The fanatic cannot be weaned away from his cause by an appeal to his reason or moral sense. He fears compromise and cannot be persuaded to qualify the certitude and righteousness of his holy cause. But he finds no difficulty in swinging suddenly and wildly from one holy cause to another. He cannot be convinced but only converted, His passionate attachment is more vital than the quality of the cause to which he is attached.

Eric Hoffer (1902-1983) American writer, philosopher, longshoreman

True Believer: Thoughts on the Nature of Mass Movements, Part 3, ch. 13, § 61 (1951)
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