A. The Charge. The procreation standard was perceptively formulated by Plato in The Laws:“[T]his law of ours . . . permits sexual intercourse solely according to nature for the purpose of having children and forbids it with the male, wherein the human race is intentionally murdered, together with the sowing of seed on rocks and stones where it can never take root and produce new individuals.” The Laws, VIII 836 B-839 A; cf. 636 B-C ).
As Alfred North Whitehead remarked, all of Western philosophy consists of footnotes to Plato. That is certainly true in this instance.
B. Historical Background. It is commonly thought that a dour, restrictive view of sexual ethics is enshrined in the Hebrew Bible and the New Testament. Yet it is hard to find a clear statement to that effect in any of those ancient religious documents. In fact there is plenty of contrary evidence. Proverbs 5:15-19 encourages couples to enjoy sexual pleasure together within marriage. Even though he was conflicted about sexuality, the apostle Paul nonetheless says that husbands and wives should render the sexual affection due each other—refraining only during times set aside for prayer and fasting (1 Corinthians 7:3-5).
In fact the long-dominant religious arguments in favor of limiting sexual acts to those that can lead to procreation were created by Early Christian writers of the Patristic period, though they drew on their interpretations of the Septuagint and Philo of Alexandria. This amalgam of sex-negative views generally sheltered under the umbrella concept of “porneia” or fornication, which had highly negative connotations. Sexual promiscuity was stigmatized by linking it with heathen rites, termed "spiritual adultery." Philo, Tatian, and Clement reinterpreted Paul’s conflicted thoughts, giving them a restrictive emphasis and blending them with Platonic analyses of desire. Yet Clement's contemporary Epiphanes focused more on Platonic and Stoic communal sexual ideals.
Thomas Aquinas (Summa Theologiae, II-II, q. 154, 11) rejects bestiality, homosexuality, and “unnatural” heterosexual intercourse as departures from the proper species, the proper gender, and the proper organ(s) respectively. How was this concept of propriety--or finality as it is called in some recent Vatican documents--determined? Such a neat scheme does not derive from the Bible, which in its formative stage (the Hebrew Bible) is innocent of the concept of nature and the unnatural. It must depend on an overarching concept of teleology, that is say, the assumptions that the universe works towards some great and final purpose; that this purpose has been worked out in every detail; and that moreover it is perfectly accessible to human reason. Yet modern science rejects such a teleological worldview.
Hovering in the background of the procreation standard appears also to be a simplistic folk notion that each organ must have a single basic function to which others may be added only at one’s peril. Yet the genitals already serve two purposes - elimination and copulation - why not then the anus? As the Marquis de Sade pointed out long ago, if Nature truly wished to forbid anal intercourse, she would have placed the orifice in a position that render it inaccessible to the erect penis.
Defenders of the procreation-only thesis must also cope with the habits of kissing, caressing, and other types of foreplay which, although they have traditionally been accepted as licit, in no way permit procreation in and of themselves. (It is revealing of the debt of Freudian psychoanalysis to religious tradition that it has sought to consider “unnatural” acts acceptable only if they lead to and enhance coitus, with its procreation potential.) There is also, of course, the matter of contraception and birth control. In fact the play element in culture has always held an important place in heterosexual behavior even as narrowly defined by Aquinas; to attempt some tortuous scheme for excluding it under some conditions and permitting it in others is special pleading.
In recent discussions concerning same-sex marriage opponents have advanced a version of the procreation argument. According to law professor Dale Carpenter (who is critical of this view), it can be stated this way: “Procreation is indispensable to human survival. Marriage is for procreation, and procreation should occur within marriage. Procreation is the one important attribute of marriage that supplies the male-female definition. Gay couples can’t procreate as a couple, so gay couples shouldn’t be allowed to marry.”
Gay-marriage advocates respond as follows. Since procreation has never been required for marriage, the premise that “marriage is for procreation” is wrong, or at least incomplete. Sterile couples, old couples, and couples who simply don’t want to procreate are all allowed to marry. No-one objects to their marriages, so no-one should on this ground object to same-sex marriages. Opponents of gay marriage have attempted to respond to this point, but their arguments have not carried conviction.
C. Response. Narrow procreation-only standards do not hold up for one simple reason. Society has always permitted sexual relations between two persons who cannot have children, whether because of impotence, injury, or advanced age.
BIBLIOGRAPHY. John T. Noonan, Jr., Contraception: A History of Its Treatment by the Catholic Theologians and Canonists, Cambridge: Harvard University Press, 1965; Michel Foucault, The Use of Pleasure (The History of Sexuality, Vol. 2), New York: Pantheon, 1985; Kathy L. Gaca, The Making of Fornication: Eros, Ethics, and Political Reform in Greek Philosophy and Early Christianity, Berkeley: University of California Press, 2003.