This Special Issue is devoted to the recently revived debate which explores the impact of Darwinian thought on the social sciences. The upper classes’ competitive liberal world view in Victorian England has been said to have influenced Darwin in conceiving his theory of natural selection. In the late nineteenth and early twentieth centuries, however, the theory of natural selection for its part became an argument in liberal thought. The political philosophy of such writers as Herbert Spencer and William Graham Sumner sought to extend the theory to the functioning of human society. They aimed at legitimizing an unimpeded exercise of competitive forces as a means to induce human progress. The more this interpretation, now labeled Social Darwinism, inspired the eugenics movement and the worst racist excesses, the more it discredited Darwinian thought in the social sciences altogether. As a consequence, for the main part of the twentieth century the social sciences and their philosophy refused to address the question of how relevant the evolutionary agenda is for them.

In the last few decades, however, evolutionary thought has once again begun to feature prominently in some sub-disciplines of the social sciences. Evolutionary anthropology and evolutionary psychology clearly draw on evolutionary biology. Economics and the social sciences more generally develop a renewed interest in the inherited parts of human social and economic behavior which invites reconsidering existing explanations of that behavior. In the wake of these new developments, longstanding disputes about the conceptual, methodological, and normative implications that Darwinian thought may have for economics and the social sciences make a re-appearance. The exciting new horizons that open up with the revived debate are center stage in the contributions to the present Special Issue. Given the potential for conflict over what approach to take, controversial views are to be expected and, in fact, have some counterparts in the past. Accordingly, the present contributions highlight controversial views arising from present day discussions as well as from some historical precedents.

In the attempt to identify a new frontier of interdisciplinary research, the contributions to this Special Issue come from authors with a disciplinary background in economics, in political science, in philosophy, and in the history of biology. Several of the papers (Arnhart, Reydon, Schnellenbach, Levit, Schabas) have emerged from a Workshop on “Liberalism and the Evolutionary Agenda” held in Freiburg, Germany in December 2013. It was co-organized by the Max Planck Institute of Economics (Jena) and the Walter Eucken Institute (Freiburg). The generous financial support of the workshop by the Fritz Thyssen Foundation in Cologne is gratefully acknowledged. Further thanks go to the anonymous reviewers of this Journal whose expertise across the relevant disciplines has helped to make stimulating papers even more interesting.