Indeed, Yoshino's posting brings to mind points developed in a recent paper by Yoshino's colleague at NYU, Professor Jeremy Waldron-one of the world's most eminent legal philosophers. Waldron observes that it "infuriat[es]" many of his fellow liberals that some intellectuals remain determined, in Waldron's words, "to actually argue on matters that many secular liberals think should be beyond argument, matters that we think should be determined by shared sentiment or conviction." In particular, Waldron laments, "many who are convinced by the gay rights position are upset" that others "refuse to take the liberal position for granted."

The central argument of our article is that equality and justice are indeed crucial to the debate over civil marriage law, but that to settle it-to determine what equality and justice demand-one must answer the question: what is marriage? So this is what the debate is ultimately about. In making our case for conjugal marriage, we consider the nature of human embodiedness; how this makes comprehensive interpersonal union sealed in conjugal acts possible; and how such union and its intrinsic connection to children give marriage its distinctive norms of monogamy, exclusivity, and permanence.

Our article offers detailed responses to the most significant objections to our view: that it has no principled grounds for recognizing infertile couples' marriages, ignores the needs of same-sex attracted people, is morally similar to support for anti-miscegenation laws, assumes the mutability of sexual desire, relies on religious belief, or fails to show the concrete harm in redefining civil marriage.

We also show that those who would redefine civil marriage, to eliminate sexual complementarity as an essential element, can give no principled account of why marriage should be (1) a sexual partnership as opposed to a partnership distinguished by exclusivity with respect to other activities (including non-sexual relationships, as between cohabiting adult brothers); or (2) an exclusive union of only two persons (rather than three or more in a polyamorous arrangement). Nor can they give robust reasons for making marriage (3) a legally recognized and regulated relationship in the first place (since, after all, we don't legally recognize or closely regulate most other forms of friendships).

We were explicit in framing these as challenges to proponents of gay civil marriage. And if anyone is capable of meeting them, surely it is Professor Yoshino. So his decision to pass over those challenges in perfect silence confirms and reinforces our belief (also amply defended in our article) that only the conjugal view can answer them.

If even that much of our article's argument is right, then the case against conjugal marriage laws as it is now being made in the courts collapses-and Yoshino knows it. If the logic of recognizing same-sex partnerships as marriages undermines the rational basis of the very idea of marriage as a sexually exclusive and monogamous union, then all but the most extreme sexual liberationists will draw back from his position. And if the same argument for radically reforming marriage policy also undercuts the point of legally regulating marriage at all, then it is self-defeating.

Instead of addressing these points, Yoshino grossly misrepresents two analogies we made as if they were identities. He thus represents us as holding what we do not hold and neither said nor implied (e.g., that infertile couples are just like losers in a baseball game; or that adoptive parents are not real parents).

But this exchange would be fruitless if we responded in kind. Instead, we will attempt to answer the concrete objections that seemed to motivate Professor Yoshino's essay.

At one point, Yoshino concedes that we have a "serious point," but he distorts it in a manner that works to the advantage of his own critique: "They are contending that sexual activity has been privileged over other kinds of bonding activities in determining who gets to marry." Notice the question-begging implication of the phrase "who gets to marry." Yoshino assumes (and assumes that we assume) that the institution of marriage inherently has nothing to do with sexual complementarity, and that we are merely supporting a historical tendency to "privilege" certain activities in determining who gets access to marriage (seen as a gender-neutral institution) under the law.

But as the very title of our article reveals, our goal is to show that the debate over civil marriage's definition is ultimately about what marriage is, considered as a pre-legal reality that the state has good reasons to track (and that it hurts the common good to obscure). We offer and defend an answer according to which bonds between two men or two women-like those among three or more-simply lack the features essential to marriage: what are denied legal recognition in these cases are not marriages in the relevant sense. To miss or misrepresent these points is to fail to engage our argument at all.

We give a coherent account of marriage as inherently a sexual partnership, one shaped by norms of monogamy and sexual exclusivity. We contend that any view of marriage that would include same-sex partnerships cannot defend these norms as a matter of principle rather than sentiment or preference, and we challenge revisionists like Yoshino to show-by arguments-otherwise. If Yoshino could have mustered effective arguments, he would have. But rather than propose an answer to the question What is marriage? he assumes an answer that he does not defend or even articulate, and uses it to impute to us groundless aggression: we are, he claims, "declaring war" on people's marriages; our arguments "demean" and "denigrate" those who cannot have biological children of their own.

Then has Yoshino "declared war" on the (according to Newsweek) 500,000 polyamorous U.S. households, by failing to support a policy that would ratify their romantic commitments as civil marriages? By this standard, no policy that proposed standards for which arrangements could be legally recognized as marriages-in other words, no marriage policy, period-would pass muster.

Professor Yoshino's rhetoric is thus, to all appearances, designed to exploit caricatures of conservatives as mean-spirited bigots out to thwart those not like themselves. But our argument is either successful or not. If it is successful, pejorative labeling cannot harm it; if it is unsuccessful, a clear explanation of its flaws-for example, by showing that it rests on a false premise or a fallacious inference-gives people all the reason they require for rejecting it.

Yoshino directs much of his scorn at an analogy we use to defend our view (and the view historically embodied in our law) that marriages, being comprehensive interpersonal unions, are consummated and uniquely embodied in coitus-in acts that extend spouses' union of hearts and minds along the biological dimension of their beings, much as various organs unite to form one body: by allowing them to coordinate together toward a biological function (in this case, reproduction) of the whole (in this case, the couple as a unit).

Like any analogy, the analogy of ours that Yoshino criticizes was meant to illustrate a limited point: how a community can derive its structure and defining norms from a certain end, even though it is valuable in itself and not merely as a means to that end. Here's how we put it:

A baseball team has its characteristic structure largely because of its orientation to winning games; it involves developing and sharing one's athletic skills in the way best suited for honorably winning (among other things, with assiduous practice and good sportsmanship). But such development and sharing are possible and inherently valuable for teammates even when they lose their games.

Just so, marriage has its characteristic structure largely because of its orientation to procreation; it involves developing and sharing one's body and whole self in the way best suited for honorable parenthood-among other things, permanently and exclusively. But such development and sharing, including the bodily union of the generative act, are possible and inherently valuable for spouses even when they do not conceive children.

Now law professors, like philosophers, are familiar enough with analogies to see that they break down: that is what makes them analogies and not equations, as we make clear in our article just a few sentences after drawing this analogy. One clear difference between marriage and a sport is that the latter is a competitive activity in which having winners and losers is inherent to the practice. Marriage is not. So our point was not to relegate spouses without biological children, or marital acts that (like all spouses' acts most of the time) do not cause conception, to the status of "losers" (who are then "denigrated" or "demeaned").

Professor Yoshino dismisses (without quite rehearsing) another one of our arguments-that only the conjugal view can account for the deep connection between marriage and children-on the ground that this argument relies on studies asserting the superiority of biological parenting without comparing it to same-sex parenting. But we never denied that there are not yet high-quality studies comparing opposite-sex to same-sex (or, for that matter, polyamorous) parenting. Here is what we did say about the connection between marriage understood as a conjugal union, and children:

We learn something about a relationship from the way it is sealed or embodied in certain activities. Most generically, ordinary friendships center on a union of minds and wills, by which each person comes to know and seek the other's good; thus, friendships are sealed in conversations and common pursuits. Similarly, scholarly relationships are sealed or embodied in joint inquiry, investigation, discovery, and dissemination; sports communities, in practices and games.

If there is some conceptual connection between children and marriage, therefore, we can expect a correlative connection between children and the way that marriages are sealed. That connection is obvious if the conjugal view of marriage is correct. Marriage is a comprehensive union of two sexually complementary persons who seal (consummate or complete) their relationship by the generative act-by the kind of activity that is by its nature fulfilled by the conception of a child. So marriage itself is oriented to and fulfilled by the bearing, rearing, and education of children. The procreative-type act distinctively seals or completes a procreative-type union.

[...]

Given the marital relationship's natural orientation to children, it is not surprising that, according to the best available sociological evidence, children fare best on virtually every indicator of wellbeing when reared by their wedded biological parents. Studies that control for other relevant factors, including poverty and even genetics, suggest that children reared in intact homes fare best on the following indices.

We cite some evidence suggesting that mothers and fathers tend to bring different strengths to the parenting enterprise. But we think that everyone in this debate should support rigorous studies designed to compare directly various parenting arrangements, and executed by teams of sociologists that disagree on the moral questions about sex and marriage, so that all are pre-committed to the results. We also expect, however, that few would take the sociological results as decisive on the central issue (what is marriage?), just as we did not in our article. But this raises a question: Does Yoshino deny that children deserve to be raised, wherever possible, by a mother and father-that this is worth promoting as an ideal?

Finally, having ignored our central arguments, made unwarranted linguistic associations, indulged in pejorative labeling, and studiously ignored every challenge we pose, Yoshino ends with a resounding declaration of victory: Even the best argument available against gay civil marriage fails, because it "denies" marriage to same-sex partners only by "denigrating" and "demeaning" the marriages of many opposite-sex couples. But Yoshino would be warranted in declaring victory only if he had given good reasons for rejecting our actual arguments, and provided his own answer to the central question of what marriage is. He did neither.

----Robert P. George is McCormick Professor of Jurisprudence at Princeton University. Ryan T. Anderson is a PhD Candidate in Political Science at the University of Notre Dame. Sherif Girgis is a PhD Candidate in Philosophy at Princeton University.