Mainly remembered as the mistress of Voltaire, Emilie Du Châtelet (1706–1749) was a writer in her own right, who published multiple editions of her scientific writings during her lifetime, as well as a translation of Newton’s Principia Mathematica that is still the standard edition of that work in French. For this edition, Zinsser has selected key sections from Du Châtelet’s published and unpublished works, as well as related correspondence, part of her critique of the Old and New Testaments, and a treatise on happiness.