Given that mathematical objects do not exist, on the mathematical fictionalist perspective, the problem of how we can obtain knowledge of them simply vanishes. But another problem emerges instead: what is it that distinguishes a mathematician (who knows a lot about mathematics) and a non-mathematician (who does not have such knowledge)? The difference here (according to Field 1984) is not about having or lacking mathematical knowledge, but rather it is about logical knowledge: of knowing which mathematical theorems follow from certain mathematical principles, and which do not. The epistemological problem is then solved—as long as the mathematical fictionalist provides an epistemology for logic.