Knowledge is like money: the more he gets, the more he craves.

Appetite grows with supply. Learning something reveals the shape of what you did not know, so each answer produces several new questions, and the sense of having enough recedes as fast as you approach it. That is why the well read often feel more ignorant than beginners do.

Taken well, this is one of the better cravings to have and it needs no cure. It does need direction, or it turns into collecting: endless input, no use. Pick one question you actually want answered and follow it until you can explain the answer to somebody else, then let the next one come.