Abstract

Due to the historical origin and development of reason, an inventory of its main concepts at a particular moment is less interesting to us than the study of their formation and fixation. This process is studied here in the light of examples from the history of physics. The first one concerns the subsumption of the well-known phenomena of free fall and planetary motion to a new concept of gravity in the 17th century; the remaining examples, drawn from 19th century electrodynamics and 20th century microphysics and cosmology, display the interplay of such concepts with empirical novelties that prompt them in some case and realize them in others.