Iam grateful to Michael Rustin for his considered discussion of my Treatise on Social Theory footnote1 and to the Editors of the nlr for giving me the opportunity to respond to him.

Rustin is right both about the objective with which I embarked on the trilogy and about the extent to which its second volume, in particular, has been overtaken, as well as vindicated, by recent advances in neo-Darwinian evolutionary theory. In 1986, when, as a result of the refusal of the Soviet authorities to grant a visa to A.M. Khazanov, the eminent Russian expert on nomadic pastoralism, I gave the British Academy’s Radcliffe-Brown Lecture in his stead,footnote2 I used the opportunity to stake a claim for a neo-Darwinian—but not sociobiological—sociology before I was beaten to it by somebody else. But I need not have worried. Despite a title which deliberately echoed that of Darwin’s and Wallace’s joint presentation to the Linnaean Society in 1858, the lecture provoked no one either to dismiss it as unoriginal or to denounce it as erroneous. So far as I am aware, it has nowhere been cited in print except by myself. It is true that the subsequent publication of the second volume of the trilogy brought me an invitation to give a plenary address to the American Sociological Association in 1992. But, on this side of the Atlantic, at any rate, I continued to feel that I was a lone voice preaching to the deaf.

I have, accordingly, been as surprised by the attention more recently accorded to my approach to macrosociological theory as I was by its previous neglect. I have by now been given the opportunity to address a plenary session of the World Sociological Congress in Bielefeld,footnote3 a Darwin Seminar at the London School of Economics, an Academia Europaea seminar in Basel, an annual meeting of the Swedish Sociological Association in Stockholm, a British Academy discussion meeting in London, a British Sociological Association panel session in Glasgow, and even a public lecture audience in my own university of Cambridge under the auspices of the Social Anthropology Department. The clear impression with which these occasions have left me is of being in the middle of a classic Kuhnian paradigm-shift. Some of those to whom I find myself talking have already made significant contributions to their chosen field of behavioural science from within the neo-Darwinian paradigm. But others are exemplary cases of (in Kuhn’s term) ‘hold-outs’—the ‘older and more experienced scientists’ who, Kuhn suggests, ‘may resist indefinitely’ when confronted with a novel paradigm which they dislike.footnote4 And, in between, there are the people who wonder quite what it is all about but suspect that they are being drawn into one of those ‘deep debates’, as Kuhn described them, ‘over legitimate methods, problems and standards of solution’ which, however, ‘serve rather to define schools than produce agreement’.footnote5

In considering the implications of the neo-Darwinian paradigm for the human sciences, it is important to distinguish the direct application of the theory of natural selection to aspects of human social behaviour previously thought beyond its scope from the application of the concepts of heritable variation and competitive selection to sociology and social anthropology at a different level.

It is quite consistent for sociologists and social anthropologists to accept the results of sociobiological research on the strength of the evidence presented without going on to accept the reductionist claims put forward by E.O. Wilson in the name of ‘consilience’.footnote6 Sociobiologists, biological anthropologists, evolutionary psychologists, and behaviour geneticists have, in recent years, published numerous well-attested—and some less well-attested—findings which bear directly on one or another aspect of human social behaviour, and, as Rustin rightly says, sociologists cannot afford simply to ignore them. But sociobiology has, at least for the present, little or nothing to contribute to the sort of questions about state formation, or class conflict, or the displacement of slavery or serfdom by wage labour which are the concerns of a comparative and historical sociologist like myself.

More relevant to sociologists and social anthropologists are recent developments in evolutionary game theory, and here I accept that my second volume failed to give them the attention they deserve. It was not that I knew nothing about game theory, since, already in the 1960s, Amartya Sen and I had published a jointly-authored contribution to the burgeoning literature on the ‘prisoner’s dilemma’.footnote7 I was also aware of the irony that, although von Neumann and Morgenstern had expected the theory of games to be useful particularly to economists, it was to biological theory that it had turned out to have more to offer.footnote8 But I did not then appreciate just how much game theory would contribute both formally and experimentally to the study of the evolution of reciprocal altruism and maintenance of stable social contracts in human groups—topics of unmistakable relevance to any analysis of the interaction between relations of domination and of co-operation in societies of different kinds.

An equally important omission was my failure to consider the nature of the relation of cultural selection—that is, the transmission to adjacent or successive populations of mutant beliefs and values through imitation and learning—to social selection. Although I had come across the early work of Boyd and Richerson, I had not appreciated the value of their modelling of cultural transmission as an inheritance system,footnote9 I had not read any of the seminal papers of the American psychologist Donald Campbell,footnote10 and I had not even tried to explore in any detail the relationship, in the evolution of human communities, institutions, and societies of different kinds, between interpersonal relationships of influence and institutional relationships of power.footnote11