514 International Organization Grounding liberal theory in a set of core social scientific assumptions helps over- come a disjuncture between contemporary empirical research on world politics and the language employed by scholars to describe IR as a field.Liberal hypotheses stressing variation in state preferences play an increasingly central role in IR scholar- ship.These include explanations stressing the causal importance of state-society re- lations as shaped by domestic institutions(for example,the "democratic peace"),by economic interdependence(for example,endogenous tariff theory),and by ideas about national,political,and socioeconomic public goods provision(for example,theories about the relationship between nationalism and conflict).Liberal hypotheses do not include,for reasons clarified later,functional regime theory.Yet the conceptual lan- guage of IR theory has not caught up with contemporary research.IR theorists con- tinue to speak as if the dominant theoretical cleavage in the field were the dichotomy between realism and ("neoliberal")institutionalism.The result:liberal IR theory of the kind outlined earlier is generally ignored as a major paradigmatic alternative. Worse,its lack of paradigmatic status has permitted critics to caricature liberal theory as a normative,even utopian,ideology.Postwar realist critics such as Hans Morgenthau and E.H.Carr took rhetorical advantage of liberalism's historical role as an ideology to contrast its purported altruism(“idealism,“legalism,”“moralism,” or "utopianism")with realism's "theoretical concern with human nature as it actu- ally is [and]historical processes as they actually take place."Forty years later,little has changed.Robert Gilpin's influential typology in international political economy juxtaposes a positive mercantilist view("politics determines economics")against a narrower and conspicuously normative liberal one ("economics should determine politics").Kenneth Waltz,a realist critic,asserts that "if the aims...of states be- come matters of...central concern,then we are forced back to the descriptive level; and from simple descriptions no valid generalizations can be drawn."2 Liberals have responded to such criticisms not by proposing a unified set of positive social scientific assumptions on which a nonideological and nonutopian liberal theory can be based,as has been done with considerable success for realism and institutionalism,but by conceding its theoretical incoherence and turning instead to intellectual history.It is widely accepted that any nontautological social scientific theory must be grounded in a set of positive assumptions from which arguments,explanations,and predictions can be de- rived.3 Yet surveys of liberal IR theory either collect disparate views held by "classical" liberal publicists or define liberal theory teleologically,that is,according to its purported optimism concerning the potential for peace,cooperation,and intemational institutions in world history.Such studies offer an indispensable source of theoretical and normative inspi- ration.Judged by the more narrowly social scientific criteria adopted here,however,they do not justify reference to a distinct "liberal"IR theory. Leading liberal IR theorists freely concede the absence of coherent microfounda- tional assumptions but conclude therefrom that a liberal IR theory in the social scien- 1.See Morgenthau 1960,4;Keohane 1989,68,n.17;and Howard 1978,134. 2.See Waltz 1979,65,27;Gilpin 1975,27 (emphasis in original);and Gilpin 1987. 3.See Bueno de Mesquita 1996,64-65;and Keohane 1986.514 International Organization Grounding liberal theory in a set of core social scientific assumptions helps over￾come a disjuncture between contemporary empirical research on world politics and the language employed by scholars to describe IR as a field. Liberal hypotheses stressing variation in state preferences play an increasingly central role in IR scholar￾ship. These include explanations stressing the causal importance of state-society re￾lations as shaped by domestic institutions (for example, the "democratic peace"), by economic interdependence (for example, endogenous tariff theory), and by ideas about national, political, and socioeconomic public goods provision (for example, theories about the relationship between nationalism and conflict). Liberal hypotheses do not include, for reasons clarified later, functional regime theory. Yet the conceptual lan￾guage of IR theory has not caught up with contemporary research. IR theorists con￾tinue to speak as if the dominant theoretical cleavage in the field were the dichotomy between realism and ("neoliberal") institutionalism. The result: liberal IR theory of the kind outlined earlier is generally ignored as a major paradigmatic alternative. Worse, its lack of paradigmatic status has permitted critics to caricature liberal theory as a normative, even utopian, ideology. Postwar realist critics such as Hans Morgenthau and E. H. Carr took rhetorical advantage of liberalism's historical role as an ideology to contrast its purported altruism ("idealism," "legalism," "moralism," or "utopianism") with realism's "theoretical concern with human nature as it actu￾ally is [and] historical processes as they actually take place."' Forty years later, little has changed. Robert Gilpin's influential typology in international political economy juxtaposes a positive mercantilist view ("politics determines economics") against a narrower and conspicuously normative liberal one ("economics should determine politics"). Kenneth Waltz, a realist critic, asserts that "if the aims . . . of states be￾come matters of. . . central concern, then we are forced back to the descriptive level; and from simple descriptions no valid generalizations can be dra~n."~ Liberals have responded to such criticisms not by proposing a unified set of positive social scientific assumptions on which a nonideological and nonutopian liberal theory can be based, as has been done with considerable success for realism and institutionalism, but by conceding its theoretical incoherence and turning instead to intellectual history. It is widely accepted that any nontautological social scientific theory must be grounded in a set of positive assumptions from which arguments, explanations, and predictions can be de￾rived.3 Yet surveys of liberal IR theory either collect disparate views held by "classical" liberal publicists or define liberal theory teleologically, that is, according to its purported optimism concerning the potential for peace, cooperation, and international institutions in world history. Such studies offer an indispensable source of theoretical and normative inspi￾ration. Judged by the more narrowly social scientific criteria adopted here, however, they do not jusa reference to a distinct "liberal" IR theory. Leading liberal IR theorists freely concede the absence of coherent microfounda￾tional assumptions but conclude therefrom that a liberal IR theory in the social scien- 1. See Morgenthau 1960,4; Keohane 1989,68, n. 17; and Howard 1978, 134. 2. See Waltz 1979,65,27; Gilpin 1975, 27 (emphasis in original); and Gilpin 1987. 3. See Bueno de Mesquita 1996,64-65; and Keohane 1986