The starting point for the following reflections comes from Jacques Roger’s monumental work, Les sciences de la vie dans la pensée française du XVIIIe siècle. I hope my remarks may cast some light on a problem that has long remained obscure, and doubtless was to Buffon himself: the status of matter in general and the relation of brute to organic matter in particular.

I. L'organisation -- II. La génération -- III. La sensation.