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"You are never dedicated to something you have complete confidence in. No one is fanatically shouting that the sun is going to rise tomorrow. They know it is going to rise tomorrow. When people are fanatically dedicated to political or religious faiths, or any other kinds of dogmas or goals, its always because these dogmas or goals are in doubt." (Robert M. Pirsig)

"A fanatic is a man who consciously over compensates a secret doubt." (Aldous Huxley)

"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts." (Bertrand Russell)