Abstract

Political scientists working in the qualitative tradition claim to be using a method that they call process tracing. They claim that process tracing is a method of causal inference similar to that used by historians, a method that has a distinct logic from the statistical logic used by social scientists working in the quantitative tradition. But it’s unclear what this logic is. I suggest that there are two types of process tracing: (a) process tracing to test a ‘start-end’ hypothesis, and (b) process tracing as an end in itself. While the logic of this first type of process tracing is easy enough to uncover, the logic of this second type of process tracing is more mysterious. I make some tentative proposals. The upshot is that, although process tracing is indeed a distinctive method of causal inference, it has much more in common with quantitative/statistical inference than its advocates currently recognize.