What limits are placed on realist theory by the logic of the social that inheres in classical realism's basic assumptions about international politics? When combined with the relationship between realism and reflexivity discussed in Chapter 6, this logic constrains realism from confidently predicting outcomes. This proposition may at first seem absurd, given the claims of several strands of contemporary realism specifically to be scientifically predictive. But the core argument in this chapter is that these strands not only fail to fulfill claims of some contemporary realist theorists to be both predictive and prescriptive, but that too much focus on being predictive, on being scientific, also undermines the core insight of classical realism.

This core insight, as phrased by Hans Morgenthau, is that we must see the world as it is, rather than as we want it to be. “Political realism believes that politics, like society in general, is governed by objective laws.” This observation seems, at first glance, to support an argument that realism is about scientific prediction. But embedded in this core insight is the claim that the realist world, the world as it is, is not that neatly predictable. “The first lesson the student of international politics must learn and never forget is that the complexities of international affairs make simple solutions and trustworthy prophesies impossible. Here the scholar and the charlatan part company.