The eight symptoms of groupthink include an illusion of invulnerability or of the inability to be wrong, the collective rationalization of the group’s decisions, an unquestioned belief in the morality of the group and its choices, stereotyping of the relevant opponents or out-group members, and the presence of “mindguards” who act as barriers to alternative or negative information, as well as self-censorship and an illusion of unanimity.
