Belief, when it is not simply traditional, is a product of several factors: desire, evidence, and iteration. When either the desire or the evidence is nil, there will be no belief; when there is no outside assertion, belief will only arise in exceptional characters, such as founders of religions, scientific discoverers, and lunatics. To produce a mass belief, of the sort that is socially important, all three elements must exist in some degree.
Source: Power, 1938.
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