Which French writer translated Newton's 'Principia' into French?

Émilie du Châtelet translated Newton’s Principia into French. Her translation, accompanied by extensive commentary and mathematical work, helped make Newtonian physics accessible to French-speaking readers.

Du Châtelet worked on the translation during the 1740s and consulted leading mathematicians, including Alexis Clairaut. Newton’s Principia had originally been published in Latin in 1687, so translating it required much more than replacing words between languages. Du Châtelet checked calculations, clarified difficult arguments, and added material explaining the planetary system and related scientific questions.

The work was published after her death: an initial edition appeared in 1756, followed by the definitive two-volume edition in 1759. Clairaut helped supervise and edit the project, while Voltaire wrote a preface. A common mix-up is to describe du Châtelet merely as Voltaire’s companion; she was also a serious mathematician and physicist whose translation remained an important French version of Newton’s work.