Melvyn Bragg and his guests discuss game theory, the mathematical study of decision-making. First formulated in the 1940s, the discipline entails devising 'games' to simulate situations of conflict or cooperation. It allows researchers to unravel decision-making strategies, and even to establish why certain types of behaviour emerge. Some of the games studied in game theory have become well known outside academia - they include the Prisoner's Dilemma, an intriguing scenario popularised in novels and films, and which has inspired television game shows. Today game theory is seen as a vital tool in such diverse fields as evolutionary biology, economics, computing and philosophy. With:Ian StewartEmeritus Professor of Mathematics at the University of WarwickAndrew ColmanProfessor of Psychology at the University of LeicesterRichard BradleyProfessor of Philosophy at the London School of Economics and Political Science.Producer: Thomas Morris.