Germain Gabriel Grisez (September 30, 1929 – February 1, 2018) was a French-American philosopher. Grisez's development of ideas from Thomas Aquinas has redirected Catholic thought and changed the way it has engaged with secular moral philosophy. In 'The First Principle of Practical Reason: A Commentary on the Summa Theologiae, I-II, Q. 94, A. 2' (1965) Grisez attacked the neo-scholastic interpretation of Aquinas as holding that moral norms are derived from methodologically antecedent knowledge of human nature. Grisez defended the idea of metaphysical free choice, and proposed a natural law theory of practical reasoning and moral judgement which, although broadly Thomistic, departs from Aquinas on significant points.
Through the prism of his reworking of Thomas Aquinas's take on natural law theory, Grisez also was one of the most outspoken and forceful defenders of traditional views on contested matters in sexual morality, such as birth control and abortion. He also wrote influential articles on biotechnology and how such technologies could be used either to support palliative care and the dignity of life or speed up the end of life.
- The Way of the Lord Jesus Complete text of the three volumes and additional material
- The Making of a Moral Theologian, Russell Shaw. 1996 article on Grisez's personal and professional life, including his work for Cardinal O'Boyle of the Diocese of Washington D.C.
- Biotechnology and Human Dignity in the Thought of Germain Grisez, Nicholas C. Lund-Molfese. Describes the necessity of the Christian virtue of hope in choosing the good of the human person in so-called "hard cases".