 The earliest medieval commentators on the Nicomachean Ethics analyzed only the first three books of the work for reasons yet unexplained (Celano, 2022). The medieval authors of the first half of the 13th century, while aware of the existence of the remaining books of the Nicomachean Ethics generally had only the partial text at their disposal. Aristotle’s discussion of phronesis was mostly unknown until Robert Grosseteste’s complete translation of Aristotle’s text and the accompanying Greek commentaries appeared about 1248. During this period theologians such as Philip the Chancellor and William of Auxerre examined the nature of the moral act in their theological Summas. Like many medieval authors, William of Auxerre considered the Aristotelian virtue of phronesis (prudentia) to have both an intellectual component as a type of knowledge as well as a moral function in its ability to prescribe proper actions. Both William of Auxerre and Philip the Chancellor were instrumental in introducing into moral theory the concept of synderesis which they viewed as an innate human ability to recognize the eternal first principles of moral reasoning. Rather than leave the guiding principles of human actions to human experience they anchored moral decisions in the eternal law of God. Synderesis displays a universal code of correct actions to the moral agent (Eardley, 2021). Although their interpretation was decidedly un-Aristotelian it did influence the conclusions of later commentators, such as Albert the Great and Thomas Aquinas. After the appearance of Grosseteste’s translation Albert the Great composed the first Latin medieval commentary on the entire text of the Nicomachean Ethics. His treatment of the prudence as a virtue with both intellectual and moral components, his acceptance of universal moral principles in the natural law, and his understanding of practical reason and its relation to human happiness had a profound effect upon the writings of his student, Thomas Aquinas.