Friend of certain encyclopedists Denis Diderot and Jean-Jacques Rousseau, it was allured by the ideas of John Locke and Newton, and undertook a descriptive analysis of the understanding, based on only one principle allowing a rigorous “recombining” of the unit (the myth of the “statue”).

Thus, in its Treaty of the feelings (1754), he wanted to show that all our ideas come from the feelings: the touch, paramount direction, the language, sign essential “science is a language well done”, the pivots of a logic and an inciting psychology constitute, constantly called upon and criticized thereafter “Test on the origin of human knowledge”, 1746. French Academy, 1768.