Aquinas on Conscience and the Inner Act of the Will - Fr. David Goodill, O.P.
The Thomistic InstituteShow Notes
Fr. David Goodill expounds Aquinas's treatment of conscience in Summa theologiae I-II, q.19, arguing that conscience is the inner act of the will and that, even when erring, it binds the agent, such that right formation of conscience through virtue, law, and grace is essential.
This lecture was given on July 24th, 2026, at Stonyhurst College.
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About the Speaker:
Fr. David is Dean of Degrees, Lector, Fellow, and Provincial Bursar. He studied Philosophy in Cambridge and Manchester before entering the Dominican Order. He has a doctorate in Moral Theology from the University of Fribourg, Switzerland, and maintains interests in both Moral Philosophy and Moral Theology. He was Prior of Oxford, and has served Blackfriars Hall and Studium as Hall Bursar, Vice-Regent, Senior Tutor and Acting Regent. He is a visiting lecturer in moral theology at St Joseph’s University, Macau.
Publications: ‘Original Sense: Augustine and Wittgenstein on Religion and Origins’ in Augustine and Wittgenstein (2018); ‘Elizabeth Anscombe on Just War’ in The Moral Philosophy of Elizabeth Anscombe (2016); Nature as Guide: Wittgenstein and the Renewal of Moral Theology (CUA Press, 2022).
Keywords: Aquinas, Conscience, Erring Conscience, Grace, Intention, Moral Species, Object Of The Act, Prudence, Summa Theologiae, Virtue
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