French philosophy, here taken to mean philosophy in the French language, has been extremely diverse and has influenced Western philosophy as a whole for centuries, from the medieval scholasticism of Peter Abelard, through the founding of modern philosophy by René Descartes, to 20th century philosophy of science, existentialism, phenomenology, structuralism, and postmodernism.
Peter Abelard (1079 – April 21, 1142) was a scholastic philosopher, theologian and logician. The story of his affair with and love for Héloïse has become legendary. The Chambers Biographical Dictionary describes him as "the keenest thinker and boldest theologian of the 12th Century".
The general importance of Abelard lies in his having fixed more decisively than anyone before him the scholastic manner of philosophizing, with the object of giving a formally rational expression to received ecclesiastical doctrine. However his own particular interpretations may have been condemned, they were conceived in essentially the same spirit as the general scheme of thought afterwards elaborated in the 13th century with approval from the heads of the Church.
He helped to establish the ascendancy of the philosophical authority of Aristotle which became firmly established in the half-century after his death. It was at this time that the completed Organon, and gradually all the other works of the Greek thinker, first came to be available in the schools. Before his time Plato's authority was the basis for the prevailing Realism. As regards his so-called Conceptualism and his attitude to the question of Universals, see Scholasticism.