There are other features of the natural law approach that distinguish it from competitive normative ethics. First, as has been mentioned, there is the fundamental principle of natural law: to do the good and avoid evil. Try as hard as we might, we cannot find a principle more fundamental than this, and it is known intuitively, not discursively. Call this the Principle of Intelligibility of actions. This means, then, that only actions committed somehow in conformity with this principle are intelligible. Thus, if they are in some way not in conformity with this fundamental principle, then they are not intelligible and hence not candidates for moral approval. Yet, we find that we are unable to simply follow the “good” in abstraction; Aquinas correctly showed that we can only follow and pursue the good taken in particular. Hence, we find the catalogue of basic goods that are to be pursued, which are known immediately and by inclination. Aquinas gives us five: life, procreation, knowledge, society, and rational conduct (which is to act in accord with virtue).[i] This need not be taken as an exhaustive catalogue, yet they are presented as self-evident.
As dictated by the fundamental principle, then, goodness has priority over rightness. That is, rightness is to be understood in terms of goodness; it is logically posterior to whether or not the action realises some good. Hence, from an understanding of the basic goods and the fundamental principle of the natural law we are able to reason to guidelines as to how these and other goods are to be pursued.[ii] Aquinas gives us several clues as to what to look for in determining what counts as a good action, and this is related to the intelligibility principle. A good action, it turns out, is one that is not in some way intrinsically flawed. To understand how this is possible we must look at what individuates an action. These might be characteristics such as the action’s objects, ends, circumstances, or even the agent’s intentions.[iii] Perhaps an action mistakes a means for an end, or an improper end for a proper end. Or perhaps the circumstances were such that the action was improper at that time and place. Or further perhaps the action was flawed through the intent itself, as seeking to murder or commit adultery is always to act contrary to reason and the principle of the good.
It seems rather clear that there will never be an entirely straightforward and fully articulate rule or method for determining just when an action is fundamentally flawed. One could, presumably, endorse a rule-based, Kantian-style, system and deduce rational conduct from it. Such a system, however, will always run afoul of situations that seem to defy classification or of fitting into rigid designations. John McDowell has demonstrated this sufficiently in his ethical writings. A methodological approach would be better, but it is unclear as to what precisely such an approach would look like. There is the strong suspicion that it would look very similar to the inner, not always conscious, workings of the mind of the virtuous person. If such, then, let us advocate, as many others do, an Aristotelian-style virtue approach to understanding the goodness of actions. We know, intrinsically and without a doubt, that there are some rules of the natural law that cannot be broken; these are clear. For those that are less clear, however, we need the person who possesses practical wisdom. The great and foundational Aristotelian insight is that the particulars of the situation will always outstrip our rules and frameworks. We cannot fit life that easily into a mould. Hence, there will always be a need for the moral and intellectual virtues in order to know how to conduct one’s actions in keeping with the intelligibility principle. In this, natural law takes a giant leap from Aristotle.
That being said, it should be clear where the natural law approach stands in relation to other normative ethics. In siding with goodness over the right natural law takes side with the Utilitarians. There is, however, no imperative to maximise the good towards, say, more pleasure and less pain. Further, although considerations of the common and greater good are always taken, contrary to Utilitarianism some things are always wrong. For example, it is always and everywhere wrong to kill the innocent, and no amount of good consequences will suffice to justify such action. In this natural law has something of the Kantian feel, although not entirely. Nor should natural law be taken to be wholly or even overtly Aristotelian. On Aristotle’s account the good is highly particular, and dependent solely on the judgments of the person of practical wisdom. The fundamental precept of natural law, and the basic human goods, are knowable universally, however, and thus wholesale particularism must be rejected.