Peter Abelard argued that sin lies not in the act but in the intention behind it, a claim that scandalized 12th-century Paris. His affair with Héloïse, his castration at the hands of her uncle, and his repeated condemnation by the church made him one of the most dramatic figures in the history of philosophy.

This episode traces how Abelard's ideas about ethics, logic, and language transformed medieval thought, and why his love story with Héloïse remains one of the most celebrated in Western literature.

• His revolutionary claim that morality depends on intention, not action
• The affair with Héloïse and its brutal consequences
• His feud with Bernard of Clairvaux
• How his method of dialectical questioning anticipated the university system