Worse still, we humans are the last to notice our own limited nature. In seven words, Shakespeare sums up a good portion of the findings of modern psychology: “most ignorant of what he’s most assured.” A recurring discovery of social and cognitive psychology is that human beings are absurdly overconfident in their own knowledge, wisdom, and rectitude. Everyone thinks that he or she is in the right, and that the people they disagree with are stupid, stubborn, and ignorant. People reliably overestimate their own knowledge, and misjudge their own accuracy at making predictions. A common theme of both Shakespeare and modern social psychology is the human species’ overconfidence.