The Thomistic Distinction Between Primary and Secondary Natural Law Precepts, as Found in the Summa Theologica

Abstract

In Chapter III, we Concentrated our attention on the doctrine of primary and secondary natural law precepts, as it occurred in S. Thomas’s early writings—the Commentary on the Sentences, the Summa Contra Gentiles and the Commentary on the Ethics. This brings us now to the Summa Theologica, our author’s last and major work. Here, as might be expected, we find some of S. Thomas’s most mature reflections concerning the division of precepts, and we note that, in contrast to the teaching in the Commentary on the Sentences, the approach is exclusively philosophical. In Question 94 of the Prima Secundae, such questions are raised as: whether the natural law contains several precepts or only one; whether all acts of virtue are prescribed by natural law; whether the natural law is the same for all men; whether the natural law can be changed? These questions reflect the systematic and exhaustive nature of S. Thomas’s approach.