When both strategy and beliefs are involved, the interaction between them can be explored, as in James Morrows paper. Morrow(p. 24)discusses the following paradox: "Why is law in the form of treaties necessary if the parties already share complete understanding of all possible responses to all contingencies? He points out that"the concept of equilibrium in game theory provides no guidance about the paradox because it assumes a common conjecture among the players. " As expressed by Thomas Schelling, the issue is how"focal points"are arrived at around which expectations converge; in the language of David Lewis, how do "conventions"come about? In th language of social construction, game theory does not tell us how understandings of reality are socially constructed -for example, why certain engraved pieces of green paper can be exchanged for valuable goods and services, while others cannot. The common knowledge produced by social processes provides a point of complementarity between constructivist thinking, which seeks to explain common knowledge or common conjectures, and game theory, which relies on it to solve games of strategic interaction Rational-Choice Theory as Puzzle-Generator At this point, the reader may recall the perhaps-apocryphal story told about the writer Gertrude Stein, on her deathbed. She asked her long-time friend, Alice B. Toklas what is the answer? ""Receiving no reply, Stein then said, "Well, then, what is the question? "In my judgment, rational-choice theory is unexcelled at asking questions. Its relentless skepticism is valuable, undermining conventional answers, critiquing analytical complacency, and demanding deepening of explanations, asking that exogenous factor causal mechanisms generates many research questions, not about the existence any be made endogenous, consistent with the premises of the theory. Its identification precise character of these mechanisms but about the conditions under which they operate and to what effect. Often opposite mechanisms are at play in a given situation, generating different expectations about behavior. Hence in the end, many of these seems worthwhile to list a few of them, even if answers remain elusive, uestions. it o questions will only have empirical answers, to be arrived at through well-designed ar painstaking research. However, since this volume is rich in promisin 27 James D. Morrow, "The Laws of War, Common Conjectures, and Legal Systems in International Politics, "this volume, pp. Thomas C Schelling, The Strategy of Conflict( Cambridge: Harvard University Press, 1960); David K Lewis, Comvenmtion: A Philosophical Study( Cambridge: Harvard University Press, 1969) The example is John R Searles. The Construction of Social Reality(New York: Free Press, 1995). On social constructivism and international relations, see Alexander Wendt, Social Theory of international Politics( Cambridge: Cambridge University Press, 1999). On this point see Peter J Katzenstein, RobertO. Keohane and Stephen Krasner, "International Organization and the Study of World Politics, "in Katzenstein et al., Exploration and Contestation, cited, fn.7,pp.40-42. sI The most recent special issue of International Organization(volume 55, no 4; Autumn 2001)is on"The Rational Design of International Institutions"(edited by Barbara Koremenos, Charles Lipson, and Duncan nidal). It raises a number of interesting questions, generated by rational-choice theory, about institutional design. Particularly novel is its attention to flexibility, defined (p. 773)as how institutional rules accommodate new circumstances; that institutional design helps actors deal with noise in the system(p. 1061).10 When both strategy and beliefs are involved, the interaction between them can be explored, as in James Morrow’s paper.27 Morrow (p. 24) discusses the following paradox: “Why is law in the form of treaties necessary if the parties already share a complete understanding of all possible responses to all contingencies?” He points out that “the concept of equilibrium in game theory provides no guidance about the paradox because it assumes a common conjecture among the players.” As expressed by Thomas Schelling, the issue is how “focal points” are arrived at around which expectations converge; in the language of David Lewis, how do “conventions” come about?28 In the language of social construction, game theory does not tell us how understandings of reality are socially constructed – for example, why certain engraved pieces of green paper can be exchanged for valuable goods and services, while others cannot.29 The common knowledge produced by social processes provides a point of complementarity between constructivist thinking, which seeks to explain common knowledge or common conjectures, and game theory, which relies on it to solve games of strategic interaction.30 Rational-Choice Theory as Puzzle-Generator At this point, the reader may recall the perhaps-apocryphal story told about the writer Gertrude Stein, on her deathbed. She asked her long-time friend, Alice B. Toklas, “what is the answer?” Receiving no reply, Stein then said, “Well, then, what is the question?” In my judgment, rational-choice theory is unexcelled at asking questions. Its relentless skepticism is valuable, undermining conventional answers, critiquing analytical complacency, and demanding deepening of explanations, asking that exogenous factors be made endogenous, consistent with the premises of the theory. Its identification of causal mechanisms generates many research questions, not about the existence and precise character of these mechanisms but about the conditions under which they operate, and to what effect. Often opposite mechanisms are at play in a given situation, generating different expectations about behavior. Hence in the end, many of these questions will only have empirical answers, to be arrived at through well-designed and painstaking research. However, since this volume is rich in promising questions, it seems worthwhile to list a few of them, even if answers remain elusive.31 27 James D. Morrow, “The Laws of War, Common Conjectures, and Legal Systems in International Politics,” this volume, pp. -- . 28 Thomas C. Schelling, The Strategy of Conflict (Cambridge: Harvard University Press, 1960); David K. Lewis, Convention: A Philosophical Study (Cambridge: Harvard University Press, 1969). 29 The example is John R. Searle’s. The Construction of Social Reality (New York: Free Press, 1995). On social constructivism and international relations, see Alexander Wendt, Social Theory of International Politics (Cambridge: Cambridge University Press, 1999). 30 On this point see Peter J. Katzenstein, Robert O. Keohane and Stephen Krasner, “International Organization and the Study of World Politics,” in Katzenstein et al., Exploration and Contestation, cited, fn. 7, pp. 40-42. 31 The most recent special issue of International Organization (volume 55, no. 4; Autumn 2001) is on “The Rational Design of International Institutions” (edited by Barbara Koremenos, Charles Lipson, and Duncan Snidal). It raises a number of interesting questions, generated by rational-choice theory, about institutional design. Particularly novel is its attention to flexibility, defined (p. 773) as how institutional rules accommodate new circumstances; that is, how institutional design helps actors deal with noise in the system (p. 1061)