The History, Enemies, and Importance of Natural Law

Philosophy, says Dr. John Lawrence Hill, “played a fundamental role in my conversion to Christianity. I think most non-Christians—at least if they are thoughtful about these matters—really haven’t confronted themselves with the contradictions of their own worldview.”

Dr. John Lawrence Hill is a law professor at Indiana University, Robert H. McKinney School of Law in Indianapolis, where he teaches constitutional law, torts, civil procedure and legal philosophy courses. He is the author of several books, including The Political Centrist (Vanderbilt, 2009) and, most recently, After the Natural Law: How the Classical Worldview Supports Our Modern Moral and Political Views (Ignatius Press, 2016). Hill holds a Ph.D. in philosophy and a law degree both from Georgetown University. Formerly an atheist, Hill came into communion with the Catholic Church in 2009. He recently responded to questions from Catholic World Report about what natural law is and is not, common objections to natural law, how natural law developed and how it has been undermined, loss of faith in God in the West and the decline of natural law, and his journey from atheism into the Catholic Church.

CWR: What, in a nutshell, is “natural law” and how has it developed from the classical era to today?

Dr. Hill: Natural law is the idea that the world is ordered in a certain way, morally and physically, and that we can draw practical conclusions about how to live based upon what we learn about this order. Natural law means that there are objective moral truths built right into the fabric of the natural world. It means that things work in a particular way because they have been designed with a specific purpose. It means that there are better and worse ways for human beings, individually and collectively, to live.

The greatest of all natural law thinkers, Thomas Aquinas, argued that the natural law is not only “out there” in the world—a set of binding norms that govern us—but is “in here.” We human beings have the natural law built right into us. We have within us, in an inchoate way, a moral template for the development of our conscience—Aquinas called this “synderesis”—which, under proper social conditions, unfolds our moral sense of right and wrong. And even our natural desires are “ordered to the good.” Aquinas’s natural law theory holds that, when human beings are properly educated, we naturally develop into fully-functioning human beings. So, natural law implies that, by following this order, we achieve fulfillment and happiness.

The natural law tradition developed over the course of some two thousand years. It began with the insights of pre-Christian thinkers including Plato, Aristotle and the Stoics. But it was fashioned into a workable system by Christian thinkers, especially Thomas Aquinas in the thirteenth century.

In some ways, our moral and political system is still based on the natural law but we have, since about the eighteenth century, become, as a civilization, intellectually estranged from the natural law tradition. Some of the reasons for this are discussed below.

CWR: What are some of the common objections to natural law today?

Dr. Hill: There are at least two objections that have been continually restated throughout history by those skeptical of the natural law. They are, in a sense, contrary objections. The first misunderstands the idea of “law” while the second misconstrues what we mean by “natural.”

The first objection is that natural law cannot be true because, when we look around the world at the moral outlook of different cultures now and throughout history, we find a dizzying variety of practices and opinions on such things as abortion, infanticide, homosexuality, etc. This lack of moral uniformity indicates, according to skeptics, that there cannot be a natural law “written on the hearts” of men. If there were, and if it were obvious, there would be much more uniformity of judgment in moral matters.

What this objection fails to account for is that human beings were made free—free even to depart from the natural law. And it fails to understand that we can, individually and collectively, “lose sight” of the law.

At the heart of this objection is the misconception that what the law requires will be so patently evident that all moral disagreements will disappear. But there are several problems with this. First, as Aristotle noted, ethical judgments (and practices) fall into the realm of phronesis, not sophia, i.e., practical, not theoretical wisdom. Even where two people may agree about general principles, there will frequently be disagreement about how to apply these principles on particular matters. Does the commandment, “Thout shall not kill” preclude capital punishment? It depends on whether the principle applies only to innocent persons or to those convicted of a crime. The point is, the closer we come to tangible, practical ethical reality, the more variability we should expect. One reason for this, by the way, is that the concrete conditions “on the ground” may require different applications for the same general principle. A culture with limited material resources may adopt different patterns of property ownership, for example, than a relatively wealthier society.

Finally, as Aquinas was well-aware, cultures and peoples frequently “get off the track.” Individuals can be poorly educated or improperly influenced by others and cultures can deteriorate morally—especially when cultures ignore or are skeptical of the existence of objective moral imperatives, as we see in western culture today.

In sum, the existence of the natural law does not ensure uniformity of judgment or practice.

The second and converse objection is that natural law means that whatever people do as a matter of course must be “natural.” Since people seem to “naturally” engage in activities traditionally condemned by the natural law—e.g. infanticide, homosexuality, drug taking—these activities must be “natural.” So, the objection goes, natural law ought to permit these acts, rather than condemn them.

The problem here is that the skeptic has a very different idea of “nature” and “natural” than that of followers of classical natural law theory. For the former, the “natural” is simply what we do. It is “doing what comes naturally,” as the saying goes. Natural law thinkers, however, hold that the “natural” is neither a purely static nor a purely descriptive idea. The “natural” is what we are at our best and most developed and fulfilled: it is what we do when we have approached achieving our telos. The natural, in sum, is what we ought to do, not what anyone does do. And this “ought” is at one with the kinds of actions that are best for us—that conduce to our happiness, well-being and spiritual development.

We can see from these two objections that the term “natural law” is almost an oxymoron for modern thinkers. It is a contradiction in terms because (to the contemporary mind) “law” is what we have to do while “natural” is what we want to do. One of the most important assumptions of natural law theory is that this dichotomy between duty and desire, social obligation and self-interest—the “is” and the “ought”—has been greatly exaggerated in modern philosophy and culture.

CWR: Since natural law is so closely associated with Christianity, notably with St. Thomas Aquinas among others, why would or should secular thinkers embrace or support it?

Dr. Hill: There have always been non-Christian—even non-theistic—natural law thinkers. Some of the pre-modern philosophers, including Plato and Aristotle, began to grope their way toward the idea of natural law well before the Christian era. The Stoics, non-Christian thinkers who flourished between 200 B.C. and 200 A.D. were the real inventors of natural law. They thought the world was governed by a certain “Providence” and used the term “Logos,” i.e., “logic” or order, to describe this pattern or design for the world. (The term “Logos” later became a description of Christ, through whom all the world is ordered, in the Gospel of John.)

Nothing precludes even agnostics and atheists from holding that there is an order to the world and that certain values, ways of living and systems of governing ourselves work better than others. Thus, one can believe in natural law in a loose sense simply by observing that some things “work” while others don’t.

For example, think about Soviet era communism. Here was a worldview promulgated by intellectuals who thought they could create their own order. Yet this pattern of government was so ill-attuned to human nature that the entire system crumbled within seventy-five years of its creation—a world-historic lesson delivered within a wink of an eye, historically.

With all this said, we must add that most natural law thinkers have been theists precisely because they find it difficult to make sense of an order without an Orderer. But it is at least logically possible that the world works in certain ways and not others, irrespective of whether God exists.

Finally, I should mention that there are a group of thinkers who have, within the last fifty years, developed a system of ideas known as the “new natural law.” These thinkers include John Finnis, Germain Grisez, Joseph Boyle and Robert P. George. The new natural law theory attempts to detach natural law theory from any overarching philosophical or theological system. These thinkers conceive of natural law as a system of practical ethical truths which do not depend on belief in God or other metaphysical beliefs associated with the classical natural law tradition. Finnis’ Natural Law and Natural Rights (1981) is the most developed articulation of the new natural law.

CWR: Why is William of Ockham—a Christian philosopher—so significant in the story of the decline and corruption of the classical worldview in general and natural law in particular?

Dr. Hill: The classical natural law theory of Thomas Aquinas and his followers builds on the idea that each thing in the world has a particular nature or “essence.” Plato taught that all classes of things—trees, stars, human beings—are similar to other things of their kind in virtue of their having a certain “form,” i.e., an archetype which represents the perfection of that kind of thing. Plato’s student, Aristotle, concluded that the form of each thing is a natural part of it. Each thing is made of form and matter. The form of humanness unfolds as a human person develops. It is literally our underlying human nature that is realized through the development of the material (biological) process in reproduction, birth and growth.

In the case of human beings, our essence is what we really are. It also provides powerful clues to how we must live in order to achieve our “end” or purpose or specific form of fulfillment in life. Our form or essence gives us our nature. And it is from this nature that we can derive specific conclusions about how we should live, what the good life is, what our political and social institutions should look like, etc. Without the idea of “form” or “essence,” we can no longer draw specific conclusions about our nature and our “end” in life. The very idea that we are designed with a particular end in mind becomes unworkable.

It was this idea—that things of a certain class or species share a specific nature and an essence—that William of Ockham attacked. He lived within a century of Aquinas but challenged the very central assumption of all natural law theory by insisting that there are no forms, essences or universals. Ockham is considered the father of a doctrine known as “nominalism.” Nominalism, from the Latin word for “name,” holds that trees and stars and human beings have no natural essences.

Rather, he argued, we simply name certain things trees because they resemble each other in certain ways. But there is no core essence or nature that they share. We don’t give certain things—trees—the name “tree” because they share the same essence. Instead, we simply apply a name to certain things that resemble each other in some way. Then philosophers come along, Ockham would say, and mistake this feature of our language for an objective feature of the world. There is no essential nature that trees (or human beings) share.

Ockham sort of took the first important step in this direction but carefully cabined some of the consequences of his own doctrines. Thus, he certainly believed in God and even thought that human beings have a natural end which God has built into us. But other thinkers after him continued to chisel away at the foundation on which natural law is grounded.

All of this may seem a rather obscure academic debate, but the consequences of nominalism are devastating—once we follow them out to their logical extreme (as modern thinkers have done.) It means that there is no built-in human nature. We can decide for ourselves what our “end” is. Indeed, we can deny, as many modern thinkers do, that we have any real “end.”

This, in turn, winds up undermining many of our traditional values including human dignity. Why? Because now there is no such thing as the state of humanness. There are only individual human beings with differing capacities. Thus, we cannot say that every human being—regardless of his stage of life (e.g. a fetus versus a person who has been born) or his mental capacities (a fully rational person versus a person with Alzheimer’s disease)—shares the same essential human dignity in virtue of our shared humanness. Once we have abandoned the idea of human essence or nature, we wind up having to make distinction about whether someone lives or dies, for example, on the basis of their present capacities. The very idea of human rights and human dignity become impossible to explain or defend.

The book describes the cascading consequences of nominalism—but make no mistake about it: the moral and practical consequences of nominalism are enormous.

CWR: Overall, how did Enlightenment philosophers treat natural law? How did their approach affect the formation and ordering of modern political states in the West?

Dr. Hill: As you might expect, western thinkers in the early modern period did not throw out natural law theory, root and branch. Rather, there was a period of two or three centuries during which the words “natural law” continued to be used but in surprisingly new ways. As new wine was put in the old “natural law” skin, its central idea slowly morphed, then decayed—before it was abandoned altogether.

Basically, by the seventeenth century, natural law became associated with two distinct ideas—one moral and one scientific. The “moral” portion of the tradition, associated with thinkers like John Locke, began to think of natural law simply as the moral order God had created and imposed on human beings. Natural law was “out there,” a rule made by God that we are bound to discover and follow. But where Aquinas said that this God-given moral law is “in us”—we know the good through our conscience, for example—Locke was notoriously dismissive of the idea that there is a built-in moral capacity for conscience. Indeed, as an empiricist (and following Ockham), Locke was notoriously ambivalent about essences and substances and other aspects of natural law theory. We are born “tabula rasa,” he said. There is no innate moral knowledge. Natural law became the foundation for Locke’s natural rights which, of course, influenced our own founding fathers. But the old idea that there is a natural order to things in which we participate was largely gone.

The other half of the tradition, represented by thinkers like Hobbes, thought of natural law as the empirical laws of human psychology. There is a basic human nature, Hobbes concluded—and it isn’t very pretty. We are selfish and insecure by nature. What moves us is, mainly, the fear of death and the quest for security. Once we have this secured, then those who have consolidated their power, wealth and position seek their own self-aggrandizement at the sake of the less fortunate (as Rousseau observed.)

In sum, the old moral and physical order of the world, as Aquinas conceived it, was sundered into two halves—one physical, one moral. Once isolated, each half could not stand on its own. Science and morality, the “is” and the “ought” drifted apart and came be seen as two entirely separate spheres of reality. Today, many of our most influential thinkers not only do not believe in an objective morality, they increasingly doubt the reality of the laws of science, at is evident in the post-realist movement in contemporary philosophy of science.

CWR: Without natural law, what is the basis for moral judgment and thought in Western societies? From a logical and historical perspective, where do we go from here? What are the options?

Dr. Hill: Chapter 8 of my book describes the trajectory of modern moral thought after the natural law. Classical natural law theory grounds moral truth in facts about nature. It assumes that nature has been created in a certain way, with specific purposes, and that we can draw moral conclusions from this design of nature.

After philosophy began to grow skeptical of the natural law, philosophers had to find another foundation for objective moral truth (for few thinkers, at least initially, wanted to contemplate the possibility that no objective ground for morality exists.) Two movements emerged, both in the 1780s, precisely at the point when the apparent collapse of natural law placed the very idea of objective moral truth in question. One of these systems is utilitarianism; the other Kantian deontology. Both tried to find a different foundation for morality—one not based on God’s design of the world.

In a nutshell, utilitarianism defines the Good by looking at the consequences of our actions. In its classical form, proposed by Jeremy Bentham, it holds that the best course of action is the one that generates the “greatest happiness for the greatest number.” More recent versions of utilitarianism replace “happiness” with personal preferences: the best action is the one that leaves people free to maximize their own desires and preferences.

In contrast to utilitarianism, Kant’s ethical philosophy is grounded on duties and rights, not on maximized beneficial consequences or outcomes. (In fact, where utilitarians tend to think in terms of good and bad, Katians think in terms of right and wrong.)

Kant insisted that the rightness of an action cannot be gauged by its consequences. Certain actions—murder, for example—simply are wrong irrespective of the (occasionally beneficial) consequences that might follow from a particular act of killing. Kant would have agreed with St. Paul and disagreed with utilitarians that one should not do evil in the hope that good may come. Sometimes, one simply has to do the right action, irrespective of its potential consequences. Dropping the atom bomb on Hiroshima might be justifiable on utilitarian terms, but Kant and St. Paul would agree that the killing of innocents is always forbidden, irrespective of the beneficial consequences (saving the greater number of lives of American and Japanese soldiers who would have been killed had the bomb not been dropped.)

What makes certain actions right or wrong, on Kant’s view, is a bit more obscure. Basically, he argued that the right action is the action that is motivated by the right intention, and that the “right intention” is one that accords with basic duties that we have toward others and toward ourselves. These duties, however, are not grounded in natural rights; they are grounded in human reason.

There have been objections and modifications to both groups of theories over the course of the past two centuries. While each continues to have its defenders, it is safe to say that there has been a general slide toward moral relativism in academic philosophy which has accelerated since mid-twentieth century. Having lost nature and God’s plan as a foundation, the very idea of “objective moral truth” has become increasingly difficult to defend.

CWR: What is the relationship between the increasing loss of faith in God in the West and the decline of natural law?

Dr. Hill: Natural law is based on the idea that the world is an ordered and intelligible place—that there is a correspondence between the way nature is designed and our human needs and purposes. As we said earlier, without God, it is difficult to see how we might expect such an ordered correspondence. If you believe the world is simply a cosmic accident, then things evolved the way they have from random causes. There is no reason to expect that the world is in fact ordered and purposeful in its design. Nor can you believe that there is a “law above the law”—a transcendent moral foundation that creates limits for human-made law. So, it is perfectly “natural—if you’ll forgive the pun—for a world that has lost its faith to become skeptical of the natural law.

CWR: What role did natural law and related philosophical matters play in your conversion from atheism to Christianity?

Dr. Hill: My conversion began when I realized that the many of the things I had been writing about as a philosopher and a law professor required a belief in God. You can’t really believe in human rights unless you believe that there are binding moral foundations that limit the positive law of particular countries. This foundation cannot be predicated on human agreement since agreements may themselves be immoral or unjust. There has to be something outside the bounds of human agreement that grounds and limits our morality.

As I thought about it more, I came to see that all of our most important values require a God-centered foundation. For example, freedom has become our preeminent value in modern political thought. But what is freedom? Freedom is a Janus-faced idea. It points outward to our political liberties (“freedom” in the external sense of having certain rights) but it also points inward, to the idea that human beings make free choices—that there is this mysterious capacity we call “freedom of the will.” Political liberties are external legal protections for the free choices that we make. If we grow skeptical of freedom of the will, political liberty will soon become an obsolete concept.

And, this, I think is exactly what we see happening in intellectual thought today. Secular atheists don’t really believe in “freedom of the will.” They can’t make sense of it because it requires a departure from the normal cause-and-effect way that most materialists view the world. Sophisticated atheists are usually “determinists.” Determinism is the idea that we don’t really make free choices—that no one is really responsible for anything they do because our actions our simply products of our biology and environment. And, corresponding with this, we have seen in the last century a re-definition of “freedom” in the political sense. Increasingly freedom is associated with rights to certain material resources—to a right to health care or a right to have a job at a certain wage. I’m not saying that these aren’t valuable things, but they aren’t freedom.

In short, philosophy played a fundamental role in my conversion to Christianity. I think most non-Christians—at least if they are thoughtful about these matters—really haven’t confronted themselves with the contradictions of their own worldview. They haven’t traced out all of the consequences of their atheism. For, if you’re an atheist, you can’t believe that there are objective moral truths. You can’t believe in human rights. You can’t believe in any real conception of human dignity. And you can’t even believe in that most vaunted of all liberal values—freedom.