LOGIQUE: ou réflexions sur les principales opérations de l’esprit.

12mo, pp. xvi, 138; a4 and a5 misbound at end, but present; occasional small marginal tears, and light spotting in places, but largely clean and crisp throughout; in contemporary pink mottled boards, handwritten paper label on spine; binding worn but sound.

Uncommon later edition of this treatise on logic by the French philosopher and encyclopédiste César Chesneau, sieur Dumarsais (1676-1756).

First appearing posthumously in 1769, where it was accompanied by a theory of grammar, the Logique here is presented on its own, as part of a series of classic works 'approuvés par MM. le principal et professeurs du collége Louis-le-grand'. It is one of several books, according to the verso of the half-title, approved for the elementary logic classes at the college (originally the Jesuit College de Clermont, and still extant as the Lycée Louis-le-Grand, on the rue Saint-Jacques in Paris); other authors include Condillac, Bonnet, Clarke, and Fénélon.

Dumarsais's conception of logic is a broad one: 'the principal operations of the spirit'. He discusses the mind/body distinction, the nature of the soul, ideas, reasoning, the syllogism, and sophisms, the explanation of various types of which takes up most of the second half of the book. He concludes with reflections on dilemmas, induction, and philosophical and scientific method.

D'Alembert said of the Logique, 'Ce traité contient, sur l'art de raisonner, tout ce qu'il est utile d'apprendre, et sur la métaphysique, tout ce qu'il est permit de savoir'.

OCLC records copies at the Academy of Architecture at Mendrisio, Hamburg, Oxford, and Brown.