This book traces the history of rationalist organizations in France since the 1930s. In particular, it focuses on the events surrounding the creation of the Rationalist Union in 1930 and the French Association for Scientific Information in 1968.

Even if the rationalist organizations described in this book rarely seem to exceed a handful of a few thousand members, they constitute a sociological object that enables us to ask questions that are conversely broader than their size or relative confidentiality might suggest. They show under what conditions and by what processes "reason" or the "defense of science" can be permanently erected as a political argument and mobilized in the public arena by science enthusiasts or by scientists themselves.

A conditional extension of the scholarly ethos, these fragile commitments are intimately bound up with both the state of bureaucratic research structures and the objectified forms of scientific truth production. In France, rationalist investment was, in many respects, born out of the very specific historical context of the 1930s, a context in which certain scientists had to both gain administrative autonomy from political and military powers and counter the structuring of an intellectual world based on religion.

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