Law’s Positivity in the Natural Law Jurisprudence of Thomas Aquinas
This chapter draws upon Thomas Aquinas's analysis of divine law in order to illuminate his understanding of law's positivity, but here it is worth briefly reviewing the theological dimension of Aquinas's analysis of positive law, since it is so often denied by his modern commentators. In Aquinas's first major work, The Commentary on the Propositions of Peter Lombard, he discusses the authority of precepts of divine law and of church law that lack intrinsic moral force. The linguistic context of the emergence of the contrast of natural and positive is important because when positives is deployed in jurisprudence, it retains its close association with the Democritean theory of names as being both adventitious and arbitrary. Natural law justifies the duty to obey positive law as imposed, even apart from the issues presented by the content of that law; and natural law justifies the right to disobey positive law by establishing limits to what is permissible in that content.