The Thomistic Distinction Between Primary and Secondary Natural Law Precepts, as Found in the Commentary on the Sentences, the Summa Contra Gentiles, and the Commentary on the Nichomachean Ethics of Aristotle

Abstract

In Chapter II, we established the thesis that for S. Thomas, certain moral precepts are present in the minds of all men. Following the terminology employed in that chapter, we know that these very general precepts of the natural law are self-evident. It is this concept of self-evidence which is going to play a major role as we proceed with our analysis of S. Thomas’s thought concerning the distinction between primary and secondary precepts. It will be remembered that S. Thomas uses this term “self-evident” in a strictly technical sense.1 What he means is not that the precepts in question are innate (in the sense that they are given to man at birth), and thus must be known to everyone; rather, he means that the truth of these precepts becomes apparent, immediately we examine the terms involved. For instance, immediately we reflect on the concept of “goodness” we see without fail that whatever the content of “good” is (and this is something we come to know, after varying degrees of reflection), it is something that ought to be done. And likewise, whatever we discover to be evil—this we immediately know, ought to be avoided. S. Thomas, it will be remembered, draws a parallel between the primary principles of the speculative reason, and those of the practical reason.2 The former are known by the activity of reason called the intellectus, 3 while the latter are known by means of a special habit called synderesis. 4 Thus we concluded our investigation in Chapter II by asserting the existence of a group of moral precepts, which were (in the special sense of the term) self-evident, and consequently, able to be grasped by all men.