Descartes-Roberval: A tumultuous relationship (Q2714849)

G. Roberval (1602-1675), who from 1634 was on the Ramus chair in \textit{Collège royal} (Paris), had met R. Descartes (1596-1650) only occasionally when Descartes visited Paris from Holland in 1647 and 1648. The author gives same citations from \textit{A. Baillet} [La Vie de Monsieur Descartes (Paris, 1691); re-edit. Hildesheim (1972)], which show that already then there were misunderstandings between Roberval and Descartes about the problem: is a movement possible in the void. The only letter sent by Roberval to Descartes in 1643 has got lost now. The author expresses his surprise that Roberval has the first place (with 142 references) among the other persons mentioned in the correspondence of Descartes, according to the edition by Adam-Tannery. He analyses these references and finds them seeming very contradictive. His explanations are 1) of personal character (that both had privileged relationships with Mersenne), 2) concerning philosophy (that Roberval was clearly anti-cartesian), and 3) concerning mathematics (that the tracks set by Descartes for indivisibles were not accepted by Roberval, as later by Newton and Leibniz). There is a reference to \textit{L. Auger} [Roberval, un savant méconnu (Paris, 1962)].