Two Bases of Morality in Catholic Theology

Robert T. Miller

There are nowadays at least two competing foundational concepts in Catholic moral theology. The first of these is the concept of human dignity, the intrinsic value of the human person, something the human person has simply by virtue of being a person. Because the human person has such intrinsic value, we are morally obligated to respect human nature, both in ourselves and in everyone else, and the content of this obligation is usually explained by saying that we ought to treat the human person always as an end and never merely as a means, especially never as a mere means to our own pleasure. The concept of human dignity appears in the writings of many contemporary Catholic philosophers(1) and theologians,(2) especially the writings of Pope John Paul II,(3) and even in some recent magisterial documents of the Catholic Church.(4)

That Catholic moralists would employ the dignity of the human person as a foundational concept in morality is somewhat surprising, for this concept, taken as the basis for an ethical system, arose not within the Catholic tradition but with the eighteenth-century German philosopher Immanuel Kant. Rational beings have dignity,(5) Kant says, and “are called persons inasmuch as their nature already marks them out as ends in themselves,”(6) and on this basis he formulates what he takes to be the supreme principle of morality: “Act in such a way that you treat humanity, whether in your own person or in the person of another, always at the same time as an end and never simply as a means,”(7) a principle that has come to be known in philosophy as Kant’s Categorical Imperative.(8)

The second foundational concept commonly used in Catholic moral theology is that of the final end for man. In a system based on this concept, human nature is seen as functional, that is, as being naturally well-adapted to perform certain kinds of activity to the exclusion of others. Human nature is a means well-adapted to a particular kind of end, just as submarines are well-adapted to travel undersea but not through the atmosphere and airplanes are well-adapted to travel through the atmosphere but not undersea. Human beings become morally good by subjectively choosing to make this objective natural end (called technically beatitude or happiness)(9) the ultimate purpose of all they do and by choosing actions that in fact achieve that purpose.

So what is the end for which human nature is a rationally well-adapted means? The Greeks, who thought about morality in this way, had various answers, but the best was that worked out by Aristotle in his Nicomachean Ethics. There Aristotle argued that human nature is well-adapted to rational activity, both theoretical and practical, in a community of friends: rational activity, because the ability to reason is what distinguishes human nature from that of other animals, and in a community of friends because human beings are social animals and need each other in order to engage in complex kinds of activity. The latter point is very important for morality: we can effectively perform the actions comprising our final end only in partnership with others, and so a man achieves his final end only as part of a community of men seeking that end together.(10) Hence, seeking our own final end requires us to will that others attain theirs as well, to not interfere with their doing so, and, as occasion requires, to assist them in their efforts.

An understanding of morality based on the final end for man was also becoming implicit in much of the wisdom literature appearing in the Jewish tradition in the centuries before the coming of Christ. Although the historical situation is complex, the understanding of morality in the Christian tradition from the very beginning at least until the Reformation has generally been based on the notion of a final end for man.(11) When St. Matthew relates Christ’s words in the Sermon on the Mount, the Greek text says that makarioi are the poor in spirit,(12) using the Greek word that Aristotle used to indicate those who most perfectly attained the final end for man.(13) Thus, the New Testament, written in Greek in a Greek-speaking world and following on the Jewish theological tradition in the wisdom literature, generally assumes that man has a certain final end that guides his moral life.

But wasn’t the Gospel radically different from earlier moral systems? It was indeed, but not in terms of the logical structure of the system: In the Gospel, morality was still about attaining the final end for man, but in the Gospel’s morality God elevates human nature through the grace of Christ and directs it towards a new, supernatural final end that radically surpasses anything unaided human nature could attain. In the Gospel, the new, supernatural final end for man is the vision of God that deifies man. Eternal life is this, to know you, the one true God,(14) and we shall be like him, for we shall see him as he is.(15) There is no question but that the ancient fathers understood the Gospel as speaking about a final end for man:(16) St. Ignatius of Antioch, for example, says that, by being martyred, he will truly live because he will obtain the pure light that makes him fully a man,(17) and St. Irenaeus says that the life of man is the vision of God.(18) Many of the other Fathers of the Church say similar things. Augustine’s famous Letter to Proba is all about attaining the final end for man, as understood in the revelation of the Gospel.(19)

And so on down the ages. When Thomas Aquinas wrote his Prima Secundae, the section of the Summa Theologiae that treats the foundations of morality, he begins with a treatise on the final end for man, and he ultimately explains that an action is morally right only if it (a) is capable of being a means to that end, (b) is in the actual circumstances in fact ordered to that end, and (c) is chosen by the agent for the sake of that end.(20) Aquinas was thus giving a particularly excellent account of Christian morality along very traditional lines. The theological manuals, the textbooks used in Catholic seminaries prior to the Second Vatican Council, followed similar lines. In fact, the manuals treated the Kantian system based on human dignity as an error to be refuted. Very significantly, although Pope John Paul II, as noted above, often uses the notion of human dignity in his non-magisterial writings,(21) when teaching magisterially on the foundations of moral theology in Veritatis Splendor, he relies heavily on the concept of the final end for man.(22)

These two concepts—the dignity of the human person and the final end for man—ground two different moral systems, a deontological one based on dignity and a virtue-theoretic one based on the final end for man. While the two systems often agree on what ought be done or not done in particular cases, they differ sharply on the meaning of moral terms and thus on the nature of morality itself. Any attempt to integrate the two is hopeless from a philosophical point of view: Kant expressly formulated his concept of human dignity as part of an express rejection of the concept of beatitude or a final end for man as a foundational concept in morals.(23) Attempting to reconcile the two systems would be like attempting to reconcile Stalinism with liberal democracy: the two are fundamentally opposed, and a person has to decide which he thinks is right.

For my part, I think there are overwhelming philosophical arguments against basing morality on the notion of human dignity. For example, using the concept of human dignity, the Catholic bishops of the United States have argued that abortion is incompatible with the dignity of the human person,(24) but secular moralists, using the very same concept of human dignity, have carried the day: in Planned Parenthood v. Casey, the United States Supreme Court concluded that “choices central to personal dignity,” including a woman’s choice to have an abortion, are protected by the Fourteenth Amendment to the United States Constitution.(25) That one and the same concept can be put to such opposite uses shows, I suggest, that the concept is disordered.

In particular, the concept of human dignity lacks definite content: It implies that we must treat others with respect, but it does not tell us which kinds of treatment are respectful and which not.(26) The formula that we must treat human beings always as ends and never merely as means is similarly empty. It does not justify any particular set of moral norms because it tells us nothing about what kind of treatment is consistent with treating a person as an end and not a mere means.(27) For that matter, it does not provide a clear account of what it means to say that we are treating a person as an end or a means. If I hire a prostitute to give me sexual pleasure, these moralists will say that I have treated her as a means, but if I hire a masseuse to give me non-sexual physical pleasure, they say that I have treated her as an end, for this latter transaction is morally licit. Whence the difference, since in both cases I have participated in a voluntary transaction in order that I have a pleasant sense experience? As far as I can see, the theologians who rely on the concept of human dignity have no basis to distinguish these cases.

In reality, the concept of human dignity gets what content it has precisely from the set of rules specifying which kinds of conduct with respect to the human person are permitted, which forbidden. Hence, these rules are logically prior to the concept of dignity, and so the concept cannot be used to justify the rules. The rules must be justified, if at all, on some other basis.(28) This was the procedure, incidentally, of the historical Kant, who seems to have understood the key concepts of his system better than his contemporary epigones in moral theology. Human dignity, standing by itself, can be used—and often has been used—to justify almost any moral judgment whatsoever.

When we turn to moral systems based on the final end for man, however, there is no difficulty in explaining how such a system justifies one set of moral norms rather than another. For, man has a final end because human nature, as known empirically, is well-adapted for some activities rather than others, just as oil-rigs, because of their natures, are well-adapted to removing oil from the under the earth, and pocket calculators, because of their natures, are well-adapted to performing arithmetic operations.(29) Because human nature is one way rather than another, certain activities rather than others constitute its final end; hence, a determinate human nature supports a determinate set of moral norms. Because not everyone will agree on what human nature is, there remains room for disagreement about cases, but there is no difficulty in explaining how a definite understanding of human nature—whatever that understanding may be—will generate a definite set of moral norms.

I could give other philosophical arguments against basing morality on the concept of human dignity, but, from a theological point of view, I find the historical arguments against such a system overwhelming. It is simply implausible—absurd, really—to suggest that the true basis of morality lies in a concept unknown until it was articulated in the eighteenth century by a German philosopher. Rather, there was a moral system whose key terms are found in the Gospels and books of the New Testament, a system that was clearly taught by the Fathers of the Church, that was carefully elaborated by St. Augustine and St. Thomas Aquinas, and that was expressly taught from Catholic pulpits, in Catholic catechetical texts, and in Catholic seminaries around the world until about forty years ago. This, surely, must be the correct account of morality.

The understanding of morality based on a final end for man thus seems superior, both philosophically and theologically, to the understanding of morality based on the dignity of the human person. Granted that this is so, why do so many contemporary theologians rely on the concept of human dignity? The answer, I believe, is that this concept, originating in modernity, is implicitly accepted today by almost everyone and is thus easier to rely on in popular contexts than the notion of a final end for man, which is foreign to the thought of late modernity. The use of the concept of human dignity, however, has not helped the theologians using it make inroads into a culture hostile to the Gospel, mostly because the concept, lacking definite content, can be used to justify almost anything, including the practices of the culture of death against which such theologians are often arguing. Surely, the culture of death is much stronger now than when theologians started using this concept about forty years ago. In any event, Christians have no license to use bad philosophy in the service of the Gospel. It is the truth, after all, and not what may seem rhetorically effective, that will set us free.

Robert T. Miller is Assistant Professor of Law at Villanova University.


(1) E.g., Robert P. George, In Defense of Natural Law (1999) at 96 (“Basic values … are intrinsic aspects of real and possible persons, their well-being and fulfillment. Were it otherwise, such values simply could not provide ultimate intelligible reasons for action.”). Similarly for others in the “New Natural Law” school.

(2) E.g., William E. May, An Introduction to Moral Theology (rev. ed. 1994) at 23 (using phrase “intrinsically valuable”). May also refers to a second kind of dignity that attaches to human beings when they make good moral choices, id. at 24; though arising from a different cause, this kind of dignity, like the first kind May mentions, is also a kind of intrinsic value.

(3) E.g., Love and Responsibility (William Collins Sons & Co., Ltd., trans., 1981) at 23; The Theology of the Body (1997) at 152 and passim; Crossing the Threshold of Hope (1994) at 196-203 and passim.

(4) E.g., Pope John Paul II, Encyclical Letter Veritatis Splendor (1993) at par. 48; Sacred Congregation for the Doctrine of the Faith, Declaration on Procured Abortion (1974) at par. 9.

(5) “That which constitutes the condition under which alone something can be an end in itself,” says Kant, “has not merely a relative worth, i.e., a price, but has an intrinsic worth, i.e., dignity.” Grundlegung zur Metaphysik der Sitten (1785), translated as Grounding for the Metaphysics of Morals (James W. Ellington, trans. 3d ed. 1993) at 435 (40) (References to Kant are to the standard pagination and then to Ellington’s pagination in parentheses).

(6) Kant, op. cit. at 428 (30).

(7) Id. at 429 (30).

(8) John Paul II expressly says in Crossing the Threshold of Hope at 201 that the principle that he himself relies on is a formulation of the Categorical Imperative: “Love for a person excludes the possibility of treating him as an object of pleasure. This is a principle of Kantian ethics and constitutes his so-called second imperative” (emphasis deleted). More accurately, the principle is the second formulation of the Categorical Imperative. See generally, Thomas Pogge, “The Categorical Imperative,” in Paul Guyer, ed., Kant’s Groundwork of the Metaphysics of Morals (1998) 189-213 (discussing various formulations of the Categorical Imperative).

(9) These terms must be understood in the technical sense indicated, not in their colloquial sense. Happiness here means performing those activities that constitute the human end, not some form of subjective contentment.

(10) See Alasdair MacIntyre, “Theories of Natural Law in the Culture of Advanced Modernity,” in Edward B. McClean, ed., Common Truths: New Perspectives on Natural Law (2000) at 91, 109.

(11) See generally Servais Pinckaers, O.P., The Sources of Christian Ethics (3d ed., Sr. Mary Thomas Noble, O.P., trans. 1985) at 191-215 for the relevant history of Catholic moral theology.

(12) Matt. 5:3.

(13) Nicomachean Ethics, lib. I, cap. 10, 1100a10-1101a20.

(14) John 17:3.

(15) 1 John 3:2.

(16) Pinckaers, op. cit. at 5 (“this viewpoint is basically in harmony with the Fathers of the Church”).

(17) Ad Romanos, cap. vi.

(18) Adversus Haereses IV, cap. 20, no. 7.

(19) Augustine, Epistle 130 (to Proba); see also De Trinitate XIII, cap. 2-3 and passim.

(20) Summa Theologiae Ia-IIae.18.1-11.

(21) See Love and Responsibility at 23; The Theology of the Body at 152 and passim; Crossing the Threshold of Hope at 202 (referring to “the principle that a person has value by the simple fact that he is a person”) (emphasis deleted). But see also “The Dignity of the Human Person” in Karol Wojtyla, Person and Community: Selected Essays (Theresa Sandok, OFM, trans., 1993) at 177, 179 (Human beings “live by means of things, always preserving their own purpose. This purpose is intimately connected with truth, because the human being is a rational being, and also with good, because the good is the proper object of free will. There is no way to acknowledge the dignity of the human being without taking this purpose and its thoroughly spiritual character into account.”).

(22) E.g., Veritatis Splendor, pars. 9, 10, 12, 72. But see also, e.g., par. 48, where there appears the notion of intrinsic value. The best that can probably be said is that John Paul II is often ambiguous about his understanding of the foundations of morality, but, when being most careful and teaching magisterially, he favors an understanding based on the final end for man.

(23) Grounding, op. cit., at 418-419 (27-29), 442 (46), 450 (51-52), 453 (54).

(24) United States Catholic Conference, Statement on Abortion, par. 3 (1969); see also, Pope John Paul II, Encyclical Letter, Evangelium Vitae (1995) at par. 90 and passim.

(25) 505 U.S. 833, 851 (1992).

(26) Some Catholic theologians explain human dignity in terms of man’s being made in the image and likeness of God. E.g, May, op. cit. at 23. If the thought here is that God has, say, infinite intrinsic value, and man, being made in his image, thus has some finite intrinsic value, then this move only compounds the conceptual confusion: infinite intrinsic value is a concept with even less definite content than intrinsic value and so cannot be used to explain it. On the other hand, if by invoking the image and likeness of God, such theologians are appealing to the fact that man has a rational human nature and thus a particular final end that fulfills this nature, then invoking the image and likeness of God amounts to jettisoning the concept of human dignity and adopting that of the final end for man.

(27) One strong indication that the argument in the text is correct is that, when attempting to justify particular moral norms, theologians who usually rely on the concept of intrinsic value switch to that of the final end. For example, in discussing certain objections to the Church’s teachings on sexual ethics, Pope John Paul II says, “since the human person . . . entails a particular spiritual and bodily structure, the primordial moral requirement of loving and respecting a person as an end and never as a mere means also implies, by its very nature, respect for certain fundamental goods.” Veritatis Splendor, par. 48. In other words, having a certain bodily structure, human nature is well-adapted for—i.e., has as part of its final end—certain kinds of bodily and sexual activities and not others. This is just the general doctrine that man ought to act for the sake of the final end appropriate to human nature as applied to the bodily and sexual aspects of that nature. Cf. Summa Contra Gentiles III, 122 (Aquinas’s argument against simple fornication). Saying, as the pope does, that all this is implied by “respecting a person as an end and never as a mere means” or that all this is to be understood “in the light of the dignity of the human person,” adds nothing. Veritatis Splendor, par. 48.

(28) Thus modern Kantians tend to focus not on the ends-means formulation of the Categorical Imperative but on the universalizability formulation (“I should never act except in such a way that I can also will that my maxim should become a universal law,” Grounding, op.cit. 402 (14)), which purports to identify which rules of conduct (“maxims”) may be acted upon, which not. But see Alasdair MacIntyre’s argument that even this formulation of the Categorical Imperative is vacuous because actions can always be redescribed in order to fall under a maxim that will pass the test imposed. Short History of Ethics (1966) at 197-198. If Kant is right that the two formulations of the Categorical Imperative are logically equivalent, this is just the result we should expect.

(29) See Peter Geach, Good and Evil, 17 Analysis 33 (1956), reprinted in Philippa Foot, ed., Theories of Ethics 74-82 (1967).


  1. Steve says

    Dear Mr Miller,

    With all due respect, I think you have misrepresented- and are therefore undermining- the Catholic teaching on human dignity. When Bl. John Paul II, for example, speaks of human dignity, there is an implicit- if not explicitly stated- assumption that this dignity comes from God, Who is man’s final end, and in Whose “image and likeness” we have been created; this, of course, implicitly refers to our final end, as we each possess rational, immortal souls.

    While Bl. JPII refers to treating people never as a means to an end as “a principle of Kantian ethics”, he is certainly not *deriving* this teaching from Kantian ethics, nor is he departing from Catholic Tradition, any more than he would be basing morality on Buddhism if he said, “The Golden Rule” is a principle of Buddhist ethics.” It is. But that is not the same as saying that the Christian principle is based on Buddhist ethics! He is merely emphasising a different aspect of man. Yes, many theologians refer to our final end when formulating/explaining theological principles, but by focussing on our God-given dignity without reference to our final end, Bl. JPII and others do not deny this essential element. If anything, Bl. John Paul II and others, by emphasising our intrinsic human dignity, provoke atheists and agnostics to consider some fundamental questions, like, “Is there a God?” “If I have dignity, where does it come from?” etc.

    Understood in the Catholic sense, human dignity and man’s final end are not different things; they are inseparable; however, Kant and other secular philosophers only appeal to the former, though without reference to God.

    • Josh says

      (I know I’m replying super late, but:)

      I mostly agree with you, Steve: a theologian must state the truth using the language of his times, and I think this is largely what JPII has done with the concept of human dignity. I recently heard a talk by Fr. Joseph Koterski in which he insisted that the “dignity of human life” (of which we often speak when opposing abortion) cannot be understood as something free-floating; rather, it is ultimately derived from our duty to love God as our last end. I would consider that to be an acceptable use of “human dignity”.

      Thus, as long as “human dignity” is understood to be just a formulation of our duty to love our neighbor, which is in turn derived from our love of God as final end, there can be no objection. Therefore, I agree with you that Mr. Miller is wrong if he is suggesting that “human dignity” ought to be banished from theological discourse.

      However, I do think Mr. Miller has a point in suggesting that “human dignity” can be a dangerous concept to use. When appropriating a concept foreign to Catholicism, there is always the danger of being misunderstood. It is therefore important to do what Fr. Koterski did, by carefully defining this concept in relation to traditional Catholic thought. (The human dignity of the Christians is not the human dignity of the Kantians.) Many theologians, however, seem very reluctant to refer back to man’s final end when discussing morality, hoping to pin all morality on a freestanding concept of human dignity. I think this is what Mr. Miller has hit upon in his essay, and he rightfully denounces it.

      Proof that this sloppy appropriation of “human dignity” can be dangerous? Well, several years ago as a poorly catechized Catholic, I was under the impression that Catholic ethics were essentially deontological and Kantian-ish. Had I encountered Aquinas’ ethics at that time, I would have likely thought them heretical. What caused the confusion? My exposure to the sort of theology that Mr. Miller denounces. Hence, the danger.

      So while I don’t think that “human dignity” must be rooted out as something incompatible with Catholic doctrine, I do think that we should be very careful when using it, so as not to give a false impression of what we believe.