Estimated reading time: 8.5 minutes (1665 words)

The term “natural law,” normally confined to philosophy classrooms and Catholic schools, has broken out into wider public conversation. This is true, in part, because of debates around gender and sexuality, but also because some have associated natural law with the ideological position of some of our Supreme Court justices.

These developments mean that the term carries with it a suspicious aura, as though it were merely a name for old-fashioned and oppressive norms, as though natural law consisted in nothing more than backwards people saying “well heck, it ain’t natural!” about things they don’t like.

Anthony Murray, a lawyer who has written critically of natural law in The Atlantic, characterizes  this theory in terms that are so confused and uninformed that they are wonderfully instructive about the mistakes made by society more broadly in this regard. Although the article was written some 10 years ago, it was written in reference to justices still on the court, and in terms still prevalent today, such that it remains instructive.

Murray conflates natural law with “divine morality,” and frets that the term is really a cover for a person’s subjective beliefs, but also a cover for religious dogma that allows no room for dispute. In this inconsistent description, there are a number of competing errors. 

First, is that “natural law,” as traditionally understood by thinkers like Thomas Aquinas, is not at all identical with “divine morality.” To begin, Aquinas, and those within the tradition of which he is a part, would find the idea of “divine morality” redundant and confusing. Since God, for them, is nothing other than goodness itself, there is no morality apart from the divine. But what really concerns Murray, and many Americans, is the idea that somebody could impose their religious beliefs on him. Divine morality, for him, stands for religious commands. Murray is correct that, in this country, it is not appropriate for someone to impose the moral commands of his particular faith on those who do not share that faith. But this is precisely on area where natural law theorists distinguish natural from divine law.

Since it is the views of Catholic jurists that worry Murray, we will take Aquinas as a paradigmatic expression of the natural law tradition. For Thomas, divine law refers to those commands proclaimed in revelation, that is, in the Bible. Some of these line up with natural law, but others go beyond it. The commands not to murder or not to steal, for instance, overlap with natural law, while commands about divorce and remarriage might be an example of divine law. The difference is that divine law can only be known from scripture, while natural law can potentially be known by any person just by looking at reality and reasoning about it. Natural law, then, names specifically those moral precepts that do not belong to any specific sect or revelation.

Natural law refers to those moral truths discoverable by human reason through the observation of human nature. Scary, right? Of course, you and I and everyone else use natural law reasoning all the time. Suppose you’re a parent, and you want your kid to spend less time on her phone and to be outside more. Why? Because it is good for kids to play outdoors!! Now that is an interesting statement. When setting a rule that our daughter has to limit phone time and expand outside time, we reason from a universal claim about nature: it is good for kids to be outside. This doesn’t mean that we are being unqualified or dogmatic; we recognize that it is not good for a sick or impoverished child to be outside all the time, but, all else being favorable, it is good for kids to be outside in nature. Our decision is not based on the child’s subjective preference or our own, but a conviction that this is something simply good for our kid, whether they like it right now or not.

We can push the reasoning a little further. Why is it good for kids to be outside? Because fresh air is good for their lungs, exercise is good for their hearts, and beauty is good for their minds. It turns out that we know even more about human nature than we thought. We know that there are certain capacities characteristic of the human way of being, and that among these are the ability to breathe, to move, and to enjoy what is beautiful. We recognize these capacities as good and as contributing to a good life characteristic of the human way of being. We want our child to be a good and happy human, and we know what that is based on our understanding of human nature. Wow, spooky stuff! Or perhaps natural law is actually something like moral common sense.

And indeed, it is very common! Murray is worried about Christians, because he doesn’t like what Christians believe, but one need not at all be a Christian to think in a natural law kind of way. Pagans like Aristotle, great Muslim thinkers like Ibn Rushd, the great Chinese thinkers like Meng Ke and Cheng Hao, all found an important role for natural law. Contemporary philosophers like Phillipa Foote and Elizabeth Anscombe revived the idea in their own way. C.S. Lewis famously called natural law simply the “Tao,” because it was a kind of moral reasoning that universally could be seen across time and space. 

I hope that from the foregoing you see that natural law is not the scary boogeyman Murray thinks it is. What’s more, natural law is perhaps essential for any healthy civic life in a religiously diverse society. It is attractive precisely because it holds that there can be moral agreement among people with differing religious beliefs. Not on everything, but on many important things. To embrace natural law theory is to embrace the idea that public discussion is possible between people of different parties, backgrounds, and sects based on the observation of human nature, and that it is not necessarily reducible to mere exertions of power.

Furthermore, as the scholar Hu Shih points out, it is the means of challenging established power structures. Natural law says that there is an authority higher than the people who happen to be in power, an authority to which they are held accountable, namely, the natural moral law. There is a long tradition of Chinese dissenters speaking truth to power by way of showing the dissonance between the actions of the powerful and the dictates of natural law. It was the same style of reasoning that Martin Luther King Jr. used when he made his impassioned natural law argument for civil rights in the “Letter From a Birmingham Jail.”

But there are a few more concerns that might arise. If natural law were really so universal, why is there so much disagreement on morality? The fact that natural law is based on things we can all observe does not at all mean that deducing the right conclusions is easy and obvious, any more than the fact that physics is based on what we observe makes its conclusions easy and obvious. Morality is far more contextual than physics, and it is so embedded in personal life that it is more difficult still. Natural law does not say the answers are easy, it only says that there is a common ground on which we can reason together about right and wrong, advancing arguments rather than just exerting power and asserting opinion.

But doesn’t nature contain all kinds of horrible things? If we lived according to the law of nature, wouldn’t that just be the law of the jungle? This is an understandable confusion, but natural law does not refer to whatever happens to obtain in “nature” meaning “amongst animals,” nor does it refer to what occurs in human beings in a “state of nature,” whatever that means. Observing chimps or gorillas or ants or whatever is no kind of natural law reasoning. Nor is natural law reasoning an endorsement of whatever happens to have been the pattern of human history, or of current human society. Rather, it is an investigation into the nature of the human person as such, of her capacities, possibilities, and happy fulfillment as the human being she is.

Doesn’t natural law mean that everyone must act exactly the same way? Doesn’t it flatten everyone out to some kind of narrow idea of human flourishing? It certainly doesn’t have to. Natural law is not a set of moral commands that tells you what to do in every circumstance, it is a background by which free and rational persons can use their judgment and prudence to decide what to do in particular circumstances and relationships. Natural law does not say that everyone will flourish only by having any one kind of personality, pursuing any one kind of work, or enjoying any one set of activities, but it does say that nobody will flourish by breaking natural law, that is, by doing things like stealing, lying, cheating, murdering, and so on. It also says that there are certain things that will be part of any flourishing life, like the use of our reason, of our freedom, of our creativity, of our sense for beauty, of our capacity for love, which are all aspects of our nature as human persons. 

This is far too short a space to go into all the many academic back alleys that can be explored in moral theory. I hope, however, to have given you a better picture of what natural law is really about, instead of the silly characterization of a writer like Anthony Murray. Natural law is much more interesting and indeed intuitive and attractive than it is made out to be. What’s more, I think you already are a natural law theorist, because it’s just natural to reason about right and wrong in this way. As hard as you might try, I don’t think you’re going to stop believing that there are things that are right and wrong by nature anytime soon.

Nathan Beacom is a writer living in Des Moines, Iowa. He is the founder and director of the Lyceum Movement.