Like Andrew Koppelman, Barry Deutsch has posted a critique of our recent Harvard Journal of Law and Public Policy article arguing that marriage is the conjugal union of husband and wife. And, like Koppelman, Deutsch makes central to his critique a denial that marital coition effects a true organic (bodily) union of spouses. For the reasons we set forth in our reply to Professor Koppelman, we believe his critique is unsuccessful; but no reader will doubt that Koppelman engaged our argument with intellectual and moral seriousness. We cannot, alas, say the same for Deutsch’s reply. But we will respond to it without resorting to the rhetorical tactics Deutsch himself employs.

Deutsch’s central problem is with the following passage in our article:

In coitus, but not in other forms of sexual contact, a man and a woman’s bodies coordinate by way of their sexual organs for the common biological purpose of reproduction. They perform the first step of the complex reproductive process. Thus, their bodies become, in a strong sense, one—they are biologically united, and do not merely rub together—in coitus (and only in coitus), similarly to the way in which one’s heart, lungs, and other organs form a unity: by coordinating for the biological good of the whole. In this case, the whole is made up of the man and woman as a couple, and the biological good of that whole is their reproduction.

Deutsch follows this with an analysis:

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1) Individual adults are naturally incomplete with respect to sexual reproduction.
2) Reproduction can only be begun via coitus between a man and a woman.
3) Thus, during coitus, a woman and a man’s bodies are biologically united and become one flesh.

How does #3 follow from #1 and #2? Answer: It doesn’t.

Deutsch claims that our argument is a non sequitur because there is “no non-metaphorical sense in which the spouses become ‘one flesh’” in light of the fact that “the man and the woman … remain two separate entities,” as can be confirmed by a “DNA sampling.”

As most readers will have noticed, Deutsch’s claim against us is itself a non sequitur.

Deutsch evidently assumed that a man and woman’s common biological action cannot make them biologically united at all (that is, united in any respect), unless it makes them completely so (that is, united in every respect). But this is obviously untrue. Organic unity can be genuine without being all-encompassing:  two distinct organisms can be organically united in some respects or for some purposes while remaining separate and self-sufficient in other respects or for other purposes. Whether we are talking about humans or zebras, individual members of a mammalian species are separate and self-sufficient with respect to locomotion, digestion, respiration and most other functions. With respect to reproduction, however, individual members of the species are not self-sufficient. A male or female is half of a potential mated pair whose biological (and, as such, organic) common action—or unity—in coitus characteristically (though not on every occasion) produces offspring.

Deutsch’s appeal to “DNA sampling” to “confirm” that there is “no non-metaphorical sense” in which males and females organically unite in mating is risible. Genetic identity is not what constitutes biological unity (cf. identical twins)—nor is it, as we will show, even necessary for biological unity of every meaningful sort. Elsewhere Deutsch suggests that biological unity requires being “physically joined.” But physical joining just in itself can scarcely be considered a very significant kind of bodily unity, since it may well include the “unions” of animals that are tied to each other by the tails, or whose hides have been surgically attached at a point. There would be nothing metaphysically or morally significant about these instances of “physical joining.”

The rest of Deutsch’s posting is ostensibly an effort to find such a sense in which coitus is a real bodily union. But if he were careful, he wouldn’t have had to look very far. In fact, the answer is in the very passage that he first quotes: “…they are biologically united… similarly to the way in which one’s heart, lungs, and other organs form a unity: by coordinating for the biological good of the whole.”

Thus, following Aristotle, we argued in our article—in the paragraph immediately preceding the one that Deutsch cites—that “our organs—our heart and stomach, for example—are parts of one body because they are coordinated, along with other parts, for a common biological purpose of the whole: our biological life. It follows that for two individuals to unite organically their bodies must be coordinated for some biological purpose of the whole.” This conception clearly allows for partial biological unity, in respect of coordination toward some but not other biological purposes.

Think of a biological function in humans. Now think of the parts that are inherently oriented to playing some role in serving that function and can thus be said to be coordinated together toward its fulfillment. Our claim is that there is one meaningful sense in which the parts just mentioned enjoy a biological unity, precisely in virtue of that coordination toward fulfilling a common biological function.

If the function that you thought of was locomotion, metabolism, respiration, or one of many others, then (a) the parts that you thought of are organs within a single individual; and (b) the function in question itself plays some role in serving that individual’s biological life. But if reproduction was the function you picked, then (a) the parts that you thought of are not organs in a single individual; and (b) the function in question is one that serves the biological good not of an individual, but of a male-female pair as a whole: namely, their reproduction. And coitus is the process by which such coordination toward a common biological function—such real, if limited, biological unity—is achieved.

Deutsch objects that “it’s not true that every part of our body is ‘coordinated’… for a common biological purpose… [namely] biological life,” and cites hair, skin tags, and benign tumors. But far from disproving our point, these examples support it. For it is clear that hair, skin tags, and benign tumors—though contiguous with our bodies—are not biologically united with them in just the way that, say, a heart and lungs are. To remove tumors or skin tags (or at least some of the body’s hair) has no effect on our organic functioning; that is why doing so is not mutilation. (In Deutsch’s own words, “they could all be removed at no biological cost.”) If there is still a sense in which they are parts of one’s body—because of their contiguity with it, and so on—that just shows that there are different (more and less important) senses in which two things can be biologically united. But that is no strike against our argument, since we articulated precisely which sense we meant—and a sense that is clearly more significant than the contiguity that skin tags have as much as limbs do.

Deutsch continues:

I largely agree with George that a marriage, in nearly all cases, requires a physical, sexual union to become complete. (There may be individual couples who are exceptions, but for the overwhelming majority of couples, it will not feel like a true marriage without a sexual union.)

It is not clear what Deutsch means here. If marriage is a human good with some essential features that hold regardless of the participants, then either consummation is one such essential, or it is not. If it is, then Deutsch’s second sentence is false; if it is not, then his first sentence is puzzling. If, on the other hand, Deutsch thinks that there are no essential features of marriage that hold constant across would-be spouses, then we wonder why he thinks that marriage would require even mutual commitment (much less monogamous or exclusive commitment). Why, too, would he not think that such an intrinsically malleable good would be hindered by legal recognition, which imposes certain uniform constraints on every recognized marriage?

Perhaps then Deutsch means that a certain sort of mutual pleasuring is essential to marital unity, and that this is what most (but not all) couples achieve through sex. Our article includes a short note about why pleasure cannot be another biological good in respect of which two individuals are in some sense biologically united, by sexual activities other than coitus:

Pleasure cannot play this role for several reasons. The good must be truly common and for the couple as a whole, but pleasures (and, indeed, any psychological good) are private and benefit partners, if at all, only individually. The good must be bodily, but pleasures are aspects of experience. The good must be inherently valuable, but pleasures are not as such good in themselves—witness, for example, sadistic pleasures.

Ignoring our first two points, Deutsch says of the last sentence:

[That] is a little like saying “childbirth is not as such a good in itself–witness, for example, the birth of Hitler.” For any good, one could imagine an instance of the good being used for negative purposes; yet if “can never be used for negative purposes” is the definition of good, then absolutely nothing on this mortal Earth is or ever can be good. That’s silly. In the right context (i.e., not Hitler), childbirth is a good; and in the right context, sexual pleasure is also a good.

Our point was not that sadistic pleasures are inherently good things that just happen to be used for bad purposes. First, it is a confusion to speak of sadistic pleasures being used for bad purposes. It is the other way around: sadists seek what is bad or evil for the sake of pleasure, which they typically seek for its own sake. Second, we agree (who wouldn’t?) that good things can be twisted. Our point was that in sadistic pleasures, it is not as if the pleasure itself is good, only sought by illicit means. Pleasure taken in bad things is bad. And we doubt that Deutsch would disagree. If a man took pleasure in strolling the halls of a pediatric oncology ward to watch children die of cancer, no one would we say, “Well, it’s too bad that’s what suits his fancy—but at least he got pleasure out of it.” Pleasure does not have its own value, considered as a state of mind independently of its object; it shares in the moral quality of that object. Now communities—like friendship or marriage—are built up by the pursuit of what is inherently valuable. So marriage cannot be built up by the common pursuit of pleasure just as such. Spouses must achieve some good (organic union as an embodiment of their commitment), in which the pleasure they take is then an additional perfection. That was our point.

From these misunderstandings, Deutsch rushes to his conclusion:

But at heart, “What Is Marriage” is a faith-based argument. George believes, as a matter of faith (all he has, since he lacks evidence), that there’s something called “bodily union,” a biological merger of male and female bodies, that occurs only in coitus….

But basing laws on Robert George’s faith in a mythical “bodily union” is no better than basing laws on my faith in Mork from Ork. Robert George and his fellow-travelers may have faith in magical bodily unions, but they would be morally wrong to force that faith on us through the legal system….

But now we’re treading on even more bewildering territory. Do we want a society in which people’s civil rights are decided, not by what is just, not by what is pragmatic, not by what is fair, but by a metaphor? Metaphors, unlike facts, can change arbitrarily. Suppose that George chooses to believe in a different metaphor next year — a metaphor saying that comprehensive unity can only be achieved by dog owners, for instance. Would we then be obliged to change marriage laws to exclude cat owners?

Ridicule is the last resort of desperate arguments. If Deutsch had achieved a sound understanding of our view (as Koppelman did) and then produced a valid argument against it (as Koppelman made a serious effort to do), he would have had no need of putting words into our mouths (“biological merger”) or festooning his critique with dismissive terms (“mythical,” “magical”). A sound objection would have sufficed. But a dozen sneers do not make an objection.

What Deutsch calls the protean “myth” at the heart of marriage law has been its cornerstone for centuries. Our legal tradition understood coitus and coitus alone as consummating (and thus completing) a marriage, but never accepted infertility as a ground for annulment or dissolution. Our argument—into which readers will gain little insight by reading Deutsch’s post—can make ample sense of that tradition, in a way that also accounts for other marital norms (permanence, exclusivity, monogamy). Can Deutsch? What is the non-arbitrary basis on which he would ground these norms (assuming he accepts them), while rejecting sexual complementarity as integral to marriage? Our guess: he will do no better than other advocates of redefining civil marriage have done in meeting our challenge. What argument would Deutsch make against the 300 academics and activists who signed “Beyond Gay Marriage,” or others who would eliminate the requirements of monogamy and sexual exclusivity? Or would he join them?

The common biological action of mating is no myth; it is a biological fact. Ask any zoologist (or farmer). The real question is whether human mating, precisely in virtue of the unity it effectuates, is capable of having moral significance of a certain sort. Can it embody and complete an inherently valuable, comprehensive form of relationship—historically known as marriage—that is, like mating itself, ordered to procreation? We have argued as much. And if we are right, then not only sexual complementarity, but the other structuring marital principles recognized by our legal tradition—monogamy, sexual exclusivity, the pledge of permanence—are intelligible and sound. Yet they cannot be accounted for by a sneering Barry Deutsch any more than by a commendably thoughtful and morally serious scholar like Andrew Koppelman.