"Central to the contemporary dispute over 'naturalizing epistemology' is the question of the continuity of epistemology with science, i.e., how far purely descriptive, psychological matters can or should inform the traditional evaluative epistemological enterprise. Thus all parties tend to agree that the distinction between psychology and epistemology corresponds to a firm fact/value distinction. This is something Reid denies with respect to the first principles of common sense: while insisting on the continuity of epistemology with the rest of science, he does not wish to derive an 'ought' from an 'is', nor to reduce the epistemological to the psychological. His view is that the first principles are constitutive principles, hence that they are simultaneously descriptive and prescriptive, and thus that with regard to them there is in this sense simply no fact/value gap to be bridged."
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