 Left relatively untouched by historicist philosophers during the Battle of the Big Systems was the internal/external distinction. The philosophers, consonant with traditional sociology of science (e.g., Merton 1973) and sociology of knowledge more generally, defended a kind of “inertial principle” (Fuller 1989: xiii et passim): social and psychological factors such as economic and political interests and psychological dispositions should be brought into play only to explain deviation from the rational path. This distinction began to erode already in Kuhn, who stressed the social factors internal to the organization of science itself: science education, the strong role of scientific communities with their distinctive cultures, etc. (See also Lakatos on comprehensive theories of rationality that can turn apparent external considerations into internal ones, and Hull 1988 on career advancement.)