If your work is becoming uninteresting, so are you. Work is an inanimate thing and can be made lively and interesting only by injecting yourself into it. Your job is only as big as you are.
-- George C. Hubbs
What seems to us as bitter trials are often blessings in disguise.
-- Oscar Wilde
When your views on the world and your intellect are being challenged and you begin to feel uncomfortable because of a contradiction you've detected that is threatening your current model of the world or some aspect of it, pay attention. You are about to learn something. This discomfort and intellectual conflict is when learning is taking place.