1079 – 1142
Peter Abelard (1079–1142) was a French philosopher, theologian, and logician whose dialectical method and razor-sharp engagement with the problem of universals made him one of the most influential and controversial thinkers of the twelfth century. He developed a position on universals often called conceptualism, rejecting both extreme realism and pure nominalism in favor of the view that universals are mental concepts derived from common features of individuals. His personal life, particularly his relationship with Héloïse, and his conflicts with Bernard of Clairvaux shaped his legacy as much as his philosophical writings.
Developed a conceptualist solution to the problem of universals, holding that universal terms signify mental concepts rather than real entities or mere words
Pioneered the dialectical method in theology with Sic et Non, juxtaposing contradictory patristic authorities to spur reasoned reconciliation
Advanced intentionalist ethics, arguing that moral worth derives from the agent's intention, not the act itself
Made significant contributions to the philosophy of language, including analysis of predication, reference, and the semantics of general terms
Established influential schools of logic and theology in Paris, helping lay the institutional groundwork for the medieval university