Donald Green and Ian Shapiro discover a curious gulf between the prest
ige of rational choice approaches and the dearth of solid empirical fi
ndings. But we can understand neither the prestige of rational choice
theory nor its pathologies unless we see it as a variant of the equili
brium analysis found in physics, economics, and biology. Only such a g
lobal perspective on rational choice cheery will reveal its core assum
ptions and the likely shape of its future in political science. In thi
s light, the growing dominance of rational choice theory in political
science is all but inevitable and its pathologies are all but inescapa
ble.