What is Natural Law?

Janet E. Smith
Reproduced with Permission

I. What is Natural Law?[1]

Catholic ethics can be approached both from a philosophical perspective or a theological perspective. The truths of philosophy are those discovered by man as he observes and thinks about reality; truths, discovered in this way are said to be the truths of reason. Those truths that are discovered and established by reason in the moral realm are called the truths of natural law. Most philosophers grant that we do not need revelation to figure out that some acts, such as murder, adultery, rape, and theft are wrong.

Theological ethics have as their chief sources revelation and tradition. Often revelation reveals to us what we can know through reason (see the 10 commandments) but also reveals to us truths that are beyond our ability to discover without the help of revelation. The Christian teaching, that we must love our enemies, for instance, seems to go beyond reason.

The Catholic Church teaches that human beings are capable of figuring out what is moral and immoral in the realm of sexuality without special revelation. Thus, Catholic sexual ethics are based on natural law. One of the great proponents of natural law ethics is St. Thomas Aquinas who was greatly influenced in his thinking about philosophical issues by Aristotle. Neither revelation nor theology, of course, are irrelevant either to natural law or sexual ethics, but the Church holds that the fundamentals of both are knowable without recourse to revelation - and such is what makes it possible for men everywhere to come to some agreement about morality.

A feature that distinguishes Aristotelian and Thomistic Ethics is what is called realism (the philosophic position identified as essential to Catholicism in Fides et Ratio ). This means that there is an external world that we are capable of knowing through our senses. To most "ordinary" human beings, such a claim seems uncontroversial since it seems obvious that there are such things as dogs and milkshakes and songs and that I can get to know through my senses. But much of modern philosophy (especially since Descartes) has been based upon the premise that we cannot trust our senses and some even argue that we cannot even know that there is a world outside of our minds (possibly Kant's position).

Aristotle and Aquinas believed that human beings are made in such a way that we can discover truths about reality starting with the information given to us by our senses. This is an important truth for ethics, since the Catholic Church claims that morality is an area of knowledge that human beings can know a great deal about without the aid of revelation. In his great work the Summa Contra Gentiles , Aquinas labored to show the ancients, such as followers of Aristotle, that the truths of revelation were compatible with truths they had discovered through their thinking about what they had observed about reality - he was trying to get them to be more open to revelation. One truth that our reason discovers is that things have essences or natures and purposes and that it is good to act in accord with those essences or natures and purposes. This is a truth of fundamental importance for ethics, for once we know the purpose of human life and sexuality we will better be able to live morally.

It cannot be stressed too strongly that natural law ethics do not proceed by positing the essence of man and then deducing or deriving moral norms from that essence. Nor can it be stressed too strongly that natural law does not proceed by looking at the world of nature and saying - "since X is the case, Y is moral or immoral." That is, it does not derive moral norms simply from observing that such and such is the case in the world as we know it. Natural law is an ethics that requires much observation of the world around us and also penetrating insight into the nature of things. Such insight, in fact, is the gained through a process of induction based upon what we know about the world around us. It is a process of observation and deduction that leads us to recognize that man is a rational animal; it is through much experience of man that we learn what his natural inclinations are and to what goods he is naturally inclined. Once we discover what his nature is, what his inclinations are, what the goods are to which he is naturally inclined, then we must discover and also determine what are good means of achieving those goods. For instance, natural law sexual ethics begins with the observation that man has a natural inclination to sexual intercourse, and natural inclinations to loving unions and to having children and that all of these activities are interrelated. The more we know about the nature of sexuality, of the desire/need of human beings for loving unions, of the desire/need of human beings for have children and to the needs of children, the better we will be able to determine what kinds of actions help us achieve the goods that we seek - actions that must not only be successful but which also perfect our characters. That is, whatever means we select to achieve our goals must be means that nurture our growth in virtue.

Virtue based ethics and natural law are intertwined. Virtue based ethics assert that all human beings because of the nature of their souls need certain dispositions in order to achieve the goods that they need. The four cardinal virtues are moderation, courage, justice and prudence. Acts such as drunkenness that violate moderation are against virtue and therefore the natural law and acts such as sobriety that nurture moderation are therefore in accord with the natural law.

The fact that natural law is based upon reason, upon thinking about one's observations about reality, makes the ethics of natural law a universal ethics since all human beings by their nature are able to reason, are able to think and thus to arrive at some universal truths. Everyone acknowledges that the truths of mathematics, geometry and physics are universal but many claim that the truths of morality are not. Still, most everyone now realizes that slavery is wrong and that any culture that allows slavery is a culture that fails to recognize a universal truth about human beings and that is that they should never be owned or treated as property.

Natural law morality, in a sense, is simply plain old common sense. There are profound and sophisticated ways of explaining natural law, but the practice of reasoning in accord with natural law principals, according to the theory itself, is natural to ordinary people - that is, natural to all mankind for natural law holds that many of the most fundamental precepts of moral reasoning are obvious, that is easily known by all. Yet, in spite of the plain commonsensicalness of natural law, it can seem shocking and provocative in many ways, for like natural law, plain old common sense does not command a lot of followers these days and can be shocking when juxtaposed to the values of our times.

Here it is not possible to give a full presentation of what natural law is but let me at least provide a list of some of the philosophic claims fundamental to natural law (these are not necessarily easily known by all):

Although the following discussion will provide no systematic explanation or defense of these principles, it will touch upon all of them in some way.

Aquinas maintains that the first principle of natural law is - "do good, avoid evil". As he notes, that is a self-evident principle and obvious to all; if we want to be moral we should do good and avoid evil. No controversy here. The question is, of course, what is good and what is evil and how to we come to know which is which? Some think we can't know what is good and evil so the best we can do is live by the conventions of our times. Others think it best to let our passions be our guide to whatever we want to do. Others think only revealed religion can give us absolutes. These three positions capture the predominant views of our times.

Aquinas holds none of these positions. He argues that reason should be our guide to morality. Not only does he hold that the first principle of natural law, - "do good, avoid evil" is self-evident, he argues that there are other self-evident first principles, such as - "harm no man". These he says are imprinted in the minds of all by God; I believe other precepts such as - "provide responsibly for your offspring", - "give to each man his due" and - "seek knowledge" would qualify as precepts that Aquinas thinks all men know. Men (and I use the term generically here and throughout) may act against these precepts out of passion or because ignorance of some fact operative in a situation, but all would agree that such principles are moral truths.

Aquinas goes on to say that what he calls primary precepts of natural law are naturally and immediately known by man; he cites the 10 commandments as examples of these types of precepts. These precepts are justified by the primary principles. From the most general principle - "give to each man his due", from an understanding of what one owes to one's mother and father, it is clear that one - "should honor one's father and mother." Now this is not to say that one discovers the moral law by discovering these precepts in a deductive manner moving from the most general to the more particular. Rather, it seems that often moral discovery, as the discovery of other general truths, moves from the particular to the universal. That is, an individual could witness or participate in a transaction and quite immediately make the moral judgment that the act is good or bad. That is, for instance, an individual could witness someone honoring or dishonoring his parents and judge the action to be good or bad; from this action and others of the same sort one may come to formulate the - "law" that one should give each man his due. But it is because we already naturally know - in an unexpressed and unformulated way - that one should give each man his due, that we are able to see readily that honoring one's parents is good. Much in the same way that we, without musical training, can judge certain tones to be off pitch, we have moral - "perceptions" that some actions are good and some bad, without having any explicit training about such kinds of actions. I speak of these as moral - "perceptions" not because they are equivalent to sense perceptions, but because of their immediacy and their unformulated quality; indeed, I believe them to be rational in several important respects, not least because they are cognitive acts and they are in accord with reality.

Let me speak now about rationality and the Thomistic claim that - "one should act rationally." Indeed, one could formulate the first principle of natural law not only in the most basic formula - "do good, avoid evil"; in Thomistic terms, several formulas serve to express the same truth: for Aquinas, the following phrases are synonymous: - "act in accord with nature"; - "act in accord with reason" or - "act rationally"; - "act in accord with virtue"; - "act in accord with the dignity of the human person"; - "act in accord with a well formed conscience"; indeed, - "act in a loving way", properly understood, serves as well. While it would be of great profit to elaborate how each of these phrases is synonymous with the other, I want to devote most of my efforts here to explaining how - "act in accord with nature" and - "act in accord with reason" are synonymous and worthy guides to moral behavior.

First we must try to get as clear as we can what it means to say - "act in accord with reason" or - "act rationally". In our day, reason often gets a bum rap. This is a fault not of Aristotle or Aquinas but of Descartes and Kant and their followers. Since they retreated into the mind and abandoned the senses and emotions and nature as guides to truth, they made reason seem like something coldly logical, impersonal, abstract and completely devoid of experiential and emotional content. In their view, mathematics and geometry are seen as the quintessential rational acts; to be rational is to operate totally within one's mind and to be completely unemotional. Another view of rationality that dominates modern times is the view that only that which can be measured scientifically deserves any recognition as objective truth. No truths other than those substantiated by scientific proofs - truths that can be quantified largely in the laboratory - count as truth. No proof other than scientific proofs count as truth; only science and that which approximates to scientific truth is truly rational. Neither view is the view of reason and rationality held by the ancients and medievalists - those who defined the view of natural law I am defending here.

The ancients and medievalists did not think rationality was possible without the senses and the emotions for both are tools to reading reality; they provide the intellect with the material needed to make a good judgment. The etymology of the word - "rational" is rooted in the word - "ratio" which means - measure or - "proportion". One is being rational when one's thought and action are measured to, are proportionate with, or when one's thought and action correspond with reality (which itself is measured or governed by discernable laws; more about this momentarily). The thought that leads to acting in accord with reality is called rational. Now this thought need not be and perhaps only rarely will be the kind of abstract, cold, logical reasoning of a Descartes, Kant, or research scientist. This thought can be intuitive, creative, poetic, inductive, deductive, indeed, whatever human thought can be. It is all called rational thought not because it proceeds by syllogism or because it is subject to certain scientific tests; it is called rational because it corresponds with reality - and this includes all of reality, the spiritual and the transcendental as well as the logically provable and the scientifically measurable reality. Such thought cannot proceed without abundant data from our senses and our emotions. The intellect processes such data and orders it; it determines what values are important in the data and decides on the appropriate response. If one acts rationally, one then acts in accord with the ordering done by the intellect.

While the intellect should govern the emotions, it is not a natural law teaching that all rational behavior will be devoid of emotion. Again, the emotions can provide essential data to the intellect. Emotions that are well-habituated may lead one quite spontaneously to respond correctly to situations. One may spontaneously get angry at witnessing some act of injustice and, if one knows one's emotions to be well-ordered, one could respond quite immediately and correctly to the situation - and even angrily to the situation. Indeed, at times it may be an appropriate response to reality to rant and rave.

One doing so, is properly called rational, in spite of our common parlance. This talk of the mind and of rationality as something that is measured to reality suggests, as mentioned above, that reality is a thing that can be grasped. Natural law depends upon such. It rests upon the claim that things have natures and essences that we can know and correspond our actions to. There are many reasons for making this claim. One is the fact that things act in a predictable fashion; when we learn the properties of oil and water, for instance, we can predict certain things about their behavior. The fact that we build bridges which stand, that we make artificial hearts that work, that we put men on the moon, also indicates we are able to measure our thoughts to the external world and to act in accord with it.

Moreover, natural law operates on the premise that nature is good; that is, that the way things naturally are is good for them to be; it holds that the operations of things and parts of things contribute to the good of the whole. The wings of different birds are shaped in certain fashions because of the sort of flying that they must do to survive; different digestive systems work in different ways because of what is being digested. Indeed, natural law holds that the natural instincts of natural things are good; they lead them to do what helps those things function well and helps them survive. Since natural things have an order there is said to be a ratio or order to them; not one of which they are conscious but one that is written into their functioning. Natural law holds that we live in a universe of things that have a ratio to them and that we shall get the best out of these things if we act in accord with the ratio or nature that is written into them.

Now, man is a natural thing. He, too, has parts and operations and instincts that enable him to function well and to survive. Man differs from other creatures in that he has free will; that is, he can either cooperate with his nature or act against his nature, whereas other natural things have no such freedom. What enables man to be free is his reason, his rationality; he is able to weigh and measure different courses of action and to determine which actions are good or bad. According to natural law, those actions are good which accord with his nature and with the nature of other things. Since man is by nature a rational animal, it is good for him to act in accord with his reason. By acting rationally he is acting in accord with his own nature and with a reality that is also ordered. When he acts rationally, he acts in accord with his own nature and reality and in accord with the nature and reality of other things.

Now, let's get concrete. Let's talk about acting in accord with the nature of a few specific things. Take tomato plants, for instance. Tomato plants have a certain nature. In order to have good tomato plants one must act towards these plants in accord with their nature; one must water them, give them sunlight and good soil if one wants to produce good tomato plants. Such is acting in accord with nature in respect to tomato plants, such is rational behavior in respect to tomato plants. If one's tomato plants fail to produce tomatoes, one knows that one is doing something wrong; if one's tomato plants produce good tomatoes, one knows one is doing something right. Prof. Charlie Rice speaks of the rationality of putting oil and not molasses in the engine of a car. One needs to act in accord with the nature of things if one wishes them to perform well.

So now let us, moving quickly, move to human nature. If a human being wishes to function and perform well, what does his nature require of him? Let us begin with his physical nature. There is a considerable consensus about what makes for physical health and what is conducive to physical health. Those who don't get sick, who are able to function well in their daily activities, who are not overweight, we call healthy. We know how to produce such individuals. We are regularly and rightly advised to eat well, exercise regularly, and to get plenty of sleep. Those who do so generally flourish physically - because they are acting in accord with nature, with reason, and with reality. Psychological health is also understood to some extent; we know we need friends and rest and interests to sustain our psychological health; that is our nature; that is reality.

Nor are we in the dark about what makes for moral health or moral goodness. We recognize the goodness of the various virtues such as self-discipline, reliability, justice and fairness, kindness, truthfulness, loyalty, etc.; those who exhibit these qualities we generally recognize to be good - that is morally good - human beings. Parents who have children who display such qualities are rightly proud of them; their - "tomato plants" turned out well. So, in regard to sexual behavior, to sexual moral health, so to speak, what qualifies as acting in accord with nature, with reason? How do we determine what it is?

Now, for Aquinas, these are not difficult questions, though, apparently, they are extremely difficult questions for modern times. We are terribly confused about what proper sexual behavior is. College newspapers are filled with news of campuses that are devising codes of moral sexual behavior - codes that are designed primarily to stop or reduce the incidence of date rape on campus. These codes suggest, mandate, require - I am not certain what is the correct word - that in sexual activity neither individual proceed to the next level of sexual activity without obtaining the permission of the other individual. These codes reflect what has been the principle governing sexual behavior in modern times for sometime - whatever one feels comfortable with and whatever one agrees to is morally o.k. This is basically what we are teaching to our young people and they are doing much what one would expect given that teaching. As long as it feels good, and they have consented to it, there is no reason for them not to do - "it".

Is this working; is this principle leading to moral health or moral sickness? What can we say about the moral sexual health of our society? What does the fact that 68% of African-American babies are born out of wedlock suggest? The figure is now 22% in the white community and rapidly growing. This figure, of course, would be higher if it were not for the one and a half million abortions a year. One of two marriages is going to end in divorce. AIDS is decimating some portions of our population. Are there any hints here that we are violating nature, acting irrationally, failing to live in accord with reality? Are our tomato plants thriving?


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Catechism Part III

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