Advocating a sociological explanation of scientific knowledge, David Bloor protests against the adherents of the autonomy of knowledge; i.e., those who asymmetrically explain the credibility of theories in the history of science. These philosophers and historians regard the credibility of true and rational theories due to their proper reasons, while accounting for the acceptance of false or irrational beliefs by citing social causes. Bloor assumes that the credibility of all beliefs is socially influenced, and therefore considers all in need of (...) sociological explanation. To substantiate this claim, he argues that all epistemic factors that are appealed to in explaining true or rational beliefs are really social. However, this argument aligns rational entities with social factors, and thus, undermines the ground of this division. Therefore, his prior complaint of the autonomy of knowledge would be invalidated. Hence, there is a conflict between Bloor’s objection to the asymmetrical explanation of scientific theories and his account of the social construction of epistemic reasons. In this paper, we reveal this concealed conflict and attempt to suggest ways to resolve it. (shrink)