title: [The concept of intensity in Charles Bonnet's psychology].
abstract: The concepts of intensity and vivacity are studied in the psychological texts of Charles Bonnet (1720-1793). In 1854, intensity measured physical movements of the nerves, and vivacity pertained to psychical order. In 1760, however, the two scales were confused. This development, based on an imaginary of measure justified by methodological considerations, led to a research field whose apparent goal was to measure the soul's faculties. Moreover, intensity--which had been quantified in Bouguer's work at that time (1760)--was abandoned and was transferred to the notion of energy, not yet quantified. Consequently, Bonnet's apparent dualism seems, in fact, to have been grounded on a monistic foundation, assuring an unmeasurable place to the soul, corresponding to freedom.
authors.affiliation: Histoire et philosophie des sciences, Université de Genève.
authors.forename: M J
authors.initials: MJ
authors.lastname: Ratcliff
mesh_terms: D001703:Biophysics / Q000266:history; D049671:History, 18th Century; D008722:Methods; D011584:Psychology; D013557:Switzerland; D014894:Weights and Measures
vernacular_title: Le concept d'intensité dans la psychologie de Charles Bonnet.