Proselytizing is more a passionate search for something not yet found than a desire to bestow upon the world something we already have. It is a search for a final and irrefutable demonstration that our absolute truth is indeed the one and only truth. The proselytizing fanatic strengthens his own faith by converting others.

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

True Believer: Thoughts on the Nature of Mass Movements, Part 3, ch. 14, § 88 (1951)
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