原版英文："The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts."
- Burson, Katherine A.; Larrick, Richard P.; Klayman, Joshua (2006). "Skilled or unskilled, but still unaware of it: How perceptions of difficulty drive miscalibration in relative comparisons". Journal of Personality and Social Psychology. American Psychological Association. 90 (1): 60–77.
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