Hegemony theory and tariff levels 81 merits,and other behavior that would suggest that British decision makers allocated significant attention and effort to securing a more open trading system. Second,we ought to find British efforts to capitalize upon British bargaining advantages in order to secure the lowering of European states'tariffs.In particular,we ought to observe British efforts to link the tariff issue to bar- gaining over other issues,and to seek tariff reductions as a guid pro quo for British diplomatic,military,or economic support.We also ought to find instances of British attempts to use economic or even military coercive di- plomacy in efforts to secure relevant concessions on tariffs.In particular,we ought to find attempts to negotiate reciprocal,nongeneralizing tariff reductions (i.e.,treaties without a most-favored-nation clause). Third,we ought to find that these attempts were successful.Hegemonic stability theory makes claims not only about a hegemonic state's behavior but also about the outcome of its behavior.If the target states successfully resisted British initiatives or liberalized"voluntarily"(that is,in the absence of any attempts by Britain to induce them to do so),then the case for the theory would be considerably weakened. Assuming that this is a fair statement of the implications of current versions of hegemonic stability theory,an empirical finding counter to these predictions would imply that the theory as a whole does not constitute an adequate explanation for changes in mid 19th century tariff levels.However,such a finding would say nothing about the truth of specific components of various versions of hegemonic stability theory.It is indeed possible that many of these components are true but,even if they were not,those scholars who adhere to the epistemological strategy of Milton Friedman would no doubt contend that a demonstration of the falsity of component propositions in no way reflects upon the soundness of the theory.By testing implications, rather than components,such a contention simply cannot arise. We now briefly consider the evidence presented in some standard historical works on British commercial diplomacy in the 19th century.There is a lack of consensus among hegemonic stability theorists about the timing of the end of British hegemony.Hence I focus on British efforts to secure European adherence to an open trading system,rather than on possible later efforts to maintain that system.Since hegemonic stability theory posits hegemon- to-target influence as the mechanism for propagating an open trading system, the investigation centers on this process rather than on the origins of Britain's low tariff policy.(Whatever the origins of Britain's policy,the case for or against the theory clearly rests on whether the open trading system was propagated in the way the theory postulates.) In the period 1750-1815,Britain attempted to use the granting of pref- erential access to the British home market as a bargaining chip;in turn, Britain frequently sought preferential access to other markets when nego- tiating.This policy was officially ended by the Reciprocity of Duties Act ofHegemony theory and tariff levels 81 merits, and other behavior that would suggest that British decision makers allocated significant attention and effort to securing a more open trading system. Second, we ought to find British efforts to capitalize upon British bargaining advantages in order to secure the lowering of European states' tariffs. In particular, we ought to observe British efforts to link the tariff issue to bar￾gaining over other issues, and to seek tariff reductions as a quid pro quo for British diplomatic, military, or economic support. We also ought to find instances of British attempts to use economic or even military coercive di￾plomacy in efforts to secure relevant concessions on tariffs. In particular, we ought to find attempts to negotiate reciprocal, nongeneralizing tariff reductions (i.e., treaties without a most-favored-nation clause). Third, we ought to find that these attempts were successful. Hegemonic stability theory makes claims not only about a hegemonic state's behavior but also about the outcome of its behavior. If the target states successfully resisted British initiatives or liberalized "voluntarily" (that is, in the absence of any attempts by Britain to induce them to do so), then the case for the theory would be considerably weakened. Assuming that this is a fair statement of the implications of current versions of hegemonic stability theory, an empirical finding counter to these predictions would imply that the theory as a whole does not constitute an adequate explanation for changes in mid 19th century tariff levels. However, such a finding would say nothing about the truth of specific components of various versions of hegemonic stability theory. It is indeed possible that many of these components are true but, even if they were not, those scholars who adhere to the epistemological strategy of Milton Friedman would no doubt contend that a demonstration of the falsity of component propositions in no way reflects upon the soundness of the theory. By testing implications, rather than components, such a contention simply cannot arise. We now briefly consider the evidence presented in some standard historical works on British commercial diplomacy in the 19th century. There is a lack of consensus among hegemonic stability theorists about the timing of the end of British hegemony. Hence I focus on British efforts to secure European adherence to an open trading system, rather than on possible later efforts to maintain that system. Since hegemonic stability theory posits hegemon￾to-target influence as the mechanism for propagating an open trading system, the investigation centers on this process rather than on the origins of Britain's low tariff policy. (Whatever the origins of Britain's policy, the case for or against the theory clearly rests on whether the open trading system was propagated in the way the theory postulates.) In the period 1750-1815, Britain attempted to use the granting of pref￾erential access to the British home market as a bargaining chip; in turn, Britain frequently sought preferential access to other markets when nego￾tiating. This policy was officially ended by the Reciprocity of Duties Act of