In the field of psychology, the Dunning–Kruger effect is a cognitive bias in which people mistakenly assess their cognitive ability as greater than it is. It is related to the cognitive bias of illusory superiority and comes from the inability of people to recognize their lack of ability. Without the self-awareness of metacognition, people cannot objectively evaluate their competence or incompetence.
The more a person knows, the more obvious it is to him how insufficient that knowledge is. This law might work the other way around: the less a person knows, the more confident he is of his knowledge and immensity. This illusion of confidence is known as the "Dunning-Krueger effect" and describes the cognitive distortion of inflated self-esteem. The difference is that truly competent people, unlike incompetent people, are open to criticism and can adjust their self-esteem based on appropriate feedback from difference-between.net