This launch volume in the Founders of Modern Political and Social Thought series presents a critical examination of Aquinas's thought, combining an accessible, historically-informed account of his work with an assessment of his central ideas and arguments. John Finnis presents a richly-documented critical review of Aquinas's thought on morality, politics, law, and method in social science. Unique in his coverage of both primary and secondary texts and his vigorous argumentation on many themes, the author focuses on the philosophy in Aquinas's texts, and demonstrates how this interconnects with the theological elements. Finnis shows how Aquinas, despite some medieval limitations, makes clear and profound contributions to present debates.