This article appears in the May 2005 edition of the Catholic Medical Quarterly

The Impossibility of Same Sex Marriages

William E. May

The Gay Case:
Need For An Intelligent Answer

Advocates of same sex marriage commonly assert that its opponents are intolerant bigots unjustly denying a fundamental human right to individuals attracted to persons of the same sex. They maintain that same-sex couples can live in a committed relationship and have a right to express their affection for one another genitally. Many such couples claim that they can satisfy their sexual urges and natural inclination toward intimate union adequately only by establishing a more or less permanent relationship that includes sexual intimacy. (1)

They emphasize that the actual capacity to generate children is not necessary for a valid marriage; after all, opponents of same-sex marriage acknowledge the validity of the marriages of men and women known to be sterile and hence incapable of having children. Why, then, can they not recognise as valid marriages the union of same-sex who love each other and wish to share their lives together?

Intelligent replies must be given to the challenge these considerations raise. 1 hope to do so here by contrasting marriage and the marital act with same-sex unions and homosexual acts. In doing so I will show that homosexual acts are bad because they violate the good of the persons who engage in them.

I will conclude with an argument to show why same-sex persons simply cannot marry. Marriage is not a merely instrumental good, in the service of procreation, as St. Augustine thought, (2) or of pleasure, as same-sex advocates such as Steven Macedo maintain. (3)


A Fundamental Human Good

It is, rather, an intrinsic, basic good of human persons precisely as males and females, and as such it offers married men and women a reason to engage in the marital act. Vatican Council II indicated this great truth when it declared: "God did not create the human person as a solitary being" and, after citing Genesis 1: 27, "male and female he created them," explains that the companionship of the two sexes "produces the primary form of interpersonal communion. For, by their innermost nature human beings are social, and unless they relate themselves to one another they can neither live nor develop their gifts." (4)

Commenting on this passage, Germain Grisez notes: "This gloss on Gn. 1.27 implies that marriage is not merely an instrumental good: the companionship of man and woman belongs to humankind as image of God and is the primary form of one of the essential, intrinsic aspects of human fulfilment." (5) Moreover, Pope John Paul II clearly teaches in Veritatis splendor that "the communion of persons in marriage" (violated by every act of adultery) "is a fundamental human good" (nos. 13, 48; see also nos. 50, 67, 78, 79).

Marriage is consummated by the marital act, which is far more than a mere genital act between a man and a woman who happen to be married. Men and women are capable of having genital sex because they have genitals, and thus fornicators and adulterers are able to have genital sex. But fornicators and adulterers are not capable of engaging in the conjugal or marital act precisely because they are not married, and it is marriage that capacitates spouses to engage in the marital act, ie. to do what spouses are supposed to do, to become literally one flesh in an act whereby the husband personally gives himself to his wife by entering into her body person, and in doing so receives her; and whereby the wife personally receives her husband into her body person and by doing so gives herself to him.

Fornicators and adulterers cannot give and receive each other bodily; rather they lend themselves and their bodies to one another. The Church consistently and correctly refers to the conjugal act as one "proper and exclusive to spouses"; genital acts are hardly such.


An Act That Is Apt For Love And For Life

The marital act, moreover, is the kind or type of act intrinsically fit or apt both for communicating conjugal love and for receiving the gift of life. (6) This act is and remains a procreative kind of act even if the spouses, because of non-behavioural factors over which they have no control, for example, the temporary or permanent sterility of one of the spouses, are not able to generate human life in it. Their act remains the kind of bodily act in fact, the only kind of bodily act, "apt" for generating human life. (7)

In the marital act, moreover, husband and wife do not use their bodies as instruments to provide them with subjective states of consciousness but rather respect their bodies as intrinsic to themselves as bodily persons. When one trusts one's body as intrinsic to one's self, there is a unitary activity, and various bodily actions share in this activity since they are not directed to an extrinsic purpose.

In activity of this kind, as John Finnis says, the body's "activity is as much the constitutive subject of what one does as one's act of choice is." (8) Thus in the marital act, spouses freely choose to instantiate their communion of persons in one flesh open to the gift of life in and through an act in which their bodily activity is as much the constitutive subject of what they are doing as is their act of choice.

The union of husband and wife in the marital act "really unites them biologically (and their biological reality is part of, not merely an instrument of, their personal reality)...their (bodily) sexual union therefore can actualize and allow them to experience their real common good - their an intelligible common good even if, independently of the spouses' will, their capacity for biological parenthood will not be fulfilled by that act of gential union." (9) Their act, as John Paul II puts it, speaks the "language of the body." (10)

How different from this are same-sex unions and homosexual acts. In the precise sense homosexual act comprise anal or oral intercourse chosen by two males, with the intention that at least one of them achieve satisfaction by ejaculating within the other's body. Such acts are acts of sodomy or homosexual intercourse. A lesbian couple can, without engaging intercourse, stimulate each other to orgasm, and such intentional acts can also be regarded as homosexual in a broader sense.

And both male and female homosexuals may choose to masturbate each other as ways of expressing their affection. But are such acts truly "appropriate" means to do so? Do those engaging in them truly become "one flesh"? In such acts "is the body's activity as much the constitutive subject of what one does as one's act of choice is?" Or in such acts is the consciously experiencing subject using his body as an instrument extrinsic to himself?


Homosexual Acts Against Authentic Intimacy

In homosexual behaviour the bodily joining of the practitioners does not unite them biologically as one complete procreative organism. Although they may choose such acts as means of experiencing personal intimacy, the resulting experience is not and cannot be the experience of any real unity between them; it is not and cannot be the experiencing of a common good attained in and through an act of bodily union.

In such acts, each one's experience of intimacy is private and incommunicable, and no more a common good than is the mere experience of sexual arousal and orgasm. "Therefore," as Germain Grisez has said, "the choice to engage in sodomy for the sake of that experience of intimacy in no way contributes to the partners' real common good as committed friends." (11)

Homosexual and mutually masturbatory acts cannot do what those engaging in them may hope and imagine. Their activation of one or even each of the genital organs cannot be an actualising and experiencing of the marital good, as the conjugal act is. Such activation, as Finnis says, "can do no more than provide each partner with an individual gratification. For want of a common good that could be actualised and experienced by and in this bodily union, that conduct involves the partners in treating their bodies as instruments of their consciously experiencing selves."

Their "choice to engage in such conduct," he continues, "thus dis-integrates each of them precisely as acting persons." (12)

Persons choosing homosexual acts are not speaking the "language of the body," in which the body itself is integral to their union as bodily beings. Rather, they use their own and each other's bodies to provide subjectively experienced satisfactions, states of consciousness. Thus the body becomes an instrument used and the conscious subject the user. The conscious self is alienated from the body. The activation of their genital powers is done in order to bring about the satisfaction of a desire.

Thus to choose to engage in homosexual acts is to choose a specific kind of self-disintegrity. The self-integration damaged in this way is the unity of the acting person as conscious subject and sexually functioning body.

But, as Grisez points out, "this specific aspect of precisely the aspect necessary so that the bodily union of sexual intercourse will be a communion of persons, as marital intercourse is." Therefore, homosexual acts damage "the body's capacity for the marital act as an act of self-giving which constitutes a communion of bodily persons." To put this in other words, homosexual acts damage what Pope John Paul II rightly calls the "nuptial meaning of the body." (13)


Homosexual Acts Disintegrate The Body

Choosing to enagage in homosexual acts thus damages or violates the "nuptial meaning of the body" and thereby the capacity of the person to give himself bodily to another in marriage. But in addition, the specific kind of behaviour characteristic of homosexuals, anal intercourse, the sine qua non for male homosexuals." (14) endangers the health and therefore the life of its practitioners. As John R. Diggs, Jr., M.D. points out, human physiology makes it clear that the body was not designed to accommodate this activity. The rectum is significantly different from the vagina with regard to suitability for penetration by a penis... the anus is a delicate mechanism of small muscles that comprise `exit only' passage. With repeated trauma, friction, and stretching, the sphincter loses its tone and its ability to maintain a tight seal. Consequently, anal intercourse leads to leakage of faecal material that can easily become chronic...

The list of diseases found with extraordinary frequency among male homosexual practitioners as a result of anal intercourse is alarming: anal cancer, chlamydia trachomatis, cryptosporidium, giardia lamblia, herpes simplex virus, human immunodeficiency virus, human papilloma virus, isospora belli, microsporidia, gonorrhea, viral hepatitis type B & C, syphilis." (15)

This passage supports the conclusion that anal sex is hardly an appropriate way to express friendship. Added to the reasons already given to show how homosexual acts violate the nuptial meaning of the body and the unity of the human person as a bodily being, respect for the health and life of homosexual males ought to make one realize that anal sex, the characteristic kind of homosexual behaviour, is morally bad.


An Argument Against Same-Sex Marriages

Persons of the same sex cannot marry because they cannot do what married couples can, ie., consummate their union by a bodily act in which they become the common subjects of an act that, precisely as human behaviour, is eminently fit both for the communication of spousal love and for the generation of new human life. How would homosexuals consummate their union? How would they become "one flesh?" It is absurd to think that they become "one flesh" in anal or oral sex or by mutually masturbating each other. It is equally absurd to think that they can marry.


Homosexual Acts Against The Common Good

Moreover, equating same-sex unions with marriage would be a terrible injustice to married men and women, who perform an indispensable service to the common good of society. Genital coition is the only bodily act intrinsically capable of generating new human life. Kissing, holding hands, fondling, and ana/oral sex cannot generate children. They can be generated through acts of fornication and adultery, but it is not good for children to be begotten in this way.

For millennia every human culture has recognized the bond linking sex, marriage, and the generation of human life, and frowned on begetting children out of wedlock. Although many today think it fitting to generate children outside of marriage, the tragic situations accompanying phenomena such as fatherless children, undisciplined youth, and abandoned women show the shallowness of such thinking.

The marital union of a man and a woman who have given themselves unreservedly in marriage and who can consummate their union in a beautiful bodily act of conjugal intercourse is the best place to serve as a "home" for new human life, as the "place" where this life can take root and grow in love and service to others. A marriage of this kind contributes uniquely to the common good. It merits legal protection. Same-sex unions are not the same and sadly merely mimic the real thing. They can in no way be regarded as marriages in the true sense.


  1. See, for instance, Steven Macedo, "Sexuality and Liberty: Making Room for Nature and Traditions?" in Sex, Preference, and Family: Essays on Law and Nature, ed. David M. Estlund and Martha Nussbaum (New York: Oxford University Press, 1977), pp. 86-101 at. pp. 90-97

  2. "Surely we must see that God gives us some goods which are to be sought for their own sake, such as wisdom, health, friendship; others which are necessary for something else, such as learning, food, drink, sleep, marriage, sexual intercourse." De bono coniugali 9.9; translated by Charles T. Wilcox et al. in Saint Augustine: Treatises on Marriage and Other Subjects (New York: Fathers of the Church, 1955), pp. 21-22

  3. Steven Macedo, "Homosexuality and the Conservative Mind," Georgetown University Law Journal 84 (1995) 278.

  4. Vatican Council II, Pastoral Constitution on the Church in the Modern World (Gaudium et Spes), no,12

  5. See Germain Grisez, Living a Christian Life (Quincy, IL: Franciscan Press, 1993), p.557, footnote 5. Moreover, Gaudium et Spes speaks of marriage as "a community of love" (no. 48) and indeed as an "intimate community of conjugal life and love" (no. 49). On marriage as a fundamental or basic good see Grisez,pp. 553-569.

  6. Indeed, in Humanae Vitae Pope Paul VI declared: "Because of its intrinsic nature the conjugal act, while closely uniting husband and wife in the most intimate of bonds, also makes them fit (Latin text: eos idoneos tacit) to bring forth new life according to laws written into their very nature as male and female." Most English translations have "makes them capable"where I have "makes them fit," a translation more faithful to the Latin idoneos. On this see my essays. "La 'communio personarum' e Patto coniugale," in Morale coniugale e Sacramento della Penitenza: Riflessioni sul "Vademecum per i confessori" (citta del Vatican; Libreria Editrice Vaticana, 1998) pp 135-150; "Marriage and the Complementarity of Male and Female," in my Marriage: The Rock On Which The Family Is Built (San Francisco: Ignatius Press, 1995), pp. 48-49. See also Robert Joyce, Human Sexual Ecology: A Philosophy of Man and Woman (Washington, D.C.: University Press of America,1980), pp 63-85

  7. This is precisely the teaching of Pope Paul VI in Humanae Vitae, no. 11 where he affirms that "each conjugal act (matrimonii usus) must remain ordained in itself (per se aptus) to the procreation of human life." Here 1 translated per se aptus as "ordained in itself."Many English translations, made from the Italian, have "open to human life" for "ordained in itself." On this see Germain Grisez, Joseph Boyle, John Finnis and William E. May, "Every Marital Act Ought To Be Open to New Life: Toward a Clearer Understanding," The Thomist 52 (t988) 365-366. See also Roben George and Gerard V. Bradley, "Marriage and the Liberal Imagination, Georgetown Law Journal 84 (1995) 305.

  8. John Finnis, "Personal Integrity, Sexual Morality, and Responsible Parenthood" Anthropos: Rivista sulfa Persona e la Famiglia 1.1 (1985) 46.

  9. John Finnis, "Law, Morality, and 'Sexual Orientation," Notre Dame Law Review 69 (1994) 1066.

  10. See for example John Paul II, General Audience of January 26, 1.983: "The Language of the Body Strengthens the Marital Covenant," in John Paul II The Theology of the Body: Human Love in the Divine Plan (Boston: Pauline Books and Media, 1997), pp. 363-366

  11. Grisez, Living a Christian Life, p.653

  12. Finnis, "Law, Morality, and 'Sexual Orientation." 1067. See Patrick Lee and Robert George, "What Sex Can Be: Self-Alienation, Illusion, or One Flesh Union,: American Journal of Jurisprudence 42 (1997) 147.

  13. Grisez, Living a Christian Life, p. 650. At this point in his text Grisez is specifically addressing masturbation, but his analysis applies to homosexual acts as well. It is in note 190 on p. 650 that Grisez identifies the capacity violated by masturbatory and homosexual acts with the "nuptial meaning" of the body.

  14. Gabriel Rotello, Sexual Ecology: AIDS and the Destiny of Gay Men (New York; Penguin, 1998), p.92. Note that Rotello is himself an active homosexual.

  15. John R. Diggs, Jr. M.D., "The Health Risks of Gay Sex" (working paper, Corporate Resource Council, 2002, p.3.) In note 29, p. 12 Diggs provides the scientific sources for the list of diseases associated with anal intercourse: Anne Rompalo, "Sexually Transmitted Causes of Gastrointestinal Symptoms in Homosexual Men," Medical Clinics of North America 74.6: 1633-1645 (November 1990); "Anal Health for Men and Women," LGBTHealthChannel, "Safer Sex (MSM) for Men Who Have Sex with Men," LGBTHealthChannel

Reproduced from "Faith" volume 36 number 5, with grateful acknowledgement.