 Despite the contributions of Anselm in the eleventh century on questions concerning free choice, divine foreknowledge and predestination, and Peter Abelard’s startling assertion in the twelfth century that morality arises from the agent’s intention alone, it is not until the thirteenth century that a thoroughly scientific approach to human moral reasoning takes shape. Aristotle’s Nicomachean Ethics, newly translated into Latin, provides a philosophical basis on which a fresh examination of Augustine’s doctrines could be based (Wieland, 1981). The first great medieval commentary on Aristotle’s ethics, which was the result of Albert the Great’s teaching activity at the Dominican House of Studies in Cologne, marks the beginning of ‘moral science’ in the Middle Ages. Albert’s careful exposition of Aristotle’s text and his clarification of the concepts of natural law, moral reasoning and human virtue, and its influence on his most famous pupil, Thomas Aquinas, led directly to a consideration of the question of practical reasoning in the Middle Ages.