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⁵ Private communication to the author.

⁶ New York Times, November 27, 1999, A1.

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¹⁴ Carr, , Socialism in One Country, 1924–1926 (New York: Macmillan, 1958–1964), 1:151.CrossRefGoogle Scholar

¹⁵ Lebow and Stein (fn. 11) review this argument and the new evidence (chap. 4).

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²⁶ The first of these experiments, involving alternative outcomes for the Cuban missile crisis, is described in Tetlock and Lebow (fn. 20).

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²⁸ Robyn M. Dawes, “Counterfactual Inferences as Instances of Statistical Inferences,” in Tetlock, and Belkin, (fn. 7), 301–8.Google Scholar Strictly speaking it does not follow that if x then y; therefore, if not-x, then not-y, because factors other than x may also cause y.

²⁹ Fearon, “Causes and Counterfactuals in Social Science: Exploring an Analogy between Cellular Automata and Historical Processes,” in Tetlock and Belkin (fn. 7).

³⁰ See, for example, George, Alexander L. and Smoke, Richard, Deterrence in American Foreign Policy: Theory and Practice (New York: Columbia University Press, 1974)Google Scholar; George, Alexander L. and Simmons, William E., eds., The Limits of Coercive Diplomacy (Boulder, Colo.: Westview, 1994)Google Scholar; Hopf, Ted, Peripheral Visions: Deterrence Theory and American Foreign Policy, 1965–1990 (Ann Arbor: University of Michigan Press, 1994)Google Scholar; Jervis, Robert and Snyder, Jack, eds., Dominoes and Bandwagons: Strategic Beliefs and Great Power Competition in the Eurasian Rimland (New York: Oxford University Press, 1991)Google Scholar; Risse-Kappen, Thomas, Cooperation among Democracies: The European Influence on U.S. Foreign Policy (Princeton: Princeton University Press, 1995).Google Scholar

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³² Cederman, “Rerunning History: Counterfactual Simulation in World Politics,” in Tetlock and Belkin (fn. 7).

³³ Fearon (fn. 29).

³⁴ George W. Breslauer discusses this literature in Breslauer, “Counterfactual Reasoning in Western Studies of Soviet Politics and Foreign Relations,” in Tetlock and Belkin (fn. 7).

³⁵ Mueller, John, Retreat from Doomsday: The Obsolescence of Major War (New York: Basic Books, 1989).Google Scholar And see the debate on this subject between Mueller, “The Essential Irrelevance of Nuclear Weapons: Stability in the Postwar World,” and Jervis, Robert, “The Political Effects of Nuclear Weapons: A Comment,” both in International Security 13 (Fall 1988).CrossRefGoogle Scholar

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⁴⁰ Tetlock, and Belkin, (fn. 23), 14.Google Scholar

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⁴² Newton reasoned that the energy reaching us from an individual star is E/∧2, where r is the distance of the star, and E is the average energy radiated by each star, and if the density (d) of stars in the universe is constant, the number of stars would be r∧3. The total energy produced by these stars would grow in a linear fashion with r, and rise to infinity in an infinite universe—neither we nor the earth would exist. Hence, the density of stars must decrease or the universe must be finite.

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⁴⁶ See fn. 35 for Mueller and the follow-up debate on nuclear weapons between Mueller and Jervis.

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⁶⁰ Dawes, “Counterfactual Inferences as Instances of Statistical Inferences,” in Tetlock and Belkin (fn. 7)

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⁶⁴ Elster (fn. 38); Kiser and Levi (fn. 61); and Tetlock and Belkin (fn. 23) also believe this is a reasonable standard for judging the plausibility of counterfactuals; Tetlock and Belkin acknowledge that “we should expect disagreement about what counts as well-established theory in world politics” (p. 27).

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⁷² Lebow (fn. 37).

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⁷⁹ Weber (fn. 48).

⁸⁰ Friedrich Engels suggested something similar. History was a “parallelogram of forces.” If one person shook his arms to move one corner of the parallelogram, it affected parts of the figure far away and far removed from intentions of the actor. Evans, Richard J., In Defense of History (New York: Norton, 1999), 118.Google Scholar