Histories of ethics often skim swiftly over the sixteenth century. In the high Middle Ages moral philosophy was presented in commentaries on Aristotle's Nicomachean Ethics and in treatises on the natural or revealed law of God. In Aquinas' Summa Theologiae both elements are combined, but the system is structured around the concept of virtue rather than around the concept of law. It was Aquinas' successors, from Duns Scotus onward, who gave the theory of divine law the central place in presentations of Christian morality.1 But the medieval tradition in ethics suffered a shock, from which it never recovered, under the impact of the Reformation and the Counter-Reformation.
Both Luther and Calvin emphasized the depravity of human nature in the absence of the divine grace that was offered only through Christianity. For them, the path to human salvation and happiness lay through faith, not through moral endeavour, and there was little scope for any philosophical system of ethics. Aristotle was the enemy, not the friend, of the only possible good life. As for other ancient sages, their teaching could not lead to virtue; as Augustine had insisted, the best it could do was to add a certain splendour to vice.
Catholics did not agree that human possibilities for goodness had been totally extinguished by the Fall, and the Council of Trent declared it a heresy to say that all deeds of non-Christians were sinful. But the disciplinary regulations of that council gave Catholic moral theology a new direction which took it far away from Aquinas' synthesis of Aristotelian and Augustinian ethics. A decree of 1551, strengthening a rule of the
1 See vol. II, pp. 263–77.