Port-Royal Logic originally entitled La logique, ou L’art de penser, a treatise on logic, language, and method composed by Antoine Arnauld and Pierre Nicole (1625–95), possibly with the help of Pascal, all of whom were solitaires associated with the convent at Port-Royal-des-Champs, the spiritual and intellectual center of French Jansenism. Originally written as an instruction manual for the son of the Duc de Luynes, the Logic was soon expanded and published (the first edition appeared in 1662, but it was constantly being modified, augmented, and rewritten by its authors; by 1685 six editions in French had appeared).
The work develops the linguistic theories presented by Arnauld and Claude Lancelot in the Grammaire générale et raisonnée (1660), and reflects the pedagogical principles embodied in the curriculum of the ‘little schools’ run by Port- Royal. Its content is also permeated by the Cartesianism to which Arnauld was devoted. The Logic’s influence grew beyond Jansenist circles, and it soon became in seventeenth-century France a standard manual for rigorous thinking. Eventually, it was adopted as a textbook in French schools. The authors declare their goal to be to make thought more precise for better distinguishing truth from error – philosophical and theological – and to develop sound judgment. They are especially concerned to dispel the errors and confusions of the Scholastics. Logic is ‘the art of directing reason to a knowledge of things for the instruction of ourselves and others.’ This art consists in reflecting on the mind’s four principal operations: conceiving, judging, reasoning, and ordering. Accordingly, the Logic is divided into four sections: on ideas and conception, on judgments, on reasoning, and on method. S.N.