more fruitful description of the rudimentary attributes of behavior such as Tolman’s has also been discarded. > Though Pepper himself did not succeed in effectively applying this world hypothesis to sociological questions, the major task of this work is to illustrate how it can be done with benefit to social theory. > * Tolman’s analysis of the purposive act amounts to the root metaphor of selectivism and, I believe, moves selectivism in a more fruitful direction than most other theories which place goal oriented behavior at the center of its conceptual framework.
The question of whether selectivism was a new world hypothesis or a refinement of Contextualism is discussed in a [2004 manuscript, where Bill J. Harrell](https://web.archive.org/web/20070518115707/http://people.sunyit.edu:80/~harrell/Pepper/pep_wh-select01.htm) wrote of Pepper:
> [204] He considered this study a sequel to _World Hypotheses_ but did not believe it supplanted the earlier work. > * The four world hypotheses were basically adequate and he still could not identify a cognitively responsible means of choosing one over the other. > Selectivism was a fifth and new world theory or possibly a radical revision of one of the original hypothesis, contextualism. > * This new world hypothesis has the same cognitive status as the others and bears the same relationship to the others as they do one to the other. > * That said, it is fairly apparent that Pepper was convinced that selectivism handled many of the problems the others could not resolve. > * He spends a great deal more time in this book discussing how experience interpreted within the other world hypotheses would be interpreted by selectivism and how the latter interpretations avoid the contradictions and paradoxical dilemmas of the other theories. > * It is understandable, therefore, why some have argued(myself included)that selectivism was not an independent world hypothesis but a meta-theory within which the categories of the other perspectives could be incorporated and explained.