Natural law

Natural law theory holds that there are moral standards grounded in human nature and knowable by reason, which human laws should follow.

Its roots lie in Aristotle, the Stoics and Cicero, and Thomas Aquinas gave it its classic Christian form in the thirteenth century. In the sixteenth and seventeenth centuries Francisco de Vitoria and Hugo Grotius applied it to the rights of peoples and the law of war, helping to found international law, and in the twentieth century Lon Fuller argued for an inner morality of law. It is distinct from the laws of nature studied in science. On this site it answers questions on war and political violence (3.3.5), divine command, duty, law and moral language.