The Dunning–Kruger effect is a cognitive bias in which unskilled individuals suffer from illusory superiority, mistakenly rating their ability much higher than average. This bias is attributed to a metacognitive inability of the unskilled to recognize their mistakes. Actual competence may weaken self-confidence, as competent individuals may falsely assume that others have an equivalent understanding. Kruger and Dunning conclude, "the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others". ...

An opsimath can refer to a person who begins, or continues, to study or learn late in life. The word is derived from the Greek ὀψέ (opse), meaning 'late' and μανθάνω (manthano), meaning 'learn'. Opsimathy was once frowned upon, used as a put down with implications of laziness, and considered less effective by educators than early learning. The emergence of "opsimath clubs" has demonstrated that opsimathy has shed much of this negative connotation, and that this approach may, in fact, be desirable. Notable opsimaths include Sir Henry Rawlinson, the fictitious character Sir Henry Rawlinson...