 As we have seen, in Proofs and Refutations Lakatos had already joked that “actual history is frequently a caricature of its rational reconstructions”. The use of the plural—“reconstructions”—is important. There is more than one way of rationally reconstructing history, and how you do it depends upon what you count as rational and what not—it depends, in short, in your theory of rationality. There is not one “rational history”—as Hegel may have thought—but several competing ones. And, in a remarkable dialectical turn, Lakatos proposed that one can evaluate competing theories of rationality by asking how well they enable one to reconstruct the history of science (whether it be mathematics or empirical science). The thought is that if your philosophy of science, or theory of scientific rationality, deems most of “great science” irrational, then something is wrong with it. Contrariwise, the more of the history of “great science” your theory of rationality deems rational, the better that theory is.