Kinship is inherently about configurations of sameness and difference, inclusion and exclusion. Yet theorists have often focused on kinship’s capacity for marking the inclusiveness of group formation, whether this be through shared substances, shared norms of conduct, and/or shared affect—variously configured as ‘amity’ (Fortes 1969), ‘diffuse enduring solidarity’ (Schneider 1968), and ‘mutuality of being’ (Sahlins 2011a, 2011b). As Donna Haraway (1997: 53) maintains: “Kinship is a technology for producing the material and semiotic effect of natural relationship, of shared kind.” But kinship is also a technology for the production of differences, exclusions, and non-mutualities (Franklin and McKinnon 2001; Goldfarb and Schuster 2012, this issue), and these have been less well-integrated into a general theory of what kinship is, means, and does.
However, there is one way in which difference has always been integrated into the theory of kinship—that is, in the core distinction between consanguinity and affinity. Within the overarching frame of kinship, consanguineal kin have been assumed to be of ‘shared kind’, while affinal kin have been conceptualized as somehow different (Sahlins 2011b: 235). Affinal kin are from ‘other’ groups—even enemy groups—who share neither a substantial nor an affective sense of mutuality, or they are seen as relations constructed from fundamentally different building blocks, for instance, law and contract rather than nature and substance (ibid.; Schneider 1968; cf. Viveiros de Castro 2009: 258–259).1 Cousin marriage often confounds the logic of this oppositional framework, an inconvenient fact that compromises the central distinction in kinship theory between consanguinity and affinity. Indeed, it may be the pathways of affinal relations—rather than the boundaries of an exogamous unit—that are marked by similarity of substance, such as blood (McKinnon 1991: 107–133; Wagner 1967).
Starting from an ethnographic situation in which the field of marriage included cousins whose very similarity or sameness was precisely what was valued, this article examines the historical debate through which spousal similarity came to be stigmatized as dangerous and degenerative, while spousal difference came to be seen as essential to both health and heredity. In focusing on this historical shift, I therefore consider the genesis of a particular kind of marital “difference at the heart of relational belonging” and, as we will see, the “anxieties about (in)appropriate difference and similarity” (Goldfarb and Schuster, this issue). These anxieties articulated the differential valuation of class- and race-based hierarchies and equalities—inclusions and exclusions—that were as central to shifting ideas about kinship and marriage as they were to ideas about nations and national belonging.
The material I bring to bear on this matter concerns the radical shift in the valuation of cousin marriage in the United States over the course of the last half of the nineteenth century. In eighteenth- and nineteenth-century America, not only were cousins and cousin marriage the social and emotional pivot of extended family relations, but cousin marriage was also a key institution in the consolidation of the political and economic capital that formed the foundation of the emerging democratic and capitalist order in the US (McKinnon 2013). Beginning before the Civil War and intensifying after it through the turn of the century, first-cousin marriage came to be stigmatized. By the first decade of the twentieth century, it had been prohibited in 16 states (Ottenheimer 1996). It is currently prohibited in 25 states, allowed under restricted circumstances in 6 states, and legal in 19 states and the District of Columbia (NCSL 2015).
This shift, in Lévi-Strauss’s (1969) terms, from the elementary to the complex structures required the crafting of a new logic of sameness and difference. This new logic revalued sameness of being, or of ‘temperament’—which had previously been a positive motivation for cousin (or ‘in-and-in’) marriage—as a source of disease and degeneracy deemed to be characteristic not only of European royalty and their American avatars, but also of those isolated and impoverished populations left behind in the wake of the new industrial and social transformations in the US. It simultaneously valorized difference, mixing, and ‘out’ marriage as a requirement for the vitality, progress, and equality of the masses in a progressive, egalitarian, democratic social order. Yet the positive valuation of the vitality of marital ‘difference’ quickly became entangled in controversies and contradictions relating to American ideas about race when it became clear that the differences within—but not between—races were ‘vital’ to the national values of progress, equality, and democracy.
Several scholars have written works that address both historical and contemporary debates about cousin marriage. In Forbidden Relatives: The American Myth of Cousin Marriage, Martin Ottenheimer (1996) outlines the history of the prohibition of cousin marriage (and the concurrent efforts to legalize marriage between affinal relatives) in the US and goes on to debunk the myth of the genetic basis for the prohibition of cousin marriage. Adam Kuper’s (2009) book Incest and Influence: The Private Life of Bourgeois England documents the prevalence and social importance of cousin marriage in England and argues that its eventual decline in late-nineteenth- and early-twentieth-century England was primarily due to changing fertility and demographic patterns as well as the institution of new legal and economic structures. As Hall (1978) also argues, these new structures both accommodated and separated corporate capital and family inheritance and thereby rendered cousin marriage no longer the most effective means of capital accumulation and expansion. In her book Negotiating Risk: British Pakistani Experiences of Genetics, Alison Shaw (2009) explores the contemporary debate about the prevalence and health consequences of cousin marriage among South Asian immigrants in Britain.2 However, none of these works considers the cultural logic of temperaments—and the differential consequences of their mixing—that actually shaped the nineteenth-century debate about cousin marriage in the US and England. Nor do they show how the argument against cousin marriage came to express larger cultural values of equality, individualism, democracy, and national belonging—and their racial limitations.
Temperaments and Nineteenth-Century Theories of Disease and Heredity
Because the cousin marriage debate was articulated primarily in terms of disease and heredity, it is important to realize that it largely took place before the rediscovery of Mendelian genetics, before the discovery of germ-specific causes of diseases, and before the determination of the impact of environmental factors on health and disease (e.g., from sewage and industrial toxins in drinking water). Thus, the distinction between infectious, genetic, and environmentally induced diseases was virtually non-existent. As a consequence, a host of infectious and environmentally induced diseases—and their consequences, such as blindness, deafness, mental retardation, and various physical disabilities—was often on the list of characteristics thought to be the hereditary effects of consanguineal marriages (Waller 2002).
Rather than genetics, it was the reigning theory of temperaments and their relative equilibrium that informed the debate about the health and hereditary consequences of cousin marriage through the nineteenth century in the US. A physician in Louisville, Kentucky, whose articles were highly influential in establishing the argument against cousin marriage, Samuel Merrifield Bemiss (1857: 374) observes: “Nature seems to have designed that the conditions and tendencies of human organisms should be kept very nearly in a state of equilibrium.” That this equilibrium was conceived in terms of a theory of temperaments or humors is evident in the way a physician in Lowell, Massachusetts, Nathan Allen (1869: 268), formulates his “law of Nature.” According to Allen (ibid.: 269; original emphasis):
[This law] is based upon a perfect development of all the organs in the human body, so that there shall be a perfect harmony in the performance of their respective functions. In order to explain and illustrate the theory, we will divide the organs of the body into four distinct compartments called temperaments. The first division, including the brain, the spinal column, and nerves of motion and sensation, is called the Nervous Temperament; second, the heart, the lungs, and all the blood-vessels in the system, called the Sanguine Temperament; third, the organs in the abdomen, the stomach, bowels, liver, and absorbents, called the Bilious or Lymphatic Temperament; and fourth, the muscles, bones, ligaments, constituting the motive power of the system, called the Muscular Temperament.
Although the categorization of temperaments differs among commentators, the important point is that when all these temperaments are in harmonious balance and equilibrium, the result is health, well-being, and fertility. When they are out of balance, ill health, disease, and infertility result. As Bemiss (1857: 374) puts it: “This equipoise, necessary to a healthy condition of man … may be readily disarranged by giving undue predominance to any particular constitutional phase. The slighter deviations from the normal mean would constitute individual or family peculiarities; while more marked perversions become morbid manifestations, and infirmity results.”
However, this theory of temperaments not only accounted for the constitution of individuals, but also provided the core ideas for a theory of heredity, since it was assumed that temperamental imbalances and their resultant diseases would be passed on from parent to child. As Allen (1869: 289) expresses it: “[T]he more the parents were affected with scrofulous and other diseases, the more detrimental were the effects upon the offspring.” And, conversely, “the opposite doctrine is no less true, that where the organization of parents is good, the children generally will not suffer in their physical and mental qualities” (ibid.).
The position against cousin marriage was built upon the assumption that because cousins would tend to share the same organization of temperaments, cousin marriage would exaggerate the family peculiarities to morbid effect (Allen 1869: 281–282). As Bemiss (1858: 325) notes: “It will be perceived that parental infirmities are entailed with great certainty upon the offspring, and this, in the opinion of the reporter, constitutes the strongest argument against the intermarriage of relatives; the fact that family peculiarities, tendencies, and infirmities, either of mind or body, which may be so slight on the part of parents as to remain latent, become so exaggerated by this ‘intensifying’ of the same blood, that they are in the child prominent and ruinous defects.” Indeed, the dominant assumption among those arguing against cousin marriage was that because cousins are alike and are likely to have a similar configuration of temperaments, their marriage would inevitably intensify peculiarities into ‘ruinous defects’ and result in degeneration. The logical conclusion, then, was that it was best to promote marriage between non-kin, who are more likely than cousins to be constitutionally opposed or balanced in temperament. As Rev. Charles Brooks (1856: 237) asserts: “In examining the children of first-cousins, the temperaments of the parents must be specially considered; for it is thought that, where the temperaments are alike, the consequences are sure to be peculiarly disastrous; but where they are directly opposite, such consequences will not so appear.” Edward Crossman (1861: 402) notes that, in the latter case, an “exaggerated characteristic in one parent is neutralized by the antagonistic disposition of the other; and thus the equilibrium of the human race is maintained.”
Those writing against cousin marriage marshaled a range of evidence—both anecdotal and statistical—to paint a vivid portrait of what happens when the exaggerated characteristics in one parent are not neutralized by the antagonistic disposition of the other. The children of first cousins, Brooks (1856: 238) suggests, “lack that entire and symmetrical unfolding or equilibrium of the physical, intellectual, and moral powers which constitute a whole man.” Various accounts suggested that such children were monstrous in their lack of wholeness or in their excess. They would have too few eyes, too many toes, or too much hair, or they would be crippled, bent, deaf, or blind; foolish, feeble, or feeble-minded; queer, topsy-turvy, or just plain strange. These accounts were also rife with what appear to us now as clearly infectious diseases or symptoms thereof, including a host of terms relating to tuberculosis (e.g., scrofula, consumption, phthisis), whooping cough, cholera, typhoid fever, scarlet fever, pneumonia, croup, measles, fever, brain fever, convulsions, diarrhea, and dysentery, as well as other conditions such as anemia, marasmus (severe protein-energy malnutrition), hydrocephalus, apoplexy, epilepsy, cyanosis, erysipelas, dyspepsia, puerperal fever, and so forth (Bemiss 1858). All of these diseases and physical and mental maladies were attributed—in the case of the offspring of cousin marriages—to the intensifying effects of the marriage of ‘like and like’.
Those writing in support of cousin marriage argued that the fact of blood relationship must be distinguished from the consequences of the quality of temperament and the relative health of the prospective spouses. A New York physician, Robert Newman (1869: 112; see also Gardner 1861: 291), plots out the reasoning with regard to the hereditary logic of scrofulous and other degeneracies:
Therefore, we come to the conclusion, that it is not an essential result of marriage of consanguinity, that there should be scrofulous or other degeneracy … if then … two cousins of similar scrofulous predisposition marry each other, it is certain the offspring of these cousins will be more scrofulous than their parents; but it is not so by the law of consanguinity. For suppose two persons scrofulously predisposed, of the most distant and diverse race, marry, the result will be just the same without the slightest consanguinity. It is due to the predisposition and not to the blood … If two cousins are healthy and see fit to marry, there is as much reason to believe that their children would be healthy, as if they were not connected by cousinship or consanguinity at all. If their temperaments be opposite, it will be as favorable a conjunction as if they were not connected.
Thus, unlike the opponents of cousin marriage, who tended to conflate the difference between consanguinity itself and the temperamental similarities and other causes deemed to result in disease and degeneracy, it was precisely this distinction that the supporters of cousin marriage sought to clarify.
The principle of “like begetting like,” is never denied, but the various modifications arising from outside conditions—the unpredictable and startling influences upon the mother, during the period of gestation; the deteriorating habits and health of parents; the effect of the combination of similar or dissimilar temperaments; the depressing influences upon progeny of monetary or political convulsions; the affinital laws of organization, causing unity or love, disunity or hate, between parents, affecting, in an entirely unknown manner, progeny,—assuredly leave the question of the results of consanguineous marriages, although strictly an undetermined one, yet relieved of much of the evil with which it has been hitherto charged.
The debate about the positive or negative effects of the intensification of characteristics through ‘in-and-in’ marriage often relied upon analogies with plant and, especially, livestock breeding, from which both sides drew to make their points. Those supporting cousin marriage argued that, in moderation, the intensification derived from breeding ‘like and like’ actually resulted in a beneficial enhancement of traits, while those opposed raised the specter of the monstrous and unnatural consequences entailed by such intensification.
Even as he argues against cousin marriage, Arthur Mitchell, the deputy commissioner in lunacy for Scotland, nevertheless notes the positive effects of a “slight intensification” of like qualities. Mitchell (1866: 411–412) reasons: “There is a beatissimum medium in this matter as in all others. In point of fact, it is often to a slight intensification in the offspring of certain qualities of body or mind, possessed equally by both parents, that we owe those salient physical or mental characteristics which impart a power of achieving great things.” More specifically, the point is made that livestock breeders do indeed breed to enhance special qualities, such as milk in cows or speed in racehorses. Such practices were called upon to support cousin marriage by arguing that inbreeding enhances qualities instead of resulting in degeneration of the species. New York physician John Bell (1859: 481–483) takes up the issue in relation to the inbreeding of various species, both domestic and wild. With regard to horse breeding, especially those known as Morgan horses, Bell notes (ibid.: 482):
Breeding from kindred has been so common among them, that some of them still have three fourths or more of the blood of the original Morgan horse, and this although there have been as many as half a dozen generations intervening. Yet far from there being anything like degeneration apparent, these animals are universally celebrated for vigor of constitution, endurance and long life. The same course has been pursued in regard to the English hunting and racing horses; the result has been, that the descendants surpass their ancestors in all those qualities which indicate a high degree of perfection of physical organization. There is probably no country where this system has been so long pursued as in England; and there is no country which can compare with it in its horses.
Bell (1859: 481–482) generalizes that, among stockbreeders “with animals possessing desirable qualities, it is the universal custom to breed in and in, in order to preserve or strengthen these peculiarities. And this is done without any fear of deterioration in other respects” (see also Adam 1865: 723–730; Child 1862: 463–466; Gardner 1861; Newman 1869: 110–111). Oxford physician Gilbert W. Child (1862) sums up the consequences of a close examination of the analogy between animal inbreeding and human consanguineous marriage. He asserts that “close breeding is not, per se, contrary to any ‘law of nature’” and has deleterious consequences only if the parents themselves are already diseased, although he argues that “where very close and continued through many generations,” it “has a tendency to diminish fertility, and seems to do so by lessening the generative power of the male sex” (ibid.: 465). In the end, Child casts out the relevance of the analogy between animal and human inbreeding altogether for two reasons: “(a) That the risk of ill consequences in the former, as compared with the latter, is immensely lessened by the power we possess of selecting healthy stock to breed from; but (b) The degree of in-and-in breeding frequently practised in the case of animals, is so much closer than among mankind as to destroy all analogy between the two cases. No breeder of cattle would speak of the offspring of a cow—say with her sire’s brother—as closely bred at all” (ibid.: 466).
By contrast, those who see cousin marriage as an ‘evil’ resulting in the degeneration of the species use the livestock analogy to other ends. Arthur Mitchell—who, as noted above, had indicated that, in moderation, some inbreeding may produce beneficial enhancements—nevertheless comments on the artificiality and commodification involved in such livestock inbreeding. Mitchell (1866: 451) contends that “in these cases where in-and-in breeding has been practiced with so-called good results, the issue is nothing but the development of a saleable defect, which, from the animal’s point of view, must be regarded as wholly unnatural and artificial, and not calculated to promote its wellbeing, enjoyment, or natural usefulness … By in-and-in breeding we can certainly establish an artificial type, and fix a peculiarity which is unnatural, and whose only value is its profitable convertibility into gold.” He goes on to suggest that such pointed enhancement of particular qualities in humans would be monstrous: “Till the excellencies of man are estimated in pounds or inches; till the aim be a perfect artificial and not a perfect natural man; till we want legs at the expense of arms … or brain at the expense of muscle … till the perfect man be something else than a well-balanced development of all his components, bodily and mental,—we can scarcely apply the experience of breeders of stock in human physiology” (ibid.: 451–452).
The vision evoked by the opponents of cousin marriage is one of a democratic dystopia, where individuals are bred to caste positions, where individual choice yields to biological determinism, where the equality of the republican mass yields to the hierarchical disparities of breeding and pedigree, and where the very equilibrium required for health, well-being, and progress is bent away toward commercial ends.
But are the same results desirable in the reproduction of the human race? Is it not directly the contrary? Is not that man the best citizen, whose mental and bodily powers are most evenly balanced? Would the idea of maintaining through successive generations distinct breeds of statesmen, physicians, clergymen, soldiers, prize-fighters, and jockeys, be agreeable to our notions of civilization? No! what we desire is to maintain the members of the human family as far as possible in equilibrium; to advance in the mass; to progress altogether; but to check the development of individuals of exaggerated characteristics either of mind or of body, and to banish from amongst us the seeds of damage and decay.
‘Outbreeding’ and a Narrative of Progressive Evolution
If we continue to follow the imaginings about cousin marriage beyond individual heredity, it is possible to discern how Americans, in particular, conceptualized the larger social consequences of this form of social alliance. Animating Americans’ shifting valuation of kin marriages is a vision of evolutionary progress in which Americans occupy the most advanced state. This evolutionary trajectory came to be signified in terms of contrasting forms of marriage (McKinnon 2013; McKinnon and Cannell 2013a). At the lower, barbarous, and backward end were marriages that occurred in isolated places outside the currents of modern life, that turned in-and-in on themselves, and/or that were aristocratic and hierarchical in intent and privileged wealth and the conservation of inheritance above all else. At the upper, civilized, and progressive end were marriages that displayed a vitality only possible at the crossroads of civilizations, that turned outward toward others, and/or that were egalitarian and republican in intent and did not privilege inheritance of wealth over health.
Several commentators point to the high isolated valleys of the Alps as places where the deleterious effects of in-and-in breeding could, they argue, be easily observed. Allen (1869: 248) quotes a contributor to the American Journal of Insanity, who describes the valleys in the Canton of Berne where the “‘children of two brothers, of a brother and of a sister, marry as a matter of expediency, and thus preserve the inheritance intact; consequently the new family is founded in physical conditions than which nothing could be more injurious. It is in the midst of these isolated populations that we find in all its hideousness the degradation of the species, the corruption of the race. There reign cretinism, idiocy, and congenital deafness to such a degree, that the demonstration of the fact I have advanced blazes forth in all its brilliancy’” (see also Bemiss 1857: 376). This picture of degeneracy is often made an explicit counter-image to that of evolutionary progress. Allen (1869: 247) argues that in isolated and remote places where there is kin marriage and “little change in society from immigration,” the effects of the intermarriage of relatives over several generations “are marked by a loss of mental power and strength, of boldness and energy of character, with an increase of scrofulous and consumptive complaints, of defects in one or more of the senses, and not unfrequently of deformities of the body. With such a people there is not only little real improvement or progress in securing the most important objects of life, but, after remaining a while in a kind of stationary state, they gradually decline both in numbers and character.” In this, one gets a clear picture of the countervailing forces that work against the exceptional progress that otherwise is understood to define the American project. Here—outside the currents of the forward-moving mainstream—are isolated, slowly degenerating populations that are doomed, eventually, to disappear.
The other isolated and inbred population that is the target of American scorn is that of European royalty and aristocracy and their American imitators. The assumption is that concerns of wealth and rank have driven European monarchs and aristocrats and American families of wealth to marry in-and-in, repeatedly and recklessly defying what the authors see as the obvious consequences. For example, F. E. H. Steger of Maysville, Alabama, expresses his complete contempt for the Spanish monarchy in an edition of the Nashville Journal of Medicine and Surgery. The Spanish monarchs, Steger (1855: 191) contends, “from the time of Charles 5th, selected wives, often near relatives, from considerations of mere personal aggrandizement, being of royal, Spanish blood … and the consequence has been that the race is, as it ought to be, nearly extinct, exhibiting to the world a beautiful specimen of a queen in the person of the present lecherous fugitive!” Commenting on the kin marriages of the European nobility, a Kentucky physician, Charles Caldwell (1834: 31), notes that one of the causes of degeneracy is a “long perseverance in family alliances.” He goes on to state: “Witness the present royal families of Europe, that, from sceptred pride, and state policy, have long intermarried with each other. They can now scarcely muster heirs, in the direct line, to occupy their thrones—and such heirs, that, the whole of them united, would not form a well-gifted man! … Of the nobility of Portugal, I might observe the same. They were once the pride of Europe. But, by intermarriages, continued for centuries, they are now a most degenerate race” (ibid.: 31–32). Clearly, the monarchical and aristocratic orders of Europe, when bred in-and-in, are doomed to extinction in the face of the superior vigor of the outbred republics. And, within the republics themselves, those families with aristocratic pretentions come under the same criticism. Thus, Brooks (1856: 240) quotes an anecdote about the inbred Virginia aristocracy: “‘A certain family of wealth and respectability have intermarried for many generations, until there cannot be found in three or four of them a sound man or woman. One has sore eyes, another scrofula, a third is idiotic, a fourth blind, a fifth bandy-legged, a sixth with a head about as large as a turnip, with not one out of the number exempt from physical or mental defects. Yet they persevere in intermarrying, although these monuments are constantly before them.’” For these authors, it goes without saying that such aristocratic inbreeding, which places wealth and status above all else, is doomed to extinction and has no place in the new republican order.
Indeed, commentators are explicit about the relationship between ‘out-breeding’ and mixing of populations, on the one hand, and progress and the evolution of society, on the other. Steger (1855), for example, contrasts the degeneracy of in-married European monarchs with the vitality of the Turkish monarchs. The latter “from the time of Mahomet the Great brought their wives from the mountains of Circassia, inhabited by the boldest, most independent, beautifully formed and intelligent race in Asia, and the consequence was that the great deeds of the father were eclipsed by the superior achievements of the son” (ibid.: 191).
Bemiss (1857: 377) states the principle in terms of periodic migrations and the “ingrafting of nations.” He quotes Benton, who argues that “‘it hath been ordered by God’s especial providence, that in all ages there should be (as usually there is), once in 600 years, a transmigration of nations, to amend and purify their blood, as we alter seed upon our land; and that there should be, as it were, an inundation of those northern Goths and Vandals which overran, as a deluge, most parts of Europe, to alter, for our good, our complexions, which were much defaced with hereditary infirmities, which, by our lust and intemperance, we had contracted’” (ibid.: 375). More generally, Bemiss asserts that “[h]istory will … sustain the opinion that the most vigorous people have sprung from the ingrafting of nations differing in constitution and temperament from each other. I believe, with an observing writer, that the extraordinary activity and energy of the American people are due to the composite nature of their blood” (ibid.: 377).
Brooks (1856) provides perhaps the most lyrical nationalist expression of the genuine good that he perceives to be derived from the mixing of populations—at least, when limited to the ‘Caucasian’ race. He exhorts his readers to ponder the following (ibid.: 246):
Will not our country furnish the most wonderful example of the effects of intermarriages with different castes of the Caucasian race? When the people of these United States become a mixture of English, Scotch, Irish, Germans, and French, will they exhibit a strength of body and an intelligence of mind, a true inborn energy and moral power, which do not equally signalize either of the nations from whom they sprang? Under the fostering care of a truly republican and Christian government, will they advance in science, arts, agriculture, commerce, and manufactures, and all the blessings of a religious civilization and political equality, as no one of their parent nations has? Let us hope that it is the appointed destiny of our free and prosperous land, to exhibit a higher development of human attributes than has yet blessed or astonished mankind.
This sense of the vitality of outbreeding and its effects on culture is echoed in the work of Lewis Henry Morgan, a mid-nineteenth-century lawyer who lived in Rochester, New York. Perhaps the first anthropologist in the United States, and certainly the first to undertake a systematic comparative study of the structures of kinship and marriage around the world, Morgan (1871) published a Smithsonian volume entitled Systems of Consanguinity and Affinity of the Human Family. But Morgan’s contributions did not end with the description of the systems of kinship terminologies found around the world. Taking two further steps, he presumed that he could read forms of family and marriage from these terminologies, and, in his subsequent volume, Ancient Society, Morgan ( 1974) ranked them in an evolutionary progression that moved through the stages of savagery and barbarism to end, at last, with the state of civilization. Although he married his own first cousin (his mother’s brother’s daughter), Morgan does not specifically treat the topic of cousin marriage per se. Rather, he makes the more general claim that people gradually recognized the ‘evils’ of close marriage—first that between brothers and sisters, then that between collaterals (or cousins). The sequence of prohibitions also involved, he surmises, the gradual recognition of the “beneficial influence” (ibid.: 509) that was the consequence of excluding marriage between people who were closely related. Indeed, Morgan suggests that the impact of the shift from kin marriage to marriage between non-kin on the course of evolution is immense: “The influence of the new practice, which brought unrelated persons into the marriage relation, must have given a remarkable impulse to society. It tended to create a more vigorous stock physically and mentally. There is a gain by accretion in the coalescence of diverse stocks which has exercised great influence upon human development” (ibid.: 468). Morgan thus defines the evolutionary movement from savagery to civilization by the gradual increase in the distance between marriageable kin to the ultimate watershed formed by the recognition of the benefits of marrying non-kin, and he thereby ties the prohibition of cousin marriage to a larger narrative of the progressive movement toward civilization and modernity.
This picture of the vitality of outbreeding—and its necessary connection to republican virtues and the evolution of civilization—had its limits, however. Those who would insist on the negative consequences of the in-and-in marriage of cousins and the positive consequences of mixing and ‘out-marriage’ find themselves trapped by a positive exceptionalism, on one side, and what they see as a negative exceptionalism, on the other side.
While these commentators are, on the whole, men of science, they are simultaneously men of the Bible, and they are quite aware that the patriarchs of the Bible married cousins and even nearer relatives (e.g., Adam 1865; Allen 1869; Bemiss 1857; Child 1862). Bemiss (1857: 375), for instance, observes that “Abraham, Isaac, and Jacob, all married wives connected to them by blood-ties; and yet they were the chosen progenitors of a privileged and highly-gifted people, and nothing pertaining to their history suggests the idea of immediate degradation of progeny.” Wishing not to invoke direct divine intervention and exceptionalism as an explanation, Bemiss instead suggests that “the apparent inoperativeness of this law of degradation by in-and-in marrying, in the above instances, as well as in those of Adam’s sons and daughters, may be explained by the incomparably superior endowments of these primeval denizens of our globe. Those were the days in which man dwelt as it were in the presence of his Creator” (ibid.). If biblical patriarchs—and even the rugged pioneers of America, whom Bemiss also evokes—can be seen as a positive exception to the argument for mixing and out-marriage in antebellum America, there were limits to just how far ‘out’ one could go and retain the positive force of mixing.
In fact, both proponents and opponents of cousin marriage situated their arguments in relation to what they perceived as the negative exception of racial difference, which was informed by the controversy over the monogenesis or polygenesis of human origins that was current in nineteenth-century America (Haller 1970). Just after Bemiss (1857: 377) notes that “the most vigorous people have sprung from the ingrafting of nations differing in constitution and temperament,” he is quick to qualify the positive limits of ingrafting. He argues: “This rule, however, seems subject to some qualification; for there certainly exist strong reasons to believe that matrimonial alliances between the greatest possible contrasts to be found on our globe—the negro and Caucasian races, for instance—are not favourable to the most vigorous propagation of the species. I do not look upon mulattoes as hybrids, but think they exhibit less of vigour and vital force than are found in crosses where there is less contrast” (ibid.). In saying that he does “not look upon mulattoes as hybrids,” Bemiss signals that he does not perceive the races as different species, as the polygenesists would, but that he does see interracial unions as resulting in diminished vitality and vigor.
For Bell, the most positive unions are found at the close ‘in’ end of the spectrum. As one moves farther ‘out’ along the spectrum, one first encounters unions between different races that are less favorable to the “reproduction of perfect organisms,” then unions that are capable of producing only sterile hybrids, and finally the very impossibility of reproductive union.
We see this phenomenon most clearly in the human race, in those varieties most widely separated—viz., the white and black races. It is a fact which has been long recognized that mulattoes are neither so perfect in physical organization, so active mentally, nor so prolific, as the parents on either side. There is certainly more antipathy existing between these races than between individuals of the same race, however closely resembling each other … It would certainly be a singular anomaly if the series should stop just at this point, and we should find that a certain degree of difference was most favorable to the reproduction of perfect organisms, and as we recede from this point, in either direction, the offspring were less perfect.
Although on different sides of the cousin marriage issue, both Bemiss and Bell occupy a similar position with regard to the debate about the monogenetic or polygenetic origin of humans. Neither takes an extreme polygenetic position, which held that ‘Caucasians’ and ‘Negroes’ were distinct species whose sexual union would result in sterile hybrids. Yet they both suggest that interracial unions were clearly productive of less vigorous offspring and fertility, thereby placing such unions within the species but at a distance since they were deemed injurious to health, reproduction, and heredity. Thus, these arguments concerning the positive effects of out-marriage as well as the positive effects of in-marriage both hit a wall constructed out of the cultural and political economy of slavery and race relations in nineteenth-century America.
There is, in all of this, a complex calculus determining the relations of political, class, and racial sameness and difference. Ultimately, the marital logic of temperamental differences in late-nineteenth-century America was delimited by two taboos. First, the emerging taboo on cousin marriage spoke to anxieties about the shape of social relations within the ‘Caucasian’ race. The argument against cousin (or in-and-in) marriage raised the specter of a threat to progressive, egalitarian, democratic, and republican values. On the one hand, there were those cousin-marrying, would-be American aristocratic dynasties—such as the Southern plantation owners or the Boston Brahmins—who flew too close to the sun of European royalty. On the other hand, there were those impoverished families in the backward eddies of American society that had been left behind by the dynamism of the emerging industrial order. If cousin marriages tied individuals back into networks of kin—intensifying both temperaments and relative wealth or poverty—then the ban on cousin marriage and the promotion of out-marriage were thought to ensure a healthy equilibrium of temperaments—both individually and politically—and to establish a level political and economic playing field on which the masses could all progress together. However, a second taboo spoke to anxieties about the shape of social relations between the races and clearly articulated—in the context of the racial politics in America—the boundary along which out-marriage signified diminished vitality and degeneracy, if not the limits of the human species. On the far side of that boundary equality was not to be tolerated, humans could be commodified in slavery, and the reach of democratic ideals was hotly contested. This taboo policed the outer boundaries of difference that defined the racial, political, and economic limits of a national ‘shared kind’.
In The Curse of Souw (1967) and “Analogic Kinship” (1977), Roy Wagner inverts this set of assumptions by taking the Daribi perspective in which it is consanguinity that relates rather than defines units and alliance exchange that defines rather than relates units. Viveiros de Castro (2009: 254–260) lays out a series of four models of possible relations between consanguinity and affinity.
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