Seriously, What About Cousin Marriage?

Justin E. H. Smith


Books consulted for this essay:

Sidibe John Boswell, Christianity, Social Tolerance, and Homosexuality: Gay People in Western Europe from the Beginning of the Christian Era to the Fourteenth Century. 8th Edition. University of Chicago Press, 2005.

Robin Fox, Kinship and Marriage: An Anthropological Perspective. Cambridge University Press, 1967.

Maurice Godelier, Les métamorphoses de la parenté. Paris, Fayard, 2004.

Lewis Henry Morgan, Systems of Consanguinity and Affinity of the Human Family. London, 1871.

Martha C. Nussbaum, From Disgust to Humanity: Same-Sex Marriage and Constitutional Law. Oxford University Press, 2010.

Andrew Sullivan, Virtually Normal. An Argument About Homosexuality. Vintage, 1996.

Göran Therborn, Between Sex and Power: Family in the World, 1900-2000, Routledge, 2004.


I recently spelled out some of the reasons why I remain doubtful about the prospects for transforming marriage, worldwide, into a gender-indifferent institution. (It is only the worldwide perspective that interests me.) I have not heard, in reply, any substantive arguments against the reasons I give for my doubts, and I have therefore decided that it might be a good idea to try one more time, and this time to make my call for serious engagement more explicit. I would sincerely like to know whether there is something I am missing.

I have been alarmed to see a sort of orthodoxy emerge as if out of nowhere over just the past few years (many of you will be old enough to remember when, in the not-so-distant past, Andrew Sullivan was condemned as a betrayer and a domesticator of the gay spirit for his powerful defense of same-sex marriage in Virtually Normal; I hope no one will try to tell me that everyone who condemned him at the time was, wittingly or un-, an enemy of human rights). This orthodoxy, like its opposite and indeed like all orthodoxies, presumes that any questioning of it amounts to hostility. There is no room in either of the prevailing orthodoxies that have formed around the controversy over same-sex marriage for someone like me: someone who supports marriage equality, but doubts, based on a thorough but admittedly incomplete reading of historical and anthropological scholarship, that the concept of marriage is in fact flexible enough to ever be transformed in such a way that marriage will cease to be heterosexual by presumption.

That is, I believe that we are right to decide to make same-sex unions equal before the law, but that it is not up to us to decide that the primary meaning of 'marriage' will cease to be 'basic unit of kinship, involving the monogamous pair-bonding of a male and a female'. This meaning will remain primary not only because other-sex couples are, as everyone agrees, statistically more common than same-sex couples, but because there is a fairly rigid system of organization in societies throughout the world that continues to be based on a presumption of gender dimorphism, and that continues to take cross-gender pairings as the elementary units of social reality. This is not what I want (I personally couldn't be less interested in 'defending' traditional marriage, though as it happens I don't think it's going to need defending), but rather what I believe to be the case.

I also believe that the movement for marriage equality misunderstands its contingency and ignores the historical forces that brought it into being. One of the triggers of my coming-out as a skeptic occurred a few months ago, when I happened to be speaking with a group of acquaintances who are also outspoken defenders of marriage equality. When quite unexpectedly the topic of first-cousin marriage came up, they began snickering like little boys: like little boys I might add, who in the not so distant past found mirth in every occurrence of the word 'gay'. This caused me to note that there is a certain selectiveness in what counts among educated Western liberals as 'doing the right thing' (a phrase we hear so often, and have heard most recently in connection with the legalization of same-sex marriage in Argentina).

Now the snickering might simply result from a lack of information; it might cease were they to learn that at present roughly 15% of marriages worldwide occur between first cousins. The eminent kinship scholar Robin Fox estimates that fully 80% of marriages in human history have been between either first or second cousins. In the Muslim world, first-cousin marriage continues to account for up to half of all marriages. Such marriage was always less frequent in Europe than in many other parts of the world, but its stigmatization only took hold in the 19th century (although two of my greatest heroes, who withstood that century's various prejudices fairly well, and who understood that human beings could be studied as products of nature, were both married to their own first cousins: Charles Darwin, and the founder of the science of kinship, Lewis Henry Morgan). Generally, the arguments in favor of exogamy were proferred by the same eugenic theorists who defended racial purity. Cousin marriage constituted one limit (too close), with racial miscegenation (too distant) at the other extreme. The ideal mating pool in the 19th century was the nation, ethnically construed, while both the extended family as well as those beyond the ethnie were held to pose a threat to the purity of the stock. Cousin marriage was consequently outlawed in most American states as part of the same wave of racial-purity laws in the decades following the end of slavery. Somehow, in the Civil Rights era no one thought it a priority to do away with these ungrounded laws against a form of endogamy, even as they rightly fought to reverse the laws restricting reproduction at the other end of the scale of perceived difference.

The scientific data on birth defects resulting from cousin marriage are various, with some studies showing that they are relatively more common in first-cousin marriages than in any random marriage, but no more common than in marriages that are already legal between people with certain high-risk genetic profiles. But in any case the question of health risks to offspring ought to be, by parity of argument, strictly off-limits, since one of the core arguments in favor of same-sex marriage is that, in our age, marriage has been decoupled from reproduction. You cannot coherently defend same-sex marriage against the argument that it can bear no fruit without outside assistance, while at the same time defending a continued prohibition on cousin marriage on the grounds that it produces defective fruit. First, the evidence suggests that its fruit is not particularly defective, and that the gross mutations that emerge from this variety of 'incest' are largely mythical, indeed fitting the pattern of monster mythology commonly associated with any prohibited sexual union. That is, talk of birth defects is much sooner a consequence of the prohibition on cousin marriage, than a reason for its prohibition in the first place. Second, if we really believe in decoupling procreation and marriage, then even if cousin-procreation does give rise to mutants, so what? Cousin-procreation must remain one issue, cousin-marriage another.

(Of course, there is also the question as to what's really wrong with real incest, which English-language moral philosophers for the most part refuse to touch, other than to insist without argument that it is wrong. They, like most of us, likely experience what Martha Nussbaum has called –in connection with homophobia– 'projective disgust' at the very thought of it, which suggests among other things that not all instances of such disgust are a sign of moral immaturity. The universal prohibition on parent-child incest is however much more useful for understanding what marriage is than moral philosophers ignorant of anthropology have been able to grasp, for it reminds us that, necessarily, kinship is structured by rules that cannot be justified in the available terms of moral-philosophical argument: if marriage is decoupled from procreation, and a father and a daughter really want to marry each other, there is no compelling argument in terms of rights and duties as to why they should not. But you can still rest assured we will not be doing away with the incest taboo any time soon.)

CS-Sidibe-03G So why, then, has the educated liberal Western elite taken up the cause of same-sex marriage so vigorously, even as it remains perfectly content to permit laws against cousin marriage to remain on the books throughout the United States? I think I know. It is because cousin sex is white-trash, Muslim, jungly, primitive: other, in short, in a way that gay sex –for heterosexuals who live in cosmopolitan urban centers in the West– is not. It would not be difficult to demonstrate that being at ease with homosexuality can often serve as a marker of social advancement for heterosexuals. There are likely more than a few arrivés in the big city who have left behind families in the Ozarks rich with multiple instances of kissing-cousins, who are more than ready to display their openness to same-sex couples, yet who discretely avoid mentioning the sort of family stories they left behind.

Now I am emphatically not saying that it is not a sign of moral progress for a former country yokel to relate with pride how, years ago, before arriving in the big city, he used to think that homosexuality was gross, but no longer does. I am saying that this sort of moral progress is also, at the same time, an indicator of a changing social identity, and this change is, in objective ways measurable by sociologists, a change upwards in the social hierarchy. No such upward motion can be enjoyed by displaying one's comfort with the idea of first-cousin marriage. I suspect that I myself run the risk of being taken down a notch or two in the hierarchy simply as a result of my decision to take this topic on.

The great difference in prestige of association with these two forms of kinship serves as a testament to the tremendous success of the political movement that traces its roots back to Stonewall, and in measuring up this success the only thing an honest person can say is 'good job'. But one may also ask, without compromising the spirit of heartfelt congratulation: Why this now, and not some other thing? What are the circumstances in which this particular social change is not only demanded, but comes to be seen as having universal validity, comes even to be spoken of in the language of human rights? Why is the family of the Indian groom –who is unable as a result of state-sanctioned anti-dowry campaigns to receive the traditional trousseau from his bride– also unable to take recourse to similar talk of rights, let alone of human rights? What about the villager who would like to enjoy some of the features of an Iroquois-type kinship system, but just happens to be born into a culture in which the Eskimo-type reigns supreme? And what about the agricultural laborer in China who wishes to marry her mother's brother's son, but is told by local functionaries (who are enforcing a ban on cousin marriage first effected in the name of 'modernization' and 'progress') that she cannot? Are her human rights being violated, or is she just unlucky to be born into a society in which the kinship rules do not match up with her desires?

One of the challenges that I've issued, which has yet to be answered, is for someone to come up with an example of an agrarian society in which same-sex unions had exactly the same social status and symbolic value as other-sex unions. In the absence of any examples to the contrary, I am going to go on assuming, first of all, that there is a link between modes of production and social organization, with kinship being the most basic form of social organization. I am going to assume, further, that marriage based on elective affinity is possible only given a high level of sociocultural complexity (which like it or not involves, inter alia, social stratification). Finally, I am going to continue assuming that wherever same-sex marriage is possible, it will be based on elective affinity rather than on the instantiation of socially determined kinship rules.

On these assumptions, it is not surprising to find that the examples of same-sex unions in the historical record come from small elites within very complicated societies: in particular, China in the first millennium BCE, and the Roman Empire. At the very apex of the latter, we find the satirist Juvenal commenting on a sort of same-sex wedding ceremony:

“I have a ceremony to attend,” quoth one, “at dawn tomorrow, in the Quirinal Valley.” “What is the occasion?” “No need to ask: a friend is taking to himself a husband; quite a small affair.” Yes, and if we only live long enough, we shall see these things done openly: people will wish to see them reported among the news of the day. Meanwhile these would-be brides have one great trouble: they can bear no children wherewith to keep the affection of their husbands; well has nature done in granting to their desires no power over their bodies. They die unfertile.

Now of course this is only one example, cherry-picked, as they say, from a Roman author famous for the very indiscriminateness of his derision. But still, it does seem representative of general social attitudes towards same-sex unions in the Roman world (in contrast with same-sex sex, which is a different matter entirely). For Juvenal, the event that is recounted is something to take in stride, even if it is also, evidently, a source of amusement. While there is no moral squeamishness about it, for him there does seem to be a conceptual difficulty in accepting that same-sex marriage could be fully marriage in the ordinary sense: even he, as a part of an urban elite in a stratified and complex society, takes marriage to be fundamentally tied to reproduction, and supposes therefore that a same-sex couple, to the extent that it is unfertile, can only approximate marriage. Beyond classical antiquity, there is even less to report. In his excellent book, Christianity, Social Tolerance, and Homosexuality, John Boswell identifies the venerable institution of adelphopoiesis or 'brother-making' as a sort of same-sex union in the early Christian, particularly Byzantine, world. Yet, as a scholar of great integrity, he is unable to find any conclusive evidence that such unions were ever anything more than 'spiritual'.

But, you might protest, why assume that we are bound to the past at all? Isn't the past really nothing more than a great storehouse of injustices? By way of anticipation, there is a familiar argument that I should probably address, and that goes something like this: the way institutions have been set up in the past can give us no guidance for the way things should go in the future, since many institutions that people used to take for granted have since been found out to be grossly unjust, and consequently were reformed or abolished. Take slavery, for example.

But there are two problems with the facile comparison between slavery and traditional kinship. One is that traditional kinship is underlain by real differences between men and women, whose distinct physiologies and life-cycles can only be ignored in very special circumstances, circumstances we enjoy but which others have not and still cannot enjoy, whereas there is no such difference that could possibly justify the enslavement of one group of people by another. Another problem with the comparison is that it invites repetition of the very failures of Abolition, to the extent that it again assumes that a change in law automatically brings about a change in reality. In a global sense it is not at all clear that some particular institution, 'slavery', went out of existence at some point in the mid-to-late-19th century. There is something of scientific interest to be studied in the way human groups tend to exploit other groups, perhaps naturally, even if we would really rather they stopped. This tendency cannot be properly studied if we assume that we successfully caused its extinction in the recent past when we made some –arguably superficial– changes to the laws that regulate the exploitation of a certain class of people in a certain region of a certain country. Mutatis mutandis, we are missing something of scientific interest if we do not distinguish between the desirability of changing law in favor of marriage equality, and the probable unchangeability of the primacy of heterosexual pairings in kinship systems throughout the world.

In sum, the comparison to slavery either involves an unwarranted assimilation of sex and race; or the comparison comes out in favor of just the sort of approach for which I am arguing here: one that distinguishes between what is desirable with respect to laws governing marriage, on the one hand, and, on the other, what systems of kinship for the most part in fact are. They are, notwithstanding what we would like them to be, principally systems for the transmission of inheritances, as Robin Fox soberly observes:

Kinship and marriage are about the basic facts of life. They are about 'birth, and copulation, and death', the eternal round which seemed to depress the poet but which excites, amongst others, the anthropologist… Death produces a gap in the social group and demands a replacement. Birth and parenthood provide an answer — provide an heir. The fact of there being two sexes with different functions, however, means that there are alternative means of deciding on who will be the heir.

Marriage is not about love, you romantic fools, it is about stuff. It is not an opportunity for individual fulfillment, and it is not the only context in which people, in history and in the present, have managed to have fulfilling or unfulfilling sex. It might someday be something other than what it has been and for the most part remains, but in order for this to happen we would have to witness, not a transformation, but a destruction, of traditional ways of life. Are you ready to say farewell to all that? I think I am, but I'm honestly not sure.

Again, in legal terms, nothing binds us to the past, if we don't want to be so bound. Yet we might find that social reality fails to fall into step with the commitment to equality of those who are currently in the process of shaping law, and when it fails to do so, we might ask ourselves whether this is not because kinship is still more tied to procreation for many people than we in the privileged West would like it to be, and whether in turn procreation is not still more rooted than we would like it to be in the sexual dimorphism that we have in common with a huge variety of other animal species.

We aren't married to the past, but let us at least admit that there is something curious going on when same-sex marriage, virtually unknown in the ethnographic and historical record, is hailed categorically in our own day as 'what is right' and as a 'human right', while by contrast first-cousin marriage, widespread in the same record, is first banned in the name of the horribly unjust and discriminatory pseudoscience of eugenics, and then permitted to remain under prohibition by the same people who claim to be so concerned about what is right. Let us admit that defense of same-sex marriage is not just about what is right, or about providing a final correction to an inherently good but hitherto flawed institution, but also about what is desired in a certain, very particular social and historical context, one in which an invitation to a same-sex wedding generally confers more prestige than an invitation to a backwoods ceremony at which there could be at most three sets of grandparents.

It has dawned on me that some people really just might not care about all of this, that they might not have any objections to what I've said, but simply find the broad-focused global historical perspective irrelevant in their pursuit of political goals. Some people are full-time activists, and not scholars, and that is fine. But there is still a reason why all of us, activists and scholars alike, might want to pay attention to the scientific study of kinship. The reason is that at present the enemies of marriage equality, thick-skulled though they may be, are nonetheless at least sharp enough to detect some of their opponents' weaknesses, and to exploit them. It is a weakness of the defenders of marriage equality that they have no response to the claim that 'marriage is between a man and a woman' other than to dismiss it, and usually in a tone so indignant as to warrant suspicion. It is a strength of the opponents of marriage equality that, in an important sense, their claim is true: it has the entire weight of history and anthropology on its side. It is true in roughly the same way as is the claim that 'adoption is of a younger person by an older person': a way that has nothing to do with the divine or moral order, but only with the real social need to lexically distinguish one sort of arrangement from another. What is needed, then, is for defenders of marriage equality to face up to this fact honestly, and to recognize that what they are calling for is exceptional in the course of human affairs, and will probably stay that way, even if this is by no means a reason not to keep pursuing it.

For an extensive archive of Justin Smith's writing, please visit

Photographs are from the exhibition, “Mon Village,” of the great Malian photographer Malick Sidibé.