Habits that are actually signs you're smarter than you think

They criticize themselves

We tend to think that intelligent people are confident—why wouldn't they be, when they're so smart? But research suggests that might not be the case. In a landmark 1999 studyfrom Cornell University, scientists found that incompetent people couldn't recognize their own incompetence, which led to inflated self-assessments. This has become known as the Dunning-Kruger effect. "For poor performers to recognize their ineptitude would require them to possess the very expertise they lack," study author David Dunning, PhD, recently wrote in the Pacific Standard.