Sex, Natural Law, and Confusion in High Places


The basis of Catholic sexual morality in natural law is widely known. Natural law itself, I suspect, is widely misunderstood. This may help to explain why Catholic sexual morality is widely rejected.

The basis of Catholic sexual morality in natural law is widely known. Natural law itself, I suspect, is widely misunderstood. This may help to explain why Catholic sexual morality is widely rejected. Natural law, of course, does not bind just Catholics, since it is accessible to reason unaided by faith, it directs us all to commit to the goods that are fundamental to our shared human nature. In Humanae vitae, Pope Paul VI appealed to natural law when he restated the traditional teaching that “each and every marriage act must remain open to the transmission of life.” While he distinguished between natural law and the revealed law of the Gospel, he said that both are “an expression of the will of God.” Consequently, we must faithfully observe both “to attain salvation.” He also said that divine revelation illuminates and enriches natural law.

I am not here concerned with dissent from the Pope’s teaching. I am concerned, rather, with profound misconceptions about the basis of the teaching. Specifically, I am troubled by the thinking of two highly educated, widely known, and much admired Canadian Catholics, whose published statements reveal an understanding of the natural-law defence of the papal teaching that is shockingly inadequate.

Mary Jo Leddy, formerly a Sister of Sion and a founding editor of The Catholic New Times, has been described as one of the most articulate Catholic women in North America. She discussed natural law and birth control during a 1991 dialogue later published as In the Eye of the Catholic Storm (Toronto, 1992). She said that when she was growing up she “never really encountered what people think of as the Church’s traditional teaching on marriage.” She later read about it in books and understood “there was a view of sexuality ... that you shouldn’t interfere with the process of nature.” During the birth-control debate of the 1960s, she raised the issue with her father, who was chief of staff of a large Catholic hospital and who conscientiously tried to follow Church teachings on medical ethics. He told her that “everything we do in this hospital interferes with the course of nature.” She never forgot that. The best in modern technology, she said, was challenging “the whole view of the natural law,” and such intervention made human life better. So it made no sense to people when the Church based its prohibition of birth control on the premise that “we can’t do things that interfere with nature.”

Mark MacGuigan, a judge of the Federal Court of Appeal and former minister of justice, was the founding dean of the University of Windsor’s Faculty of Law. He discussed natural law and contraception in his book Abortion, Conscience and Democracy (Toronto, 1994). At one point, he posed the question “Is artificial contraception wrong?” and responded with two further questions: “How, then, do we justify the use of drugs or prosthetics? How do we justify the use of creams or hair rinses or surgery to offset the effects of aging?” Christian teaching, he went on, has never generally held that what “just happens in nature is sacrosanct.” On the contrary, it has always recognized the improvement of nature through science, art, and healing to be “one of the highest human callings.”

Is the Church’s understanding of natural law as contradictory and naive as Leddy and MacGuigan suggest? After nearly two thousand years of experience and reflection, does the magisterium base Catholic sexual morality on the premise that we must never interfere with our biological or physical nature? That any intelligent Catholic should think so is disturbing. Even more disturbing is that neither Leddy nor MacGuigan is just any intelligent Catholic. Both have PhDs in philosophy, which they earned under Catholic auspices.

Basic Human Goods

Rightly understood, natural law follows from the first principle of ethics: good is to be done and pursued, evil is to be avoided. Good indicates a certain fitness, a sense of what ought to be, whether ethically or otherwise. Evil indicates the absence of good, but not just any good. It is the absence of a good that is supposed to be there. Evil is nothingness where being is required, where good is decreed. So we choose good even when we do evil, but good that is deficient, for it lacks something it ought to have. Speech is good even when we verbally abuse people. It is the abuse, the absence of required respect, that is evil. Evil, in other words, presupposes good just as error presupposes truth. You can conceive of a world without evil or error, but not of a world without goodness or truth. A world without goodness or truth is as inconceivable as a world without being.

By doing good and avoiding evil, we fulfil our human mandate. Unlike animals, which fulfil themselves instinctively, we do it, or fail to do it, intentionally. Because they act of necessity, animals are in no need of law; because we act voluntarily, we need it to enlighten judgement and strengthen resolve. Natural law directs us to act for, and never against, the goods we must participate in to effect our fulfilment. It forbids, for example, our deliberately sacrificing one of these goods to attain another. It prohibits, that is, our subscribing to the notion that a good end justifies an evil means. Such prohibitions are not alien strictures arbitrarily imposed from without; they are abiding principles that emerge from within to safeguard goods which are intrinsic to our deepest selves.

At stake are fundamental requirements of our personhood. These requirements or intrinsic personal goods are human expressions of being: life (its preservation, enhancement and procreation), which uniquely implements the unity, fullness, and fecundity of being; truth (knowledge), which articulates its intelligibility; community (friendship, patriotism, religion), which distributes its goodness; creativity (work, play), which manifests its beauty and energy. Through openness and commitment to these fundamental human goods, we engage in the profoundly personal task of determining ourselves, of choosing who we are.

To do good, then, is to act in such a way as to affirm and enlarge our human reality; to do evil is to act, or to fail to act in such a way as to deny and diminish it. Commitments at this level are open ended. We cannot set limits on life, truth, community, or creativity. We engage in them and in doing so fulfil essential requirements of our personhood, but we never exhaust them. In such an engagement, fulfilment is dynamic, never static. It means that fundamental human goods are being realized fittingly or as they ought to be, not that they have been realized once and for all. Who can say how much life, knowledge, community, or creativity is enough? We have no scale on which to measure such things.

We cannot, as individuals, commit ourselves to all of the fundamental goods and their variations; our limitations are such that we must carefully select what we engage in according to our talents and interests. But commit we must to a balanced range of human possibilities if we are to fulfil ourselves and be happy. To choose not to be involved at this level is to fail in the profound duty to realize our humanity, to refuse to actualize human goods that constitute our personhood, to settle for incompleteness. If we cannot commit to all basic human goods, we can and must respect and remain open to them all. We do this by refusing to violate any of them and by endorsing the fundamental commitments that other people make. It follows from the first principle of ethics that to refuse to commit to a balanced range of fundamental human goods is to sin by omission. To violate or act against such goods is to sin by commission.

The foregoing implies a moral distinction between the commission of evil, which is always forbidden, and the omission of good, which is often allowed. When we do evil, our conduct is active and direct: we intentionally assail what is good. Our will, in other words, is set against the good we violate. When we fail to do good or to prevent evil, our conduct is passive. We decline to act. The morality of such inactivity depends on circumstances, for we are obviously not responsible for all the good that does not get done or for all the evil that does. We are, however, responsible for all the evil we intentionally do, for the violations of basic human goods we deliberately undertake or approve.

The Goods of Sexual Union

The goods of marriage that natural law most clearly directs us to affirm and not deny are community and life. Marriage is not just a contract; it is a covenant. A contract can be broken. A covenant is irrevocable. The marriage covenant embodies the entire partnership, not just the sexual, social, or financial parts in isolation. But sexual union, the most intimate expression of human love, is central and unique, since it alone consummates the relationship and distinguishes it from other forms of friendship.

When spouses express their love through sexual intercourse, they celebrate the commitment they made to each other through their marriage vows. But sexual union is much more than celebration. It is a vibrant symbol of two lives in one that nourishes and sustains the marital union it symbolizes. It reiterates, physically and emotionally, the joyous surrender of two wills, the spiritual gift of one self to another, exclusively and permanently. It enfleshes the soaring language of love, repeating genitally the unconditional fidelity and generosity that the spouses have already expressed verbally. Not only does it nourish and sustain the marital union. It promises to enlarge the marital community. Through its unitive and procreative potential, the sex act renews the covenant, the irrevocable commitment that constitutes marriage, and renders it fruitful. (See John R Kippley, Sex and the Marriage Covenant: A Basis for Morality [Cincinnati, 1991 ]. Mr Kippley’s central claim is that God intended sexual intercourse to be a renewal, at least implicity, of the marriage covenant.)

Sexual union, in other words, is oriented to life, the common life of the spousal relationship--the community of love-and the new life that spousal devotion is apt to generate. Contraception militates against both. Since it most obviously affects the procreation of new life, I will deal with that first.

When we make love, or what passes for love, while contraceptively rejecting the possibility of new life, we act against life. But to act against life is to attack a fundamental human good, an integral aspect of personhood. When we contracept, whether mechanically, chemically or surgically, we sacrifice one fundamental human good in favour of another. For the sake of community, mutual love, fulfilment, pleasure, or whatever, we violate life. In the very act through which we are poised to co-operate in the transmission of life, we say no to life. By denying the procreative meaning of the sex act, even though we affirm its unitive meaning, we compromise its integrity. By rejecting one of the fundamental goods it uniquely and essentially entails, we render it incomplete. But incompleteness, the absence of a due good, is the definition of evil. Put another way, contraception violates the principle that the end does not justify the means. No matter how great the benefit to be achieved or the harm to be avoided, we are never justified in intentionally violating a good that is fundamental to what we, as persons, are and do.

Not only does contraception act against life. It undermines community, the total mutual self-giving that characterizes spousal love. As stated above, sexual intercourse renews the marital covenant. But if the renewal is to be fully effective, the spouses must express themselves genitally with the same unconditional self-giving with which they expressed themselves verbally when they exchanged vows. Unless they renew the covenant in the same spirit in which they established it, the renewal is seriously deficient.

Contraceptive sex is sex with conditions. Couples who engage in it make love with important reservations; they do not give themselves to each other completely, surrender to each other unconditionally. Each says to the other, “Take me, but not all of me. You can have me on condition that I withhold my fertility, my awesome power to transmit life, my unique link with the future.” Sex in these circumstances is not only deficient. In a sense it is unnatural.

Similarly, sex can be procreative, open to life in a human manner, only if it is unitive, immersed in self-giving love. To engage in sex solely to reproduce, to yield your fertility while withholding your affection, is similarly deficient and unnatural. We ought to make love, lovingly.

What this suggests is that when we separate the unitive from the procreative, we pay a steep price in human well-being. When we use contraceptives to eliminate the possibility of new life, we adversely affect our existing lives. For the unitive and procreative meanings of the sex act do not simply co-exist; they interpenetrate. To separate them is to diminish them. Each requires the other to complete itself. To engage in sex without being open to reproduction is to detract from the unitive meaning, which remains unfulfilled in the absence of total mutual self-giving. To engage in reproduction without sex, as technology now allows us to do, is to detract from the procreative meaning, which is dehumanized in the absence of spousal union, for children ought to be conceived in love. Love and life are what sex is essentially about. To separate them, to exclude one or the other, is to strike at its very essence, to corrupt its essential meaning. We should expect then to see a weakening of conjugal commitment where contraceptive use is common, where the act that uniquely renews the marriage covenant is severely and widely compromised: more infidelity, more divorce, more family trauma, more non-marital unions.

To sum up, natural law is about affirming or denying fundamental human goods. It is not about intervening in nature. We do not judge the morality of our actions according to whether they affirm or deny natural states or processes. Rather, we judge the morality of our interventions in natural states or processes according to whether we affirm or deny essential human goods. When we contracept, we act against the fundamental human goods of community and life. This we cannot morally do.

Natural Family Planning

MacGuigan suggests that contraception and natural family planning are morally equivalent. He points out that the relation between sexual intercourse and conception is “one of mere possibility.” If this is never to be interfered with, he says, we must also disallow natural family planning, “because the purpose of its use is to reduce the possibility of conception to zero.” And again, “There is no difference between the intention of a couple using artificial contraception and that of one taking advantage of natural infertility.”

True, the end, the avoidance of conception, is the same. The means, however, are different. It is one thing to close oneself to life by deliberately trying to prevent conception; it is quite another to remain open to life while avoiding the times when conception is likely to occur. As previously noted, there is a moral difference between the commission of evil, which is always forbidden, and the omission of good, which is often allowed. To repeat, when we do evil, our conduct is active and direct; we intentionally assail a fundamental good. This is how it is when we contracept. When we decline to do good, our conduct is passive and indirect; we intentionally abstain from an act through which we might have realized a fundamental good. This is how it is when we avoid having intercourse on days we are likely to be fertile.

To prevent conception is to act against life; to avoid intercourse is not to act for life. Although we are always forbidden to act against fundamental human goods, we are not always obliged to act for them, if we have serious reasons not to. Truth is an essential good that we act against when we lie, but not necessarily when we withhold information by not speaking. There are times when it is prudent not to speak or otherwise communicate, just as there are times when it is advisable not to have intercourse; but when we do communicate, we must not lie and when we do have intercourse, we must not deny the possibility of new life. Even though we do not seek it, we must remain open to life and ready to accept it if it comes unbidden.

MacGuigan concedes that for spouses to exclude the possibility of conception from all marital intercourse would be unchristian. He recognizes the inseparability of the unitive and procreative meanings of conjugal love, but in relation to the total life of the couple. In other words, marriage, not every marriage act, should normally be open to the transmission of life. But this is like saying that it is ethical to lie habitually as long as we sometimes tell the truth, or to steal regularly from our employers as long as we make them money. We cannot justify actions that deny human goods through some kind of merger with actions that affirm them. The two kinds of action are contradictory and morally incompatible.

By enabling couples to physically express their love at will, artificial birth control was supposed to strengthen marriages. But the divorce rate rose as contraception gained wide acceptance. Whether or not contraception weakens marriages, it seems obvious that it has failed to strengthen them. Many couples are convinced that natural family planning strengthens marriages, in particular their own, and there is some evidence to suggest that they may be right.

John Kippley, president of the Couple to Couple League, estimates that Americans using NFP have a divorce rate of only two to five percent. He bases the estimate on the experiences of more than 900 NFP teachers who worked with the league for over twenty years (see Fidelity, December 1992). Nona Aguilar found a divorce rate of less than one percent in a group of 164 men and women who had learned NFP during or prior to their marriages. They were geographically diverse and had widely different educational, social, and religious backgrounds (The New No-Pill No-Risk Birth Control, [New York: 1986]).

It could be argued that NFP does not strengthen marriages, rather the qualities that strengthen marriages predispose couples to use NFP. Lasting marriages depend on self-sacrifice, discipline, and responsibility. So does periodic abstinence. Spouses in deeply troubled marriages may not communicate well enough to learn, let alone use, NFP. Nevertheless, the advantages of natural over artificial birth control might motivate couples to cultivate the qualities necessary to sustain both the method and the marriage.

Natural Law Versus Experience

Some, no doubt, will protest that my conception of human nature and natural law is static and ahistorical. It is fashionable to point out that the experiences and perspectives of the time in which we live condition everything we know. If so, to hold that philosophical and moral conclusions can be valid for all times, places, and peoples is to fail to take into account the tentativeness of historical consciousness. Now it is true that our ideas grow out of and reflect historical circumstances, but that is only part of the story. They also reflect the nature or essence of things, what things fundamentally are. To the extent that they do, our ideas remain valid for any historical period. History is about change; essence is about stability. Experience, which is what history records, can alter neither the substance of fundamental reality nor the character of the ideas and principles that emerge from it.

We are fundamentally rational beings, which means that we are subject to the reality of what it is to be rational and what it is to be a being. For us humans, subjection to this reality, not the accidental changes of history, is the basis of our liberty and our fulfilment. We are never freer than when we think and act according to what we fundamentally or essentially are. We are never more in bondage than when we think and act only according to the limited experience of our own age. Put another way, the truth (about what we are) will make us free.

This is not to deny the importance of history. Although fundamental reality and our ideas about it transcend history, the ideas and the principles associated with them emerge through history. History is the means by which we acquire and deepen our knowledge of that reality. Through time and experience, we gain new insights into the permanence that underlies all the changes. When we look to tradition for guidance, we are not necessarily seeking solutions in the past. Insofar as we focus on ahistorical reality, we are seeking them in the eternal present. There can be no doubt that history conditions our consciousness; it does not determine it.

The dispute about the significance of history arrays persons against principles, love against law, time against eternity, becoming against being. John Giles Milhaven in Toward a New Catholic Morality (Garden City, 1986) talks of “the empirical tenor of contemporary thinking. We westerners, he says, have become “increasingly preoccupied, even obsessed,” with our worldly experience, suspecting any thesis about what and who we are that we cannot verify empirically. Morally, therefore, we tend to focus not on precepts but on “good experiential consequences,” personally and communally, not on upholding eternal principles but on loving persons, here and now. Experience, not essence, tends to become the ultimate test of what is good for us.

Much good has come of this. When we are conscious of people’s experience as distinct from their essential constitution, we are likely to be more sensitive to their hopes, fears, tragedies, and triumphs. If we understand what they are going through as distinct from what they are, we are likely to be more compassionate when they are in distress and more forgiving when they sin. We strive to alleviate suffering, whether from poverty, inequality, illness, or war, and in many commendable ways we emphasize the positive over the negative in the ethical injunction to do good and shun evil.

Much bad has come of it as well. As we grow increasingly “obsessed” with experience, we tend to lose sight of essence and the principles it supports. How we feel tends to take precedence over what we might know. When it comes to a choice between rights and duties, we choose rights because they feel better. Self-expression seems more attractive than self-control even though, paradoxically, we cannot realize our potential for self-expression unless we practise self-control. Self-indulgence seems more fulfilling than self-sacrifice, even though, paradoxically, in the long run self-indulgence is limiting and self-sacrifice liberating. Where experience is paramount, it is difficult to defer gratification, to embrace short-term pain for long-term gain, to make the hard decisions the human condition demands.

It is not, however, a question of either/or. I see no conflict between permanence and progress, between endorsing the absolutes at the root of reality and accepting the relativities of history, between proclaiming eternal verities and welcoming temporal experience, between adhering to principles and loving persons. Change presupposes stability; progress, permanence; history, a subject of history; human experience, human beings. It is the reality of what we are that determines the goodness of what we experience.

In other words, essence precedes experience, which is morally good only if it is in harmony with the fundamental goods that are intrinsic to our deepest selves. It makes no sense to focus on “good experiential consequences” in defiance of the elemental goods we humans must participate in to fulfil ourselves. It is these goods that determine whether the consequences are acceptable, not the consequences that determine whether we may violate the goods. Since the fundamental human goods are qualitative aspects of our personhood and therefore immeasurable, we have no way of ranking them. That is why we may never intentionally sacrifice one for the sake of another, let alone for any lesser good, no matter how compelling the evidence or how beneficial the consequences. This is not to deny the value of authentic human experience and the relevance of history. It is rather to mark the limits of experience and history.

Experience is subjective. That is why it appeals more to the heart than to the head and spurs us to action. When it prompts us to struggle for good and against evil, it makes for a better world. But by itself, experience cannot decide good and evil. Only reason can. Strong convictions may arise from experience, but this does not mean that they are sound. We have to examine them in light of the principles that protect the fundamental human goods.

Because it is subjective, experience is incommunicable. Even when we share the same experiences, we do not always form the same attitudes with respect to them. To evaluate the feelings and attitudes our experiences provoke, we have to rise above them. Just as experience can alter feelings and attitudes and provide a basis for action, the principles we commit to can shape our experience. When in light of reason or revelation we judge morally, we may feel compelled to change our experience, develop new attitudes and outlooks, and act differently. In a sense, essence is a part of experience: we experience the attraction of the fundamental human goods.

Not all experience is authentic. Many of us derive our unreflective moral attitudes from unbalanced or ideologically driven pseudo-experience provided by the news and entertainment media. Vice is more newsworthy and often more entertaining than virtue. Consequently, the sex and violence dispensed daily by radio and television, newspapers, periodicals and books, and the fine and performing arts can influence us more than the real experiences we live through. Time and again, these media present evil in such a favourable light that our unreflective sympathies lie with adulterers, home wreckers, swindlers, liars, and even murderers. Through television dramas and movies, we can daily experience the excitement of uncommitted sex, but not so often the emptiness, let alone the lasting effects of unintended pregnancy, sexually transmitted disease, and marital decline. Through unchallenged propaganda in favour of hedonism, feminism, environmentalism, liberalism, or whatever other ideology is in vogue, we can experience the exhilaration of revolution and the promise of utopia, but not so often the limits of the human condition, let alone the tragic consequences when we consistently violate them.

Utopians consider nature or essence limiting. They are correct. Although we might covet divinity, we have to settle for humanity. The limits of the human condition, however, are neither oppressive nor stultifying. Within them, we are free to do what is right and to create what is good. But right and good are unlimited. Consequently, although we possess only that measure of freedom and creativity appropriate to our nature, we constantly transcend our nature. We are limited, but certainly not predictable. No a priori inspection of human nature could have foretold democratic capitalism, human flight, near instantaneous worldwide communication, genetically engineered food, organ transplants, and a host of other systems, capabilities, inventions, products, and technologies we now take for granted. From a limited base, we contemplate a virtually unlimited future. Although human nature is static, human persons are dynamic. Because we participate in the fundamental human goods, which are inexhaustible, we transcend our static nature through dynamically fulfilling it. We creatively determine not natural law but ourselves in accordance with natural law.


Campbell, Joe. “Sex, Natural Law, and Confusion in High Places.” The Canadian Catholic Review (September 1997): 16-22.

Permission to republish granted by The Canadian Catholic Review.


Joe Campbell, a frequent contributor to The Review, is a freelance journalist with wide experience in radio, television, and publishing. His most recent article was “Another Look at the Death Penalty” (Nov 1996). His book The Glory of Gender: How We Differ and Why It Matters was published by WinstonDerek, of Nashville and Montreal in 1997.

Copyright © 1997 Canadian Catholic Review

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