Lawrence Dewan, Legal Obligation, and the New Natural Law

IN AN ARTICLE entitled "St. Thomas, Our Natural Lights, and the Moral Order," Fr. Lawrence Dewan, in responding to the "New Natural Law" approach to ethics elaborated by John Finnis, does two things.¹ First, he reminds us that ethical reflections are preceded by sapiential seeds planted in the human intellect through its cognition of being, and so our knowledge of good is preceded (logically) by knowledge of being. Second, he shows that the grasp of being as good entails an incipient awareness of being bound to an order of goodness with God as its ultimate source. In the course of doing the latter, he provides a paragraph dense with footnotes emphasizing the legal character of natural law. It is this legal character of the natural law that I am interested in examining, and contrasting with the approach of the New Natural Law (NNL) theorists.²

I. Determination of the Rule

It will be well to begin with an example of the reasoning St. Thomas Aquinas employs when determining the right rule governing our pursuit of a naturally given end. As is well known, St. Thomas determines that the first rule governing the begetting and rearing of offspring is that sexual intercourse is to be reserved to the married.³ In his disputed questions De malo, we find an objection to that thesis, working from the premise that the end of nature can be preserved even if the means employed is not marital coitus.⁴ Saint Thomas's reply to this argument emphasizes the couple's need to order themselves to the common good, that is, to obey the law in their use of generation. In other words, the couple are not competent to determine for themselves the means by which they order themselves to that good: "it ought to be said that the act of generation is ordered to the good of the species, which is a common good. But a common good is ordainable by law, whereas a private good falls under the ordination of each person." The means prescribed by law must be employed even if it is judged that the end can be attained by other means: "although in some case the intention of nature can be saved in an act of fornication with respect to the generation and education of offspring, nevertheless the act is disordered according to itself and a mortal sin."⁵

The idea that willing subjection to the rule provides an act with moral rightness is congruent with what St. Thomas determines earlier in the work concerning what belongs essentially to the concept of sin:

it is clear that to omit the rule of action belongs more to the notion of sin than even to fall short of the end of the action. For this belongs per se to the notion of sin, whether in nature, or art, or morals, that it is opposed to the rule of action.⁶

For St. Thomas, the voluntary refusal to follow a rule, set by a lawmaker, belongs to the essence of sin or moral failure. Conversely, one acts well when one acts according to the rule.

The rule to be followed in pursuing the end of generation is identified as the limitation of sex to marriage. Saint Thomas arrives at that rule by a resolutive process, moving from the end intended by nature to the means "proportioned" to that end. The means are thus seen to be necessary on account of the end, and the end is seen to belong to us in virtue of a natural inclination. But if the necessity of specific means depends solely on the supposition of a natural end, how does that supposition impose a moral obligation to use those, and only those, specific means? Why is the human will bound to will only those means? In other words, what is it that makes this rule governing a hypothetical order to an end a precept or law that must be obeyed?

II. The New Natural Law Critique

New Natural Law theorists maintain that such reasoning...