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| Roy Wood Sellars |
Roy Wood Sellars, the American critical realist, taught philosophy at the University of Michigan. Although he was never as well known outside philosophical circles as some of his contemporaries, after the publication of his first book, Critical Realism, in 1916, Sellars maintained a substantial reputation among his fellow philosophers as a vigorously independent thinker. His thought was rigorous and critical; he never yielded to the fashionable movements of the day but steadfastly pursued his own original insights into basic philosophical problems.
The core of Sellars’s philosophy is epistemological. He is concerned with showing that the critical realism of the philosopher is related to the “natural realism” of the “plain man.” The philosopher reflects on the plain man’s uncritical view of knowledge, which he clarifies and refines so that it is philosophically justifiable, but he does not vitiate its essential insistence upon the independence of the object of knowledge.
The most significant element in Sellars’s vindication of realism is his revision of the theory of perception, which he describes as a process of interpretation of sensa, as mediated by factors both external and internal to the perceiving subject.
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| Critical Realism |
This view of perception avoids both the simplistic claim of natural realism that things reveal themselves directly in perception and the subjectivist claim that the objects of perception are ideas rather than things. Knowledge, too, is a complex process and occurs at various levels of complication.
Its ultimate biological source is to be found in the adjustment of the organism to its environment; its ultimate outreach is in scientific knowledge, which replaces the relativity of individual perspectives by close approximations to exact measurement. Whether on the implicit organic level or on the highly explicit and self-critical scientific level, we know that we know when the content of our beliefs corresponds to the externally observed state of affairs.
Working from this epistemological position, Sellars developed an evolutionary cosmology and a materialistic ontology, carrying on his insight that there are levels, or “gradients,” of being. Even the higher levels like life and mind, which emerge under most favorable conditions, are, however, physical systems.
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| the Humanist Manifesto |
Sellars’s materialism is nonreductive, but he insists that “life is not a nonnatural force coming from outside, but a term for the new capacities of which nature has found itself capable.” On the valuational side, Sellars argues from these positions to a humanistic theory of ethics and religion (he was one of the major contributors to the composition of the Humanist Manifesto of 1933) and to a politics of democratic socialism.