Logic and the Foundations of the Theory of Games and Decisions: Introduction*
This special issue of Knowledge, Rationality and Action contains a selection of papers presented at the sixth conference on “Logic and the Foundations of the Theory of Games and Decisions” (LOFT6), which took place in Leipzig, in July 2004. The LOFT conferences have been a regular biannual event since 1994.1 The first conference was hosted by the Centre International de Recherches Mathematiques in Marseille (France), the next four took place at the International Center for Economic Research in Torino (Italy) and the most recent one was hosted by the Leipzig Graduate School of Management in Leipzig (Germany). The LOFT conferences are interdisciplinary events that bring together researchers from a variety of fields: computer science, economics, game theory, linguistics, logic, mathematical psychology, philosophy and statistics. In its original conception, LOFT had as its central theme the application of logic, in particular modal epistemic logic, to foundational issues in the theory of games and individual decision-making. Epistemic considerations have been central to game theory for a long time. The expression interactive epistemology has been used in the game-theory literature to refer to the analysis of what individuals involved in a strategic interaction know about facts concerning the external world as well as facts concerning each other’s knowledge and beliefs. What is relatively new is the realization that the tools and methodology that were used in game theory are closely related to those already used in other fields, notably computer science and philosophy. Modal logic turned out to be the common language that made it possible to bring together different professional communities. The insights gained and the methodology employed in one field can benefit researchers in a different field. Indeed, new and active areas of research have sprung from the interdisciplinary exposure provided by the LOFT conferences.2 Over time the scope of the LOFT conferences has broadened to encompass other tools, besides modal logic, that can be used to shed light on the general issues of rationality and agency. Topics that have fallen within the LOFT umbrella include epistemic and