Among the literature of the 1970s which enthusiastically emphasized the externalist approach to the history of science was an article by John Farley and Gerald L. Geison which has often been referred to. It gave an interpretation of the spontaneous generation debate of 1859–64 between Louis Pasteur and Félix A. Pouchet, which suggests that Pasteur's victory was largely due to religious and political factors which favoured him rather than to experimental evidence. Although this view has been challenged by Nils Roll-Hansen, (...) no historian has yet appreciated the full context of the debate which involves the French Academy of Sciences. The Academy had fostered research through prize-questions on spontanteous generation and related issues for nearly twenty years. This new evidence radically alters the feasibility of Pouchet's support for spontaneous generation.A closer examination of Pouchet's writings shows that his religious beliefs influenced his work at least as much as in the case of Pasteur. Pouchet's deeply held commitment to spontaneous generation was not open to modification in the light of new experimental evidence. It was therefore a clear case of a research programme which was not ‘progressive’ and did not deserve to succeed. (shrink)