Stupid people tend to overestimate their competence, while smart people tend to sell themselves short. As Shakespeare put it in "As You Like It": "The fool doth think he is wise, but the wise man knows himself to be a fool."
That conventional wisdom is backed up by a Cornell University study conducted by David Dunning and Justin Kruger. The phenomenon is now known as the Dunning-Kruger effect.
So, if you're not too sure about your own intellect, it actually might be an indication that you're pretty intelligent — thoughtful enough to realize your limitations, at least.
Here are some subtle signs that you are considerably smarter than you think:
Drake Baer and Chelsea Harvey contributed to a previous version of this article.
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