The notion of rationality
12 May 2009
Professor Samir Okasha in the Department of Philosophy has recently been awarded a major grant to study the philosophical implications of current developments in evolutionary biology.
Okasha’s concept of the role of the philosophy of science – clarifying scientific concepts – assumes a fairly sharp distinction between empirical and conceptual questions, but this does not imply that philosophers should be mere passive observers of science. On the contrary, he argues that they can make an invaluable contribution to scientific debates, as long as they are suitably informed. His own field of research is highly interdisciplinary in that he actively collaborates with people from biology, social science and economics, because there are many areas where these disciplines overlap. For example, the ways in which co-operation can arise among basically selfish biological organisms have really close analogues in the social sciences and in economics where those very same questions arise about how an individual’s self-interest can be reconciled with the good of the whole. To explore these ideas further, he has started a major new collaborative project with Ken Binmore, a well-known economist and game theorist, and one of the founders of the modern economic theory of bargaining.
Philosophers can make an invaluable contribution to scientific debates
The overall aim of the project is to study the philosophical implications of recent work in evolutionary biology on the topics of co-operation, social behaviour, and the conflict between individual and group interests. The project will look at the way those topics have been analysed in the social sciences, economics and the biological sciences, and try to look for parallels and interesting points of contrast. It ties in with trying to understand the nature of collective action, and the trade-off between individual self-interest and the common good of society as a whole. Such topics have long been of interest to political philosophers and to social scientists, who have traditionally studied them from the viewpoint of rational choice theory rather than evolutionary theory. Viewed the first way, the issue is whether a rational agent will ever choose to behave co-operatively, or to sacrifice their welfare for that of the group; viewed the second way, the question is whether such behaviours will ever be favoured by natural selection. One major goal of the project, therefore, is to understand the implications of this shift from a rational choice to an evolutionary perspective. In particular, there are striking links between Darwinian theory and rational choice theory, particularly in relation to strategic behaviour, since a notion of optimality is central to both.
The project straddles the philosophy of economics and biology roughly equally and will explore whether evolutionary considerations can help explain behaviour, such as co-operation and altruism, that are hard to account for from a traditional rational choice perspective. Economists have long wondered why it is that people who are supposed to be individually rational and maximisers of self-interest engage in apparently a-rational forms of behaviour by being altruistic, or by exhibiting other forms of irrationalities in their preferences such as heavily discounting the future in favour of the present, or by being strongly averse to risk. Thus altruistic or co-operative behaviour seems at odds with classical rational choice theory of economics.
There are striking links between Darwinian theory and rational choice theory
The second major goal of the project is to explore the implications of recent biological work on ‘evolutionary transitions in individuality’. Such transitions occur when a number of free-living biological units, originally capable of surviving and reproducing alone, form themselves into a co-operative whole, generating a new, higher-level individual. This process has happened repeatedly in the history of life, giving rise to the familiar biological hierarchy we see today (gene – chromosome – prokaryotic cell – eukaryotic cell – multi-celled organism – kin group – colony).
Evolutionary transitions raise a crucial question: why was it beneficial for the smaller units to give up their free-living existence and form an aggregate? How did natural selection reconcile the interests of the smaller units with the interests of the whole? Intriguingly, closely analogous issues have arisen in both philosophy and social science.
In particular, the potential conflict between individual and group interests, and the different ways of alleviating the conflict, has long been a central concern of political philosophers, political theorists and economists. Here, one of the key questions is whether the recent biological work on evolutionary transitions can help us understand the nature of human co-operative groups. For example, might the principles which explain the evolution of social insect colonies, in which the individuals work mainly for the good of the colony, also be applicable to human social groups?
Okasha intends to explore how an evolutionary perspective can help understand behaviours and phenomena
Theoretical work suggests that in order for an evolutionary transition to occur, mechanisms are needed to align the evolutionary interests of individuals with those of their groups. Do such mechanisms shed light on the widely discussed problem in political philosophy of how to reconcile the conflict between individual self-interest and group welfare? Finally, the project will explore whether the theory of evolutionary transitions illuminates traditional metaphysical debates about the ‘reality’ of human groups and societies. Some biologists argue that a collection of individuals only constitutes a ‘real’ evolutionary unit, rather than a mere aggregate, if policing mechanisms are in place to regulate the selfish tendencies of the individuals. Others have proposed that real evolutionary units must exhibit ‘emergent properties’. What are the broader metaphysical implications of these biological ideas?
Through this project, Okasha intends to explore how an evolutionary perspective can help understand behaviours and phenomena which, from the perspective of rational choice theory, look to be anomalous, and whether ultimately this may lead to new a understanding of the notion of rationality.