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‘Morals can not be drawn from facts but guidance may be’: the early life of W.D. Hamilton's theory of inclusive fitness†

Published online by Cambridge University Press:  04 November 2015

SARAH A. SWENSON
SARAH A. SWENSON*
Affiliation:
University of Minnesota Medical School, 420 Delaware Street SE, Minneapolis, MN 55455, USA. Email: swens825@umn.edu.
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Abstract

W.D. Hamilton's theory of inclusive fitness saw the evolution of altruism from the point of view of the gene. It was at heart a theory of limits, redefining altruistic behaviours as ultimately selfish. This theory inspired two controversial texts published almost in tandem, E.O. Wilson's Sociobiology: The New Synthesis (1975) and Richard Dawkins's The Selfish Gene (1976). When Wilson and Dawkins were attacked for their evolutionary interpretations of human societies, they claimed a distinction between reporting what is and declaring what ought to be. Can the history of sociobiological theories be so easily separated from its sociopolitical context? This paper draws upon unpublished materials from the 1960s and early 1970s and documents some of the ways in which Hamilton saw his research as contributing to contemporary concerns. It pays special attention to the 1969 Man and Beast Smithsonian Institution symposium in order to explore the extent to which Hamilton intended his theory to be merely descriptive versus prescriptive. From this, we may see that Hamilton was deeply concerned about the political chaos he perceived in the world around him, and hoped to arrive at a level of self-understanding through science that could inform a new social order.

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Research Article
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The British Journal for the History of Science , Volume 48 , Issue 4 , December 2015, pp. 543 - 563
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Copyright © British Society for the History of Science 2015 

How might Darwinian theory affect our understanding of who we are? Does it constrain the ideals to which we aspire? Over the last sixty years, a detailed investigation of Darwin's notebooks and published works has created a wide body of scholarship focusing on the theory of natural selection and the sociopolitical context in which it was written. Still, historical and scientific interpretations of Darwin's works have often left unanswered as many questions as they have found solutions. One of the persistent inquiries in Darwin scholarship concerns the moral significance of natural selection. Was Darwin's theory imbued with ethical values, as the evolution of moral creatures appears to suggest? Or did it describe an amoral process, which considered nothing beyond the differential reproduction of individuals?Footnote 1

Those who adhere to the latter view have seen W.D. Hamilton's theory of inclusive fitness (first summarized in 1963 but not widely cited until the mid-1970s) as a catalyst that reoriented biologists around the individualism they believe Darwin really intended.Footnote 2 Hamilton's surge in popularity was due, at least in part, to two major books that outlined the extent to which social behaviours and societies were constrained by evolution, and that placed a particular emphasis on new insights that could be gained through understanding the evolutionary process at the level of the gene. In Sociobiology: The New Synthesis (1975), E.O. Wilson hoped to lay the groundwork for unification between biology and the social sciences through an understanding of the ‘social behavior of early man and the adaptive features of organization in the more primitive contemporary human societies’.Footnote 3 In The Selfish Gene (1976), Richard Dawkins discussed the evolution of selfishness and altruism in a captivating and ultimately hugely successful way. Dawkins warned readers, ‘if you wish, as I do, to build a society in which individuals cooperate generously and unselfishly toward a common good, you can expect little help from biological nature … because we are born selfish’.Footnote 4 According to Dawkins, selfishness at the level of the gene caused selfishness at the level of the individual, except in ‘special circumstances’.Footnote 5

By the time Dawkins published, Wilson's tome, and particularly his inclusion of human societies, had already incited controversy. To some, ‘sociobiology’ was merely the most recent in a long line of purportedly scientific inquiries that used supposedly new findings to defend the ‘status quo as an inevitable consequence of “human nature”’.Footnote 6 Wilson was appalled at the accusation that his message was laced with political ideology. Defending himself, he cited a recent article in which he explicitly stated that the ‘analogies [of ant slavery] with human behavior are much too remote to allow us to find in them any moral or political lesson’.Footnote 7 Accordingly, he claimed that by describing behaviours that exist in nature, he had done nothing to insinuate that such behaviours were permissible, let alone commendable.

Dawkins was similarly shocked when his work was linked to conservative politics, and he later attributed a large part of the misunderstanding to the ‘way biologists use language’.Footnote 8 Although he later acknowledged that the 1973 mineworkers' strikes impelled him to write on the subject of selfishness, he has maintained his relative disinterest in humans and distanced himself from the egoism some seemed to read in the book: selfish genes did not create selfish humans, and even if they did, he would not advocate selfishness in any normative sense.Footnote 9

Both Wilson's conception of ‘sociobiology’ and Dawkins's ‘selfish gene’ drew upon W.D. Hamilton's decision to view the evolution of social behaviour from a ‘gene's point of view’.Footnote 10 Hamilton's now famous theory of inclusive fitness, which he first articulated in ‘The evolution of altruistic behavior’ (1963), and which he expanded upon in ‘The genetical evolution of social behaviour. I, II’ (1964), addressed observations of apparent altruism in nature.Footnote 11 Hamilton's conception of Darwinian theory emphasized the more competitive aspects of the natural world,Footnote 12 and he faithfully believed that the theory of natural selection could explain ‘absolutely everything’,Footnote 13 including the development of behaviours that seemed to harm the actor while benefiting another organism.

In 1859, in On the Origin of Species, Darwin had identified the presence of neuter individuals within insect societies as a ‘special difficulty’ for the theory of natural selection.Footnote 14 The intricate behaviours of ants and bees had long been referred to as evidence of divine intervention, and Darwin understood that if his theory was to be counted as a true cause, it could not omit to explain such significant behaviours. It was obvious to Darwin that the characteristic traits of neuters could not be selected and passed down through generations because the organisms possessing the traits did not themselves reproduce. He nevertheless posited that the problem was surmounted ‘when it is remembered that selection may be applied to the family, as well as to the individual’.Footnote 15 The entire insect community had benefited from the presence of their non-reproducing brethren, and their kind had been favoured by natural selection.

One hundred years later, however, the questions surrounding sterile castes of social insects had fundamentally changed. How did the sterile organism itself benefit from its unwavering devotion to such an extreme form of self-sacrifice?Footnote 16 Unlike Darwin, Hamilton had not been particularly interested in social insects. He had first taken his cue from the fact that altruism often occurred among related individuals. Would seeds dispersed closely together benefit from all-out competition with their neighbours?Footnote 17 Would parents who refused to sacrifice for their children be successful?Footnote 18 The pattern emerging in Hamilton's mind concerned the likelihood that the maximum number of copies of an individual's genes survived to the next generation, whether they were directly passed to progeny or indirectly transmitted through the reproduction of organisms that shared its genes. Thus, complementing Darwin's understanding of fitness as the differential survival of one's offspring, Hamilton's theory of inclusive fitness accounted for the differential survival of all organisms that shared one's genes.

For a number of biologists, Hamilton's papers marked a turning point in the history of evolutionary thinking. Within twenty years, many would agree that altruism was little more than ‘enlightened self interest’.Footnote 19 For some, this meant that ‘romantically inspired naturalists' could no longer use altruistic behaviours in the non-human world to illustrate an ‘exemplar for human conduct’:Footnote 20 evolution had little hope to offer those with communist or socialist leanings.

The implicit or explicit connection between evolutionary theory and political ideologies in this period is especially significant in light of larger debates. Were humans capable of looking beyond their individual interests to support those of their tribe, nation or global community? As scholars, politicians and members of the public alike debated which form of social organization was the most natural, and the most likely to lead to progress, biologists of the post-war decades increasingly considered the social responsibilities they had to safeguard human freedom through a biological understanding of the world's problems.Footnote 21 Comparative studies of behaviour seemed to illuminate parallels between the social worlds of humans and those of non-human animals. Their results were thought by some to limit the feasibility of new forms of social organization. By the early 1960s, American playwright turned popular science writer Robert Ardrey claimed that the ‘parochial powers of our animal conscience’ threatened our ability to survive the ‘contemporary predicament’.Footnote 22 Ardrey's series of best-selling books explicitly rejected communism. Biological ‘truths’ concerning the ‘natural’ type of society were also articulated by more esteemed scientists. Comparing men and muskrats in 1969, for example, ecologist Frank Fraser Darling claimed that the ‘gregarious’ nature of both species could not eliminate an individual's need for ‘a hole of his own’.Footnote 23

Since Hamilton highlighted social insects in his early papers and many of his early supporters were entomologists, his contribution is often assumed to have resulted from an astute understanding of insect societies.Footnote 24 Abundant archival evidence, however, highlights a fact that Hamilton himself admitted throughout his life: it was not until after the mathematical equations supporting his theory had been worked out and his ideas were for the most part written up that he understood the relevance of the unique breeding structure of the Hymenoptera to his theory.Footnote 25 His initial observations, and the basis of his theory, drew in large part upon his reflections on human society.Footnote 26

While Hamilton's extra-scientific beliefs, including his dismissal of Marxist and Christian doctrines of sociability, certainly did not cause him to arrive at the conclusions he did, they nevertheless shaped the line his research took as well as the range of solutions at his disposal. Understanding this shaping of Hamilton's work adds to scholarship surrounding the political dimensions of the levels-of-selection debates, the sociobiology debates, and debates surrounding the evolution of altruism in particular. From their earliest days, these conflicts have often centred upon traditional depictions of scientific ‘truth’ in battle against deeply held cultural beliefs. In 1976, Dawkins convincingly framed the debates surrounding group selection in political terms. Well-meaning humanists, reacting ‘against racialism and patriotism’, had been duped by the alluring but scientifically untenable belief that traits could evolve for the ‘good of the species’.Footnote 27 Similarly, Wilson believed that those who opposed Sociobiology were ‘openly partisan’, concerned not with the scientific basis of his ideas but with a non-existent conservative agenda that they had mistakenly read into his text.Footnote 28 These frameworks have proven persistent.Footnote 29 Increasingly, however, scholars have added to these early interpretations of the conflicts surrounding the evolution of social behaviour.Footnote 30 Through their works, we are better able to understand these scientific debates within a dynamic political and social world.

Nevertheless, it is important to consider Hamilton's contribution in its own time and terms, and not, as it is easy to do, in anticipation of the controversies that were to come or the status his theory would achieve. In light of the long history in which evolutionary theory was brought to bear on discussions of humankind, I argue that the theory of inclusive fitness is better understood when we set aside assumptions that it was a natural truth ripe for discovery and instead consider its creator's larger aims. A more nuanced understanding of the relationship between Hamilton's scientific inquiry and its social and political context is especially important when we consider the extent to which biological theories of social behaviour were meant to move beyond description to prescription in the second half of the twentieth century.

To understand the connections between Hamilton's biological interests and contemporary social and political concerns, I will explore Hamilton's work in the first decade after his theory of inclusive fitness was published. Through archival materials, we can first begin to see the extent to which Hamilton felt his theory was relevant to an understanding of human society during these years. Next, we can investigate the particular ways in which Hamilton saw inclusive fitness to encompass wider meaning, with special attention given to his views on the nature of race-based conflicts. From this, we are better able to understand whether Hamilton intended inclusive fitness merely to describe the behaviours of social animals, or also to prescribe behaviours for humankind.

The relevance of inclusive fitness to human society

In 1991, Hamilton complained that ‘a lot of people misconstrue … the role of the male haploidy of hymenopteran social insects in my theorising’.Footnote 31 By his own account, he had first become interested in altruism through his interpretation of human behaviours. He intuitively sensed that altruism was prevalent throughout the natural world more generally but knew of few non-human examples. Without these, he doubted whether he would be able to prove that altruistic behaviours were biological rather than cultural phenomena. Speaking of his desire to locate non-human examples of altruism, he later declared,

Although I didn't want to rely on examples which involved man, it's always seemed to me that there are such obvious parallels between the human world and the animal world that one can quite justifiably use one's own introspection … and so I took phenomena like parental care, the existence of things like blood feuds in man … These were some of the examples obtained by introspection which … gave some guidance in suggesting that an important principle would be closeness of kinship.Footnote 32

But there is reason to believe that humans were not only a source of information for Hamilton but also the motivation for his work. In 1965, for example, Hamilton wrote to anthropologist John Pfeiffer that ‘the hope of arriving at some new understanding of human social evolution was a major incentive’ to see his research on inclusive fitness through. He was enthusiastic to hear that Pfeiffer had been thinking about taking ‘ideas of this kind into account in a book on human evolution’. Hamilton confessed that he had thus far refrained from ‘writing anything directly on this’ because ‘people seem to react rather more sharply to half-baked ideas on this subject’ than they did to ‘half-baked ideas in general’. What is more, population models were often built under assumptions of large population size and random mating, and Hamilton feared that his model might break down when applied to ‘the population systems of small and presumably rather endogamous groups that seem to be characteristic of apes and baboons –and presumably of the early hominids’. In fact, he thought ‘it may be that evolutionary arguments based on the rather vague concept “group selection” are really sounder than my paper would seem to indicate’, at least in man. Still, he thought it would be a mistake to dismiss genetic evolution in the human species as ‘either over or unimportant’.Footnote 33

In the same year, Hamilton claimed it was likely that ‘genes for anti-social behaviour’ existed within the human populations, and he believed that these were one cause of suffering in contemporary society. Indeed, he felt that natural selection might favour the evolution of antisocial behaviour in species ‘whose colonies reproduce much more diffusely, as do those of man’. Although he did not negate education as a possible partial remedy,Footnote 34 he later declared that the only means of decreasing violence from an evolutionary standpoint would be to pass legislation that would ‘encourage not merely the direct influence but also the breeding of citizens democratically considered above average in ability, kindliness, and health, while discouraging influence and breeding from opposites’.Footnote 35

Already in 1965, Hamilton opposed trends in the social sciences that emphasized learning over instinct, writing, ‘it seems doubtful to me if our seemingly blank cheque of mental development is really so blank as is sometimes assumed’.Footnote 36 Reiterating his early interest in R.A. Fisher's controversial discussion of human evolution in The Genetical Theory of Natural Selection (1930), Hamilton claimed, ‘Most of my thought in this field is inspired by that amazing book of Fisher's’.Footnote 37 He lamented that Fisher had ‘been rather too severely disregarded just because he proved wrong in his interpretation of contemporary population trends, and therefore also in certain parts of the theory he based on this interpretation’. Hamilton maintained, ‘it will have to be recognised eventually that a lot of the ideas in this section of the book are basically correct’.Footnote 38

Fisher's chapters on man were explicitly eugenic, but when Hamilton read them while he was an undergraduate student at Cambridge they reinforced rather than instigated his own eugenic concerns. As early as 1954, Hamilton identified the ‘subject of improving man's brain by selection’ as ‘my subject’,Footnote 39 and in 1956 Hamilton made explicit reference to the relevance of Britain's recently established welfare state to his concerns regarding human evolution. Writing to his sister Mary, he claimed, ‘in the increasingly world wide “welfare-state”, the intelligent man earns no more money than the fool & is unable to support more children: on the contrary, the more uneducated & stupid a person is the more children he tends to have’. He could not say with certainty whether the blame lay with the government, for ignorantly rejecting birth control measures, or with impoverished individuals and their personal shortcomings. It was nevertheless clear to him that the welfare state would increase the need for medical services in future generations, an effect that he believed was a serious cause for concern.Footnote 40

Writing in 1965, Hamilton did not encourage the abandonment of welfare provisions to prevent ‘wholesale killing by strife, famine and disease’, but he did believe that the establishment of the welfare state caused problems that would have to be addressed through policy. He feared that the necessary policies were unlikely to be put in place, ‘to judge by the outcry that greets attempts to secure even moderate changes in the law on abortion’. Hamilton's own recommendations, namely policies permitting infanticide, would, he recognized, likely be met with even greater hostility.Footnote 41

Discussions surrounding the frailty of the welfare state in 1950s Britain were entangled in concerns surrounding immigration. Conflicts that seemed to be wholly or partially influenced by tensions between racial groups had been a topic of concern in the first decade after the Second World War.Footnote 42 Domestic anxieties regarding race relations escalated after the 1948 British Nationality Act opened the country to citizens of its former territories. Politicians across the ideological spectrum considered immigration restrictions as early as 1951.Footnote 43 The implementation of these restrictions was hindered in part because it was politically difficult to distinguish ‘between white would-be immigrants from the old dominions’, who were welcome, and ‘non-white [immigrants] from the newly independent Commonwealth countries … and from British colonies’, who were suspect.Footnote 44 Lord Salisbury, for one, tied questions of immigration to the viability of the welfare state, arguing that welfare provisions lured the wrong type of immigrant to Britain and thus created what he termed a ‘coloured problem’.Footnote 45

While such discussions among politicians were not made public, anti-immigrant sentiments increased throughout Britain from the late 1950s, and during these years Hamilton himself was apprehensive about increased immigration of non-white individuals to his country.Footnote 46 Although he opposed racial segregation, Hamilton recognized that he was not immune to the ‘seeds’ of racial prejudice.Footnote 47 That he was correct in this self-diagnosis is clear from a letter he wrote to a friend while he was working as a research assistant in Aylesford in 1957, one year after a wave of ‘New Commonwealth’ immigrants had come from the West Indies.Footnote 48 When he came to share accommodation with two Jamaican immigrants, he complained, ‘my room is in a sad state, what with all this packing up & what with this invasion of black men’.Footnote 49

According to Hamilton, the ‘invasion’ had also provoked his landlady, who, he surmised, was instinctively terrified of the men. To him, this fear was no less expected or unnatural than the pervasive fear of ‘caterpillars & spiders’.Footnote 50 Hamilton himself had initially been ‘most disturbed’ by the two men, and days later he still could not ‘help finding 2 blackmen [sic] rather more overwhelming than two white’. He found their habits odd, for one, but he also saw their actions through the lens of common stereotypes, believing them to be both hypersexual and in other ways childlike. Initially, he assumed they were

rather feckless & empty-headed individuals just as negroes are so often represented. Partly it was that wild … laughter (which I now believe is namely the product of nervousness due to our lack of understanding & mutual prejudice) & partly their prompt insinuation into what I would consider my private affairs … They seem to have a rather unpleasant licence in discussing sexual matters.Footnote 51

Amidst such discomfort, he was relieved to vacate the room soon, although his inner naturalist was disappointed that he would not have the opportunity ‘to study them for longer’.Footnote 52

Hamilton's tendency to observe and characterize human groups was far-reaching. When he travelled through Ireland, for example, he wrote home to say, ‘All up that valley there is a most striking resemblance between the people; they are all short dark, swarthy, a really gaelic people I expect’.Footnote 53 Hamilton found Ireland to be especially interesting from a biological perspective because he thought it ‘must be one of the few European countries where racial types are at least preserving themselves if not evolving. There is absolutely no immigration’. Hamilton discounted the apparently common belief that ‘the Irish [were] dying out’. This was, he averred, ‘only apparent: it's just that since the famine the state of the country has been such as to encourage all the more fertile members to emigrate’. What is more, it was clear to Hamilton who was to blame for the country's misfortunes. When confronted by people who ‘look[ed] enviously at the progressive industrial North’ and complained that it was subsidized, he could not help but feel ‘that is their own fault’ since they had withdrawn from the Commonwealth.Footnote 54

What comes out of these and other conversations between Hamilton, his family and his friends is the idea that poverty and hard luck had an internal cause. For Hamilton, the correlations between race and inherited characters were not always negative. For example, he told his parents that the ‘remarkable racial talent of the Hungarian jews [sic]’ manifested itself in some of his professors.Footnote 55

The topic of race was also a concern for biologists who urged that their discipline represented the objective face of the future.Footnote 56 By 1963, Julian Huxley had already called for a replacement of ‘old frameworks of thought’ with a new scientific morality.Footnote 57 As Marianne Sommer has highlighted, Huxley disagreed with his famous grandfather, Thomas Henry Huxley, who had argued that evolution offered no moral lessons for humankind.Footnote 58 As a pathway towards peace and progress, Julian Huxley's scientific morality rejected competition between populations, which he believed formed the basis of Nazi ethics.Footnote 59

Elsewhere, however, biology was being used to explain the prevalence of conflicts between groups, and especially between races. In fact, an Institute of Biology symposium in 1963, which Huxley attended, demonstrated that biologists concerned with the nature of aggression and its counterpart, social cohesion, were turning their eyes towards civil rights issues in the United States. They were interested in the extent to which racial conflicts were relevant to conceptions of genetic dissimilarity. W.M.S. Russell, James Fisher and L. Harrison Matthews, for example, discussed whether human races could be effectively compared to ‘geographical races of one animal species, when they meet again after the long period of genetic divergence necessary for them to become separate species’. Russell had claimed that human conflicts were ‘only cultural’, but Fisher and Matthews disagreed. They believed that such conflict could be a biological response to genetic divergence.Footnote 60

This discussion caught Hamilton's attention, and he annotated the relevant passages in his copy of the volume produced from the symposium. Considering Russell's claim that prioritized cultural divergence over genetic divergence as a cause of intergroup conflict, Hamilton scribbled, ‘I don't see why’. In the responses of Fisher and Matthews, on the other hand, Hamilton's own ideas were reaffirmed.Footnote 61 For him, increasing genetic differences were at the root of decreasing social sympathies, and they contributed to the prevalence of racial conflict.

The anxieties associated with immigration in this period can also be seen in a note Hamilton made after reading a contemporary Guardian article. From the article, he quoted, ‘The time is very short to prevent a racial war which is fast becoming an ugly inevitability in the world.’ Furthermore, he copied the article's claim that the ‘white man … will suffer most’.Footnote 62 Thus we see that Hamilton was certainly aware of the alarmist rhetoric surrounding the increased heterogeneity of British society in the post-war decades, and he would explicitly state that ‘nepotism, tribalism and racialism are natural phenomena with deep roots in the animal ancestry of man’. This comment, made in Hamilton's abstract for the 1969 Man and Beast symposium, was not the first time he considered inclusive fitness in relation to man.Footnote 63 However, it was perhaps the most public attempt he had made up to that point to explain his theory's relevance. Furthermore, the publicity surrounding the event demonstrates the potency of Hamilton's theory when considered in connection with pervasive assumptions about race-based conflicts in this period.

According to Hamilton, ‘racialism’ resulted from what he referred to as his ‘racialistic principle’. It stated that increased cohesion within groups of related individuals would correlate with increased hostility towards outsiders, and it was something he had developed even before he had read Konrad Lorenz's On Aggression, first published in English in 1966. Lorenz's chapter on rats merely reinforced Hamilton's intuition by highlighting the fact that despite ‘very harmonious intragroup relations’, the ‘intense intergroup aggressiveness’ of rat colonies meant that an outsider placed within an existing group was almost always brutally killed. In fact, it seemed to Hamilton that rats were possibly the ‘most communistic of mammals’.Footnote 64 After reading On Aggression, however, Hamilton was disappointed that Lorenz only spoke of humans ‘in veiled terms’.Footnote 65

Still, a more explicit discussion of the relevance of Lorenz's non-human examples to man was not necessary for others to draw meaning from the book. Poet W.H. Auden, for example, recommended On Aggression as a ‘key book for the understanding not only of the “dumb” beasts, but also of the loquacious human species’.Footnote 66 Lorenz's idea that civilization was provoking man's ‘innate aggression’ was referred to in a 1967 Guardian article on road violence.Footnote 67 In 1968, Lorenz's book was celebrated as an ‘instant classic study of animal (and human) behaviour’, and by 1969 readers were even extending his conclusions to speak to the situation in Northern Ireland.Footnote 68

The human world appeared as chaotic to Hamilton as it did to others who read Lorenz, and as he prepared his paper for the 1969 symposium inspired by Lorenz's book, he seems to have vowed to be bolder. In examining the organization of the symposium in greater detail, however, we might assess to whom and for what purposes biological theories of social behaviour appeared most relevant by the end of this turbulent decade.

Bringing the meaning of inclusive fitness to the public

Veiled or not, the sociopolitical ramifications of Lorenz's discussion for human society were clear. In light of Lorenz's text, the Smithsonian Institution invited biologists to discuss the science of social behaviour in May 1969. Although Lorenz's book was the initial impetus behind the event, the organizers recognized that it was not unique in either its themes or its concerns.Footnote 69 The organization of the symposium began in 1967, and the majority of the initial work fell to Matthew Huxley, an epidemiologist who was the nephew of Julian Huxley. When Matthew Huxley left the Smithsonian for the National Institutes of Mental Health, the task was passed to the secretary of the Smithsonian, S. Dillon Ripley.Footnote 70 A biologist himself, Ripley was excited to note that after Lorenz's book, further scholarship on the subject was seemingly flying out of the presses. ‘Now Lorenz has been followed by Robert Ardrey, Ardrey by Desmond Morris, and now Anthony Storr's Human Aggression. The books continue to pour out!’ he wrote.Footnote 71 He hoped the event would engage the general public as well as bring science to the ‘Washington “Establishment”’.Footnote 72 Beyond politicians, he intended to create an audience of writers, journalists and educators, as well as philanthropists and ‘others with an interest in promoting the application of the results of scientific inquiry to human needs’.Footnote 73 Lorenz was contacted as early as 1967, and although he was enthusiastic about the event, illness prevented him from attending.Footnote 74

With the above audience in mind, the organizers hoped to recover the ‘meaningful insights’ of biologists that were at risk of being ‘lost in a shrill debate between partisans of exaggerated, ideologically influenced stereotypes of human nature’.Footnote 75 The main question the organizers hoped to address was ‘what can man learn from the scientific study of the behavior of animals that might help him to deal with himself’.Footnote 76 Moreover, the organizers hoped that the insights from comparative studies would move beyond inquiry to application. They wondered, ‘what new possibilities for controlling human behavior’ might open up and ‘how [they could] guarantee their exercise [would] be by democratic means’.Footnote 77 Their concern was not only for domestic policy but also for international relations, and, they proposed, ‘the behavior of nations in the postwar period should be examined for clues to patterns of self-restraint as a basis for survival’.Footnote 78 The organizers were in fact so convinced of the importance of their event that they attempted to secure Prince Philip as the symposium's honorary chairman, but he either could not, or did not wish to, assume this role.Footnote 79 For speakers, they settled upon Marvin Bressler, John H. Crook, Irven DeVore, Robin Fox, Louis J. Halle, Hamilton, Julian Jaynes, Hans Kummer, Susanne K. Langer, Glen McBride, Margaret Mead, Detlev Ploog, E.O. Wilson, and Robert B. Zajonc.

In his contribution, Hamilton claimed that the evolution of altruistic and selfish characters, and indeed their capacity to evolve, depended on the breeding structure of a particular population. Whatever the breeding structure, however, total social harmony across populations was impossible. A limited degree of altruism could be promoted in stable groups – that is to say, in those with low migration rates – but increasing harmony within a group would likely correlate with increasing hostility towards individuals outside the group.Footnote 80

It was for this reason that Hamilton saw the problems plaguing human societies, including nepotism, tribalism and racialism, to be natural rather than social, economic or cultural. What is more, he noted that the cruellest wars were often those that involved racial and religious differences. As evidence for this claim, he cited among his sources social anthropologists, namely the avowed critic of Margaret Mead, Derek Freeman.Footnote 81 Hamilton also claimed to have drawn upon historical literature when constructing his ideas. With regard to more biological sources, he referred to the fossil record and Robert Ardrey's killer-ape interpretation of it, to studies in primate behaviour, and to theoretical considerations of the evolution of social behaviour.Footnote 82 These considerations relied heavily on introspection. He later made this explicit when he stated that the paper reflected beliefs that ‘for better or worse … originate[d] out of … an honest analysis of [his] own psyche’ and its tendency to produce ‘violent and sadistic ideas’.Footnote 83

Hamilton's naturalization of tribalism is particularly noteworthy, as he claimed that warfare was the extension of tribalistic tendencies by intelligent animals. For this reason, he believed that war was a ‘natural development from the evolutionary trends taking place in the hominid stock’.Footnote 84 As further proof, he cited similar phenomena between ant colonies, which also exhibited behaviours that resembled slavery and robbery. Since these behaviours were ‘elaborate instinctive patterns’ evolved by natural selection in ants, Hamilton found it hard to imagine that the corresponding phenomena in man were without any natural basis.Footnote 85 His conclusion, therefore, was that ‘natural human culture is inhuman’.Footnote 86

As has already been noted, the audience for Hamilton's talk included politicians. Hamilton ‘vividly’ remembered one senator's wife ‘pinning me at once with her chin and her fierce eyes as she asked me how my theory could reduce violence and crime in America’.Footnote 87 Indeed, his discussion of intergroup fighting may have appeared extremely relevant in the US where news of race riots had become commonplace. In stark contrast to the non-violent protests of earlier years, the ‘un-civil’ tactics of black radicals in the mid-1960s bewildered politicians.Footnote 88 Right-wing periodicals such as the National Review quoted Ronald Reagan as having already, albeit more casually, compared the behaviour of rioters to animals, calling them ‘mad dogs against the people’.Footnote 89 Even left-wing magazines had traced the core issue to ‘human nature itself, which can't be changed’.Footnote 90 While some believed that poor black people were being manipulated by outside agitators, antagonisms were nevertheless largely reported to be the product of racial difference.Footnote 91 Upon being arrested in Cleveland in 1968, black nationalist leader Fred Ahmed Evans was reported to have said, ‘If my rifle hadn't jammed, I'd still be killing you whites … This is only a warm-up. This is only a preliminary to what is going to happen’. His comment seemed to give some justification to white fearfulness.Footnote 92

Such pervasive fears may have contributed to the relative ease with which the Man and Beast conference organizers funded their elaborate event. Beyond an extravagant opening procession of speakers, two by two and in full academic dress, across the National Mall, the budget for the symposium was $51,415, although $65,000 had initially been calculated.Footnote 93 In seeking funds, Dillon Ripley was careful to relay to potential sponsors the idea that evolution did more than influence man's physical character. It had also, he noted, ‘innumerable continuing influences upon his psyche and … his social behavior’. It was clear to Ripley ‘that human societies … must play roles for which our species was cast in a shadowy and immemorial past’.Footnote 94 Biology was thus set to illuminate ‘deep secrets of human identity’, and if policymakers wanted to be effective, they would have to take note.Footnote 95

Among the major donors for the symposium were the Russell Sage Foundation ($15,000), the Commonwealth Fund ($5,000), the Alfred P. Sloan Foundation ($5,000), the Grant Foundation ($5,000), CBS ($2,500), and the Luana Foundation ($1,500).Footnote 96 Endorsing the symposium, John A. Schneider, the executive vice president of CBS, wrote,

This sounds like an extremely worthwhile and important meeting … there is indeed a growing interest in this whole area of animal behavior, and anthropology appears to be entering a new, exciting and very fruitful dimension of inquiry that will help us better understand why man is what he is – and does what he does … In this period of great social change and challenge we are … only beginning to understand the importance – even urgency – of this analysis.Footnote 97

Schneider was not alone in articulating the weight and meaning he perceived the event to have. In April 1969, Paul R. Ignatius, president of the Washington Post, wrote to Ripley to declare his $1,000 corporate sponsorship of ‘this important event’.Footnote 98 Also committing $1,000, Marshall K. Evans of the Westinghouse Electric Corporation wrote, ‘the Symposium will serve a very desirable objective’.Footnote 99 Even companies that declined sponsorship were nevertheless careful to acknowledge the event's importance.Footnote 100 Some cited budgetary pressures created by ‘the urban and racial crisis’ as the reason they could not contribute.Footnote 101 Harry F. Guggenheim, who had been identified as a potential lead donor, declined because he had decided to put his resources toward his own programme concerning ‘man's relation to man’.Footnote 102 Although this was disappointing, the organizers were unperturbed. With a symposium that touched on a number of pressing concerns, they did not doubt that adequate funding would be found.

Reports covering the event reveal a sense of optimism that insights into human problems could be gleaned from the biological study of ‘lower’ animals.Footnote 103 While not everyone agreed that worthwhile comparisons could be made between group behaviour in other animals and group behaviour in man, Arkansas senator J. William Fulbright, known for his racist views and unrelenting opposition to civil rights reform in the 1950s and 1960s, evidently saw potential in the discussion.Footnote 104 He held a mini-symposium in his hearing room on the second day of the event, during which ‘bright young scientists’ discussed ‘war, ABM [anti-ballistic missiles], education, masculinity, primates, incorrigible youth, the pill and related subjects’.Footnote 105 Reporter Herman Schaden claimed that what Fulbright and others really wished to know was, ‘How can we induce people to live together harmoniously?’Footnote 106 Unfortunately, no succinct answer was forthcoming.Footnote 107

Also interested in the relevance of the symposium to current events was Louis J. Halle, an international-affairs scholar who provided the concluding remarks.Footnote 108 Halle highlighted two key facts that give us insight into what had become an age of anxiety.Footnote 109 First was the general agreement among symposium organizers and attendees that ‘love one another’ was a hopeless mantra, a delusion of the past that had proved unsuitably idealistic throughout human history. Second was the relevance that the symposium was seen to have to recent instances of ‘racial antagonism in the United States’. Halle believed it was inevitable that the two groups would ‘continue to dislike one another’, supposedly on the basis of racial differences alone.Footnote 110

Did people take notice of the natural boundaries that Hamilton posed in considering positive social behaviours? Senator Fulbright, for one, is said to have asked at the conclusion of the event, ‘How does one go about influencing the attitudes of people to get them to look beyond their own little groups?’Footnote 111 For Hamilton, this question was likely more accurately framed to ask, can we get people to look beyond their own little groups? Human history seemed to prove again and again the reality of the ingrained animosity between populations, and it was unlikely that policymakers would do anything to change it. Thus, although the theory of inclusive fitness itself cannot be defined as a racist doctrine that served to articulate conceptions of racial superiority, it definitely spoke to contemporary issues surrounding race. In seeking to clarify why individuals had a very difficult time trusting, empathizing with, and welcoming members of another racial group, it characterized racial tensions in terms of evolved tendencies that were based on immutable degrees of relatedness.Footnote 112 Hamilton's decision to view the limited potential for racial harmony in this way, of course, pre-dates the development of his inclusive-fitness theory. It was one of the facts of nature from which he worked. For him, there existed ‘decidedly an instinctively held ranking of classes of people for whose benefit one is prepared to perform altruistic action, & it places highest one's immediate kin & lowest strangers (or foreigners or enemies)’.Footnote 113 Things got very complicated indeed when foreigners became countrymen.

Post-war evolutionary theories: descriptive or prescriptive?

When Hamilton returned to England, he did not leave Man and Beast behind. He used his Smithsonian Lecture as part of his teaching at Imperial College, and it also informed his contributions to Social Biology, a new course jointly organized between the zoology department and the Industrial Sociology Unit.Footnote 114 Moreover, in 1971, Hamilton drafted an article for New Scientist that highlighted the relevance of biological theories of social behaviour to the human world. According to him, they could help explain both ‘[why] do the workers strike?’ and why ‘a questionnaire … reveals a number of people who both think that Britain, say, is already overpopulated, and at the same time declare laissez-faire attitude to birth control regarding large families, or even a personal intention to have four five or five six children?’ As Hamilton saw it, biology asserted that hopes of natural solidarity were ‘chimerical’, and that ‘even the most ardent utopians’ could not solve the core problem, namely that ‘man is at heart an animal still’.Footnote 115

Although he did not make particular policy recommendations in 1971, Hamilton had earlier indicated that his approach to population control might give every person of marriageable age ‘rights to participate in the parenthood of two children’, which could then be passed to another individual if preferred.Footnote 116 He elsewhere referred to such ‘rationing’ of reproduction as ‘the enlightened step’ governments might take.Footnote 117 Hamilton spoke more explicitly to the role of evolutionary theory in informing policy when he wrote an article meant for the Observer magazine in 1974. In it, he claimed, ‘Morals can not [sic] be drawn from facts but guidance may be’.Footnote 118

This was not the only time Hamilton indicated his belief that the biology of social behaviour could inform human society. In an undated lecture likely from the early 1970s, Hamilton again rejected ‘the “blank sheet” view of human sociality’, adhering instead to the idea that ‘some things, some ideals, are much more easily taught than others’. He saw human nature to be ‘a sheet rather heavily [marked] with lines that seem to suggest some strong but brutal edifice’. The ‘problem of civilisation’ was ‘how to erase or adapt these lines … which seem like cracks in the very foundations on which civilisation tries to stand’. The problem was especially challenging because it was difficult to know whether such erasures would damage the ‘structural stability’ of the human gene pool.Footnote 119 Thus, despite having lived through perhaps one of the greatest periods of social transformation, Hamilton offered little encouragement for true and lasting change.

When Hamilton's ideas were explicitly applied to society and popularized from 1975, they threw Hamilton and the theory of inclusive fitness into the spotlight. From 1964 to 1973, Hamilton's papers were cited on average fewer than ten times each year. From 1974 to 1983, they were cited around sixty times per year, and the number of yearly citations has only increased since then.Footnote 120

As our earlier discussion of Wilson and Dawkins has illustrated, a major complaint of sociobiologists from 1975 was that the scientific theories they concocted should be absolved from association with political critiques; their theories, they argued, were descriptive, not prescriptive.Footnote 121 In other words, by telling what was, they claimed to be saying nothing of what should be. Such claims were clearly at odds with what Hamilton intended in devising the theory. What is more, they do little to explain the attractiveness of inclusive fitness from the mid-1970s among both popularizers and the general public.

Evolutionary biologist John Maynard Smith noticed the discrepancy between sociobiologists' declarations of disinterest and their opponents' criticisms as early as 1979. According to him, part of what made sociobiology so controversial was that scholars could not agree whether ‘evolutionary biology [can] be a source of moral values’.Footnote 122 This question is tied to conceptions of ‘the naturalistic fallacy’, a conflation of ‘is’ and ‘ought’, which, as historian Piers J. Hale has recently documented, had been a component of evolutionary theories throughout the nineteenth century and into the twentieth.Footnote 123 Most famous, and most written about, have been the prescriptive accounts of evolution associated with what was retrospectively called social Darwinism and with eugenics, each of which had both its advocates and its critics.Footnote 124 Thus Nathaniel Comfort has documented the enduring appeal of eugenics throughout the twentieth century.Footnote 125 But in England, at least, social Darwinism – the endorsement of laissez-faire economics that some commentators drew from their reading of natural selection – was seen as distinctly problematic by the 1870s, and the entire endeavour to apply evolution to humanity fell out of favour in the aftermath of the First World War.

The relationship between evolution and ethics had again become a topic of debate by the time Julian Huxley advanced the idea of evolutionary ethics. Huxley's understanding of evolution offered firm foundations for peace and progress, and Sommer has argued that the creators of the modern evolutionary synthesis reaffirmed an understanding of human evolution as somehow separate from the rest of the natural world, offering significant possibilities for self-directed improvement in the 1930s and 1940s.Footnote 126 As Mark Borrello has shown, attempts by naturalists like V.C. Wynne-Edwards to draw harmonious conclusions for mankind from their observations of the natural world were initially welcomed, especially in the 1950s and early 1960s.Footnote 127 Some, such as Irenäus Eibl-Eibesfeldt, seemed to believe that an understanding of evolved aggressive tendencies offered an opportunity for world peace: tribalistic sympathies could be consciously extended to include the human population as a whole.Footnote 128

Hamilton disagreed, but it was in this context that he published his papers. Moreover, it is against this background that they were read. By the 1990s, some scholars looked back and saw sociobiology, inspired by Hamilton, as having successfully achieved what earlier renditions of evolutionary ethics had failed to do, pulling humanity out of a ‘minor dark age’ in which the relationship between evolution and ethics had not been understood.Footnote 129 As P.A. Corning phrased it, ‘sociobiology forced its way through the previously barred doorway into the social sciences’, and in doing so, it arguably legitimized evolutionary ethics.Footnote 130 Robert Trivers even went as far as to claim that Hamilton had ushered in a second wave of social Darwinism.Footnote 131 In his eyes, this was a positive development.

Despite the almost perpetual political debate that has surrounded discussions of evolution and ethics since the publication of Darwin's On the Origin of Species in 1859, it has somehow become a well-established myth that Hamilton was primarily concerned with social insects.Footnote 132 Even when this is challenged, however, Hamilton's authority remains intact. Ullica Segerstrale's recent biography of Hamilton, for example, dispels assumptions that Hamilton was ‘a wasp or insect man’, but it does so with the goal of increasing the generalizability of Hamilton's work rather than questioning the origins of his ideas or the value that they held.Footnote 133 As her title suggests, Segerstrale sees Hamilton as ‘nature's oracle’, having worked in an epistemological one-way street from natural observations to carefully considered conclusions about man.Footnote 134

Although some scholars have taken Hamilton's interest in promoting human self-understanding through evolutionary theory seriously, current biographies of Hamilton moderate our understanding of the impact of his political beliefs on his scientific work.Footnote 135 In doing so, they impede our ability to recognize Hamilton's intention to understand behaviour in both descriptive and prescriptive terms. Segerstrale, for example, isolates Hamilton's eugenic interests in ‘his youth’.Footnote 136 Indeed, Alan Grafen has labelled Hamilton's foray into eugenics in the 1990s as – far from being connected to his scientific work – having a ‘non-scientific and even political theme’, and Grafen's was certainly not the first attempt to separate Hamilton from what had become unsavoury politics.Footnote 137 As Trivers explained to his Harvard graduate students in 1978, Hamilton's theory of kinship did not imply that racist behaviour was either good or natural.Footnote 138 Still, as the controversy surrounding sociobiology raged, Trivers suffered personally from protests surrounding the accuracy of the new science of social behaviour. He had been labelled a ‘sexist, fascist, racist pig’ and accused of helping to lay the foundations for a racist synthesis.Footnote 139

At the time, Trivers was co-teaching a course on Natural Selection and Social Theory with Hamilton, and he had professional reasons to introduce Hamilton as an objective naturalist, deeply involved with social insects and only secondarily interested in human evolution.Footnote 140 Despite teaching at one of the world's most elite institutions, Trivers's career was on rather unstable ground. He had come up for promotion in 1974 and 1977 but was unsuccessful. This, he felt, was due to the conflict Wilson and Dawkins had stirred up, although, as he said to Hamilton, ‘the President and the Dean vigorously deny the notion that the political attacks had any effect on their decision’. However, the dean had told Trivers personally that much of his work was ‘untestable’. What was worse, a reliable source had told Trivers that Harvard's president had wondered whether this whole ‘“inclusive fitness business” may disappear without trace five years from now’.Footnote 141 With regard to his failed promotion, Trivers concluded, ‘the obvious relevance of our work for the social sciences ended up counting against me’.Footnote 142 While he distanced himself from social scientists, Trivers used observations of humans to derive insights about other animals, and this meant he had much to lose if sociobiology was rendered untenable.Footnote 143 By grounding Hamilton's work in the careful study of social insects, he made it possible for his own work to appear less biased or political.

Setting Trivers's interpretation of the meaning of inclusive fitness aside, Hamilton's own position on the nature of race-based conflict, and his ‘racialistic’ theory in particular, appear to be much more complicated and inextricably linked to his biological reasoning. Beyond issues of race, Hamilton also indicated that biology ‘can help to show whether a given course of action will succeed in procuring a chosen good or not’.Footnote 144 This allowed Hamilton to speak to the so-called nature of competing forms of social organization. He believed that ‘biology might warn that if the final aim is a state of perfect communism[,] the best way of getting there is not to legislate private property out of existence in one year’. In such a case, ‘certain deep rooted feelings about property’ made it reasonable to predict ‘that chaos and anarchy would be the almost certain result’.Footnote 145

Conclusion

Inclusive fitness may be regarded by some as a scientific theory that was ahead of its time or, indeed, timeless. However, the theory, as well as the meaning Hamilton intended it to have for the human world, is better understood against its social and political background. Hamilton was certainly no political ideologue, but he earnestly believed that scientific knowledge should be used to inform a new social order. In devising a universal theory to explain the limits of pro-social behaviours through his theory of inclusive fitness, he rejected utopian visions that human nature was malleable enough to facilitate the fulfilment of political ideals of social harmony. Although he did not offer a biological system of morality, he nevertheless endorsed the use of evolutionary theory to guide policy. In doing so, he aimed to establish the primacy of the scientific ‘expert’ on human nature over competing types. Alternative sources of policy recommendations, he maintained, were not just overly idealistic – they would prove ultimately and irrevocably destructive. It was Hamilton's long-standing commitment to this belief that drove him to advocate for an evolutionary understanding of human society from the 1950s to the 1990s. For him, the only way to move forward was to cast cultural myths aside: it did not matter what ‘we may feel about it, all the evidence shows that an inflexible basis [of human behaviour] is really there’.Footnote 146

Footnotes

1 For one of the most contentious examples of this debate see Ruse, Michael, ‘The romantic conception of Robert J. Richards’, Journal of the History of Biology (2004) 37, pp. 3–23; Richards, Robert J., ‘Michael Ruse's design for living’, Journal of the History of Biology (2004) 37, pp. 25–38.

2 A.J. Lustig, ‘Introduction’, in A.J. Lustig, Robert J. Richards and Michael Ruse (eds.), Darwinian Heresies, Cambridge: Cambridge University Press, 2004, p. 4.

3 E.O. Wilson, Sociobiology: The New Synthesis, Cambridge, MA: Harvard University Press, 2000; first published 1975, p. 4.

4 Richard Dawkins, The Selfish Gene, New York and Oxford: Oxford University Press, 1976, p. 3.

5 Dawkins, op. cit. (4), p. 2.

6 Elizabeth Allen, Barbara Beckwith, Jon Beckwith, Steven Chorover, David Culver et al., ‘Against “sociobiology”,’ New York Review of Books, 13 November 1975.

7 E.O. Wilson, ‘For sociobiology’, New York Review of Books, 11 December 1975. Charlotte Sleigh examined Wilson's reticence to endorse analogies between ants and humans and whether we should take these claims at face value in Six Legs Better: A Cultural History of Myrmecology, Baltimore: Johns Hopkins University Press, 2007, esp. pp. 217, 225. Sleigh also highlighted the influence of Caryl Haskins on Wilson, and it is worthwhile to note that Haskins wrote to Hamilton shortly after the Man and Beast conference to congratulate him on his ‘evocative paper at the Symposium’. C.P. Haskins to W.D. Hamilton, 19 May 1969, W.D. Hamilton papers, British Library, London (subsequently HP), Z1X89/1/6.

8 Dawkins, Richard, ‘In defence of selfish genes’, Philosophy (1981) 56, pp. 556–573, 556.

9 Richard Dawkins, An Appetite for Wonder: The Making of a Scientist, London: Transworld, 2014, p. 259; Dawkins, op. cit. (8), p. 558.

10 Hamilton, W.D., ‘The genetical evolution of social behavior. I’, Journal of Theoretical Biology (1964) 7, pp. 1–16, 16.

11 Hamilton, W.D., ‘The evolution of altruistic behavior’, American Naturalist (1963) 97, pp. 354–356; Hamilton, op. cit. (10); Hamilton, , ‘The genetical evolution of social behaviour. II’ Journal of Theoretical Biology (1964) 7, pp. 17–52.

12 See the quotations he claimed ‘started me on this whole business’ in W.D. Hamilton, entry in ‘Tonbridge School. Mathematics’, 4 March 1958, HP, Z1X42/1/6.

13 W.D. Hamilton, ‘New aspects of evolution and their relation to man and human affairs’, n.d., c.1977–1978, HP, Z1X73/1/12.

14 Charles Darwin, On the Origin of Species (ed. Joseph Carroll), Ontario: Broadview, 2003, p. 242.

15 Darwin, op. cit. (14), p. 243.

16 A.J. Lustig, ‘Darwin's difficulties’, in Michael Ruse and Robert J. Richards (eds.), The Cambridge Companion to the “Origin of Species”, Cambridge: Cambridge University Press, 2009, p. 127.

17 W.D. Hamilton, ‘W.D. Hamilton’, n.d., c.1959–1962, HP, Z1X74/1/9.

18 W.D. Hamilton, ‘Parental altruism in birds etc’, n.d., HP, Z1XUN/1/7. See also Hamilton, handwritten note, ‘Altruistic action pearl: nat. hist. of pop.’, n.d., c.1959–1964, HP, Z1X74/1/9.

19 Niko Tinbergen to W.D. Hamilton, 29 October 1980, HP, Z1X64/1/19.

20 James G. Paradis and George C. Williams, Evolution and Ethics, Princeton, NJ: Princeton University Press, 1989, pp. 190–191.

21 See, for example, G.C.L. Bertram, Adam's Brood: Hopes and Fears of a Biologist, London: P. Davies, 1959.

22 Robert Ardrey, African Genesis: A Personal Investigation into the Animal Origins and Nature of Man, London: Collins, 1961, p. 349; appears on note written by W.D. Hamilton, n.d., HP, Z1X40/1/2.

23 F. Fraser Darling, ‘Man and nature: the first of the Reith Lectures’, The Listener, 13 November 1969, pp. 653–656, 655.

24 See, for example, Peter J. Bowler, Evolution: The History of an Idea, Berkeley: University of California Press, 1989, p. 329; Michael Ruse, Monad to Man: The Concept of Progress in Evolutionary Biology, Cambridge, MA and London: Harvard University Press, 1996, p. 458; Andrew Brown, The Darwin Wars: How Stupid Genes Became Selfish Gods, London: Simon and Shuster, 1999, p. 83; Michael Ruse, Darwinism and Its Discontents, Cambridge and New York: Cambridge University Press, 2006, p. 48. The assumed relationship between the theory of inclusive fitness and social insects dates to as early as 1965. See, for example, A.S. Rand to W.D. Hamilton, 14 March 1965, HP, Z1X89/1/1. For a draft of Hamilton's theory that precedes his understanding of social insects see W.D. Hamilton, ‘Natural selection involving competition between relatives’, n.d., c.1960–1962, HP, Z1XUN/2.

25 W.D. Hamilton to T.H. Clutton-Brock, 2 July 1991, HP, Z1X88/2/6.

26 For a more thorough discussion of the development of Hamilton's theory of inclusive fitness see Swenson, Sarah A., ‘“From man to bacteria”: W.D. Hamilton, the theory of inclusive fitness, and the post-war social order’, Studies in History and Philosophy of Biological and Biomedical Sciences (2015) 49, pp. 45–54.

27 Dawkins, op. cit. (4), p. 10.

28 Wilson, op. cit. (7).

29 See, for example, Dawkins, op. cit. (9), p. 282; Ullica Segerstrale, Defenders of the Truth: The Sociobiology Debate, New York: Oxford University Press, 2000, p. 133; Wilson, op. cit. (3), p. vi.

30 See, for example, Mark E. Borrello, Evolutionary Restraints: The Contentious History of Group Selection, Chicago: The University of Chicago Press, 2010; Jumonville, Neil, ‘The cultural politics of the sociobiology debate’, Journal of the History of Biology (2002), pp. 569–593; Shavit, Ayelet, ‘Shifting values partly explain the debate over group selection’, Studies in History and Philosophy of Biological and Biomedical Sciences, (2004), pp. 697–720; Michael Yudell, Race Unmasked: Biology and Race in the Twentieth Century, New York: Columbia University Press, 2014.

31 Hamilton to Clutton-Brock, op. cit. (25).

32 W.D. Hamilton, recorded lecture for Natural Selection and Social Theory, 22 February 1978, HP.

33 W.D. Hamilton to John Pfeiffer, 16 February 1965, HP, Z1X89/1/1, underlining in original.

34 W.D. Hamilton, Human Diversity (1964) by Kenneth Mather, Population Studies (November 1965), p. 203, HP, Z1X37/1/8.

35 W.D. Hamilton, Narrow Roads of Gene Land, 3 vols., Oxford: Oxford University Press, 1996–2005, vol. 1, pp. 194–195.

36 Hamilton to Pfeiffer, op. cit. (33).

37 Hamilton to Pfeiffer, op. cit. (33); for an earlier discussion of Hamilton's interest in R.A. Fisher's account of human evolution see W.D. Hamilton to Bettina Hamilton, 21 November 1957, HP, Z1X42/1/16.

38 Hamilton to Pfeiffer, op. cit. (33).

39 W.D. Hamilton, entry in ‘Rough notes’, 14 October 1954, HP, Z1XUN/4, underlining in original.

40 W.D. Hamilton to Mary Hamilton [Bliss], n.d., c. September 1956, HP, Z1X42/1/17.

41 Hamilton, op. cit. (34).

42 See, for example, in one British periodical in 1954 alone, H.S. Deighton, ‘A problem in race relations’, The Listener, 13 May 1954, pp. 809–810; Norman Goodall, ‘Church and race in South Africa’, The Listener, 20 May 1954, pp. 55–56; Alistair Cooke, ‘Negro citizens in the U.S.A.’, The Listener, 10 June 1954, pp. 996–997; Walter Kolarz, ‘The racial problem in the United States’, The Listener, 14 October 1954, pp. 601–602; Ronald E. Robinson, ‘The racial problem in Africa’, The Listener, 16 December 1954, pp. 1051–1052.

43 Brian Harrison, Seeking a Role: The United Kingdom 1951–1970, Oxford: Oxford University Press, 2009, pp. 83–84; Mel Risebrow, ‘An analysis of the responses of British government to coloured colonial immigration during the period 1945–1951’, unpublished undergraduate thesis, University of East Anglia, 1983, cited in Peter Hennessy, Having It So Good: Britain in the Fifties, London: Penguin, 2007, p. 222.

44 Hennessy, op. cit. (43), p. 222.

45 Lord Salisbury to Oliver Lyttelton, 19 March 1954, quoted in Hennessy, op. cit. (43), p. 224.

46 Harrison, op. cit. (43), p. 220.

47 W.D. Hamilton to Bettina Hamilton, n.d., HP, Z1X42/1/16; W.D. Hamilton to ‘David’, n.d., c. June 1957, HP, Z1X42/1/1.

48 Harrison, op. cit. (43), p. 224.

49 Hamilton to ‘David’, op. cit. (47).

50 Hamilton to ‘David’, op. cit. (47).

51 Hamilton to ‘David’, op. cit. (47).

52 Hamilton to ‘David’, op. cit. (47).

53 W.D. Hamilton to Bettina Hamilton, n.d., HP, Z1X42/1/16.

54 Hamilton to Bettina Hamilton, op. cit. (53).

55 W.D. Hamilton to Bettina Hamilton and A.M. Hamilton, 3 September 1963, HP, Z1X42/1/13.

56 For extended discussion of the biology and biologizing of ‘race’ throughout the twentieth century see Yudell, op. cit. (30).

57 Julian Huxley, The Human Crisis, Washington: University of Washington Press, 1963, pp. 75, 79.

58 Sommer, Marianne, ‘Biology as technology of social justice in interwar Britain: arguments from evolutionary history, heredity, and human diversity’, Science, Technology, & Human Values (2014) 39, pp. 561–586, 565.

59 Julian Huxley, Evolutionary Ethics, Oxford: Oxford University Press, 1943, p. 59.

60 L. Harrison Matthews, ‘Overt fighting in mammals’, in J.D. Carthy and F.J.G. Ebling (eds.), The Natural History of Aggression, London: Academic Press, 1964, pp. 22–34; HP, Z1X10/1/19.

61 W.D. Hamilton, note in Matthews, op. cit. (60).

62 W.D. Hamilton, ‘Akar, J. (1969)’, n.d., HP, Z1X40/1/1.

63 W.D. Hamilton, ‘Selection of selfish and altruistic behaviour in some extreme models … Abstract’, n.d., c.1969, HP, Z2X29/1/8.

64 W.D. Hamilton, ‘Lorenz, K. (1966) on aggression’, n.d., HP, Z1X40/1/1, underlining in original.

65 Hamilton, op. cit. (64).

66 W.H. Auden, ‘Books of the year: some personal choices’, The Observer, 18 December 1966, p. 23.

67 Adam Raphael, ‘Violence on the roads’, The Guardian, 17 November 1967, p. 10.

68 ‘Paperback pickings’, The Guardian, 26 January 1968, p. 6; Elizabeth Elliott, ‘Letters to the editor’, The Guardian, 28 April 1969, p. 8.

69 S. Dillon Ripley to Henry Allen Moe, draft, n.d., Seminar Records, Smithsonian Institution archives, Washington, DC (subsequently SR), RU000494/3.

70 J.F. Eisenberg, ‘Acknowledgments’, in J.F. Eisenberg and Wilton S. Dillon (eds.), Man and Beast: Comparative Social Behavior, Washington, DC: Smithsonian Institution Press, 1971, p. 13.

71 Ripley to Moe, op. cit. (69). Hamilton had read and reflected upon Robert Ardrey's first book on the nature of man, African Genesis (1961). There, Ardrey claimed that an understanding of human evolution, and especially anthropologist Raymond Dart's theories, would provide revolutionary insight into the human world.

72 S. Dillon Ripley to Harry F. Guggenheim, 14 October 1968, SR, RU000494/1.

73 S. Dillon Ripley, ‘Announcement’, 3 February 1969, SR, RU000494/3.

74 S. Dillon Ripley to members of the secretariat, 14 June 1967, SR, RU000494/4; Ripley to Guggenheim, op. cit. (72).

75 ‘An interpretation of comparative social behavior for public programs and popular education’, SR, RU000494/4.

76 ‘An interpretation of comparative social behavior’, op. cit. (75).

77 ‘An interpretation of comparative social behavior’, op. cit. (75).

78 ‘An interpretation of comparative social behavior’, op. cit. (75).

79 S. Dillon Ripley to David K.E. Bruce, 25 March 1969, SR, RU000494/4; William W. Warner to Mrs Miles Fitzalan Howard, 17 December 1968, SR, RU000494/4; James Orr to S. Dillon Ripley, 7 January 1969, SR, RU000494/4.

80 W.D. Hamilton, ‘Selection of selfish and altruistic behaviour in some extreme models’, n.d., c.1969, HP, Z2X29/1/8.

81 Hamilton, op. cit. (80).

82 Hamilton, op. cit. (80).

83 Hamilton, op. cit. (35), vol. 1, pp. 190–191.

84 Hamilton, op. cit. (80).

85 Hamilton, op. cit. (80).

86 Hamilton, op. cit. (63).

87 Hamilton, op. cit. (35), vol. 1, p. 186.

88 Alondra Nelson, Body and Soul: The Black Panther Party and the Fight against Medical Discrimination, Minneapolis: University of Minnesota Press, 2011, p. 5.

89 Ronald Reagan, quoted in ‘Riots and ’68’, National Review Bulletin, 15 August 1967, pp. 4–5, 5.

90 ‘The violence’, The Nation, 14 August 1967, p. 101.

91 See, for example, Philip A. McCombs, ‘Who is behind the race riots?’, National Review, 20 September 1966, pp. 934–935, 934.

92 ‘The Cleveland affair’, National Review, 13 August 1968, pp. 789–790, 789.

93 Robin Fox, Participant Observer: Memoir of a Transatlantic Life, New Brunswick and London: Transaction, 2004, p. 417; ‘Budget’, 27 April 1969, SR, RU000494/3; Ripley to Guggenheim, op. cit. (72).

94 S. Dillon Ripley to Douglas D. Bond, 9 January 1969, SR, RU000494/3.

95 Ripley to Bond, op. cit. (94).

96 ‘Financing the Symposium’, n.d., SR, RU000494/3. The Russell Sage Foundation is a private American foundation with a mission to improve living conditions. The Commonwealth Fund was founded in 1918, and in the 1960s it was especially concerned with improving health care in urban communities. The Alfred P. Sloan Foundation was founded in 1934, and aims to fund research that will improve science, technology or economic performance, and support public understanding of these fields. The author could not find more information about the Grant Foundation or the Luana Foundation at this time.

97 John A. Schneider to S. Dillon Ripley, 5 March 1969, SR, RU000494/3.

98 Paul R. Ignatius to S. Dillon Ripley, 4 April 1969, SR, RU000494/3.

99 Marshall K. Evans to S. Dillon Ripley, 31 March 1969, SR, RU000494/3.

100 Alfred R. Schneider to S. Dillon Ripley, 23 April 1969, SR, RU000494/3.

101 J.A. Linen to S. Dillon Ripley, 14 February 1969, SR, RU000494/3; see also W.M. Bennett to S. Dillon Ripley, 4 March 1969, SR, RU000494/3.

102 Harry F. Guggenheim to S. Dillon Ripley, 1 November 1968, SR, RU000494/1.

103 See articles held in SR, RU000494/3, including Herman Schaden, ‘Behavior of man and beast is topic at Smithsonian’, Washington Star, 23 March 1969; Phil Casey, ‘It's not that simple: man's aggressive inheritance questioned’, Washington Post, 15 May 1969; John Leo, ‘Expert says man can change in 10 generations’, New York Times, 15 May 1969.

104 Alan M. Kriegsman, ‘A pernicious source of confusion’, Washington Post, 17 May 1969, SR, RU000494/3. For a detailed account of Fulbright's life see Randall Bennett Woods, Fulbright: A Biography, Cambridge: Cambridge University Press, 1995.

105 Herman Schaden, ‘A mini-symposium: Fulbright and the scholars’, Washington Star, 16 May 1969, SR, RU000494/3.

106 Schaden, op. cit. (105).

107 Phil Casey, ‘Behaving better than we do’, Washington Post, 16 May 1969, SR, RU000494/3.

108 Ann Cottrell Free, ‘Meet Louis Halle, example of a vanishing species’, Washington Star, 25 May 1969, SR, RU000494/3.

109 Theodosius Dobzhansky, ‘The present evolution of man’, Scientific American (1960) 203, p. 206.

110 Louis J. Halle, quoted in William Delaney, ‘A matter of manners: attitude shift held man's key to survival’, Washington Star, 17 May 1969, SR, RU000494/3.

111 J. illiam Fulbright, quoted in Delaney, op. cit. (110).

112 Yudell, op. cit. (30), has characterized the relationship between sociobiology and racism similarly.

113 Hamilton, op. cit. (17).

114 W.D. Hamilton, ‘Penultimate lecture 1970’, n.d., c.1970, HP, Z1X90/1/22; Hamilton, bibliography for Social Biology lectures, n.d., c.1971, HP, Z1X90/1/7.

115 W.D. Hamilton, ‘Animals in the prisoner's dilemma’, 1971, HP, Z2X29/1/12.

116 W.D. Hamilton, ‘Population control’, New Scientist, 20 October 1969, pp. 260–261.

117 W.D. Hamilton, ‘Lecture 12’, n.d., c.1971, HP, Z1X90/1/13.

118 W.D. Hamilton, ‘Incest of mice and men’, 4 August 1974, HP, Z2X29/1/13.

119 W.D. Hamilton, manuscript with no title, n.d., c. early 1970s, HP, Z1X90/1/18.

120 Alan Grafen, ‘William Donald Hamilton’, in Hamilton, op. cit. (35), vol. 3, p. 431.

121 See, for example, E.O. Wilson, ‘Slavery in ants’, Scientific American (1975) 232(6), pp. 32–36; Dawkins, op. cit. (8); Masters, Roger D., ‘Is sociobiology reactionary? The political implications of inclusive-fitness theory’, Quarterly Review of Biology (1982) 57(3), pp. 275–292; Richard Dawkins, ‘The better self can transcend the selfish gene’, The Observer, 15 October 1989, p. 61.

122 John Maynard Smith, review of ‘In the safety of confusion: the sociobiology debate’, New Scientist, 29 March 1979, p. 1051.

123 For a recent discussion of the naturalistic fallacy and its persistence see the recent ‘Focus’ section in Isis (2014) 105(3), pp. 569–616, featuring Brooke Holmes, ‘Greco-Roman ethics and the naturalistic fantasy’; Lorraine Daston, ‘The naturalistic fallacy is modern’; Matthew Stanley, ‘From ought to is: physics and the naturalistic fallacy; Erika Lorraine Milam, ‘A field study of con games’; Warwick Anderson, ‘Getting ahead of one's self? The common culture of immunology and philosophy’. Piers J. Hale, Political Descent: Malthus, Mutualism, and the Politics of Evolution in Victorian England, Chicago: The University of Chicago Press, 2014.

124 Hodgson, Geoffrey M., ‘Social darwinism in anglophone academic journals’, Journal of Historical Sociology (2004) 17, pp. 428–463; Daniel J. Kevles, In the Name of Eugenics: Genetics and the Uses of Human Heredity, New York: Knopf, 1985.

125 Nathaniel C. Comfort, The Science of Human Perfection: How Genes Became the Heart of American Medicine, New Haven: Yale University Press, 2012.

126 Sommer, Marianne, ‘From descent to ascent: the human exception in the evolutionary synthesis’, Nuncius (2010) 25, pp. 41–67. Here she refers to Julian Huxley, Theodosius Dobzhansky, Ernst Mayr and George Gaylord Simpson.

127 Borrello, op. cit. (30).

128 Eibl-Eibesfeldt, Irenäus, ‘The fighting behavior of animals’, Scientific American (1961) 205, pp. 117–122.

129 Corning, Peter A., ‘Evolution and ethics … an idea whose time has come?’, Journal of Social and Evolutionary Systems (1996) 19(3), pp. 277–285, 277–278.

130 Corning, op. cit. (129).

131 Robert Trivers, recorded lecture for Natural Selection and Social Theory, 19 April 1978, HP.

132 See especially Lee Alan Dugatkin, The Altruism Equation: Seven Scientists Search for the Origins of Goodness, Princeton, NJ: Princeton University Press, 2006, pp. x, 94; Grafen, op. cit. (120), p. 424.

133 Ullica Segerstrale, Nature's Oracle: The Life and Work of W.D. Hamilton, Oxford: Oxford University Press, 2013, p. 3.

134 Segerstrale, op. cit. (133), p. 5.

135 Marek Kohn, A Reason for Everything: Natural Selection and the English Imagination, London: Faber and Faber, 2004, pp. 23–24; A.J. Lustig, ‘William Donald Hamilton’, in New Dictionary of Scientific Biography, Detroit: Charles Scribner's Sons, 2008, pp. 225–235.

136 Segerstrale, op. cit. (133), p. 334.

137 Grafen, op. cit. (120), p. 447.

138 Trivers, op. cit. (131).

139 Trivers, op. cit. (131).

140 As he did in Robert Trivers, recorded lecture for Natural Selection and Social Theory, 1 February 1978, HP.

141 Robert Trivers to W.D. Hamilton, 27 May 1977, HP, Z1X69/1/12.

142 Trivers to Hamilton, op. cit. (141).

143 W.D. Hamilton to E.O. Wilson, 13 December 1974, HP, Z1X69/1/12.

144 W.D. Hamilton, ‘3 Nov. 1977’, HP, Z1X90/1/18.

145 Hamilton, op. cit. (144).

146 W.D. Hamilton, ‘Outline of genetics course for third year zoologists’, n.d., c. early 1970s, HP, Z1X90/1/21.