D’Alembert or on the Good Physics

Abstract

We analyze, through writings of d’Alembert, the complex relationships that mathematics, physics and metaphysics entertain with man’s faculties and their linguistic manifestations and highlight critical issues and philosophical and epistemological consistency, which we consider valid and actual. For the illuminist d’ Alembert all good physical science is established and developed on a good philosophy and vice versa, as any good philosophy must be con solidated on a good metaphysics, to fertilize then good science. A well-structured science can then only be founded on a well-constructed language. Then the good metaphysics is above all critical of abusive and badly constructed languages, confused, quirky, nominalistic, empty, contradictory, when they hypostatize or reify mere names (force, cause, infinitesimal , infinite, axiom), they transform mere relations between simple physical properties in physical entities (velocity, acceleration, differential) or exchange names for questions about physical realities (the querelle about living forces), generic and vague names (being, substance, idea) for metaphysical principles (Plato, Aristotle, Scholastic).