Tractable Falsifiability

We propose to strengthen Popper's notion of falsifiability by adding the requirement that when an observation is inconsistent with a theory, there must be a "short proof" of this inconsistency. We model the concept of a short proof using tools from computational complexity, and provide some examples of economic theories that are falsifiable in the usual sense but not with this additional requirement. We consider several variants of the denition of "short proof" and several assumptions about the difficulty of computation, and study their different implications on the falsifiability of theories. JEL Classification: B400