Are there moral norms for action applicable in all times and places? It was common in the early modern period to answer ‘Yes’ to this question and to appeal to natural law as expressing those norms.
Natural law developed in the early modern period through the work of Suarez, Grotius, Hobbes, Cumberland and Pufendorf, among others. Natural law is a universal, obligatory set of rules for action, known without revelation and legislated by God. The phrase ‘natural law’ carries with it a set of claims about moral norms – where they originate, what justifies them, how we know them.
Early modern natural law has roots in the ancients (particularly in Stoicism) and Christianity. It is a standard part of medieval and early modern Aristotelian moral philosophy, where it informs discussions of law, moral action, and the Ten Commandments. In the seventeenth and eighteenth centuries, however, one sees something novel: philosophers claiming that moral philosophy is fundamentally legal or jural or, even more pronounced, nothing other than natural law. On a jural view of morality, moral principles are imposed – in some sense or other – through legislation. It has often been claimed that this marks a break between modern and pre-modern moral philosophies – from views oriented by happiness, good and virtue to views focused on obligation, law, right, duty and authority.
The most important differences between a scholastic or eudaimonistic conception and a natural law or jural conception of moral philosophy arise in claims about the summum bonum (highest good), the emphasis on law, action and justice, and the nature of moral reasons. Perhaps, most generally, natural law can be thought of as reorganizing morality towards the goal of adjudicating conflict, particularly among religious confessions, warring states, traders and alien cultures.
Natural law informed much academic moral philosophy in the eighteenth century and exerted strong influence on moral and political thought (for example, the American Declaration of Independence). By the nineteenth century, however, utilitarian and historicist critics attacked the ideas of morality as law and of timeless, universal norms as constituting morality. In the present day, natural law ideas are manifest in the human rights tradition.
