The Group

"..Irvin Janis, following George Orwell, has called the tendency for the attitudes of a tightly knit group to become extreme 'Groupthink'. According to him, the members may develop an illusion of invulnerability coupled with extreme optimism; they ignore inconvenient facts; their belief in their own morality may lead them to commit immoral actions as a means to an end; they hold stereotyped views of rival or enemy groups whom they regard as evil or weak; individual members attempt to silence dissent from others in the group; each member suppresses his own doubts in order to conform; there is an illusion of unanimity resulting from this supression; and finally, they protect other members by concealing information not in line with the group's views. Two further points are worth making. First, when a leader picks an advisory committee, he is unlikely to select either people who have very different views from himself or people who are more intelligent or more powerful in discussion than himself. The point cannot be proven, but to maintain their self-esteem leaders are likely to surround themselves by acolytes, thus exacerbating the tendencies already mentioned. Second, when a committee has a leader, the members will want to please him, particularly if he can influence their careers: this can be particularly pernicious, for the more the members agree with the leader, the more extreme his own attitudes are likely to become and hence the other members make even more extreme statements. It is a characteristic vicious circle.

Stuart Sutherland, Irrationality pg 46