A good definition of Groupthink at Disinfopedia.

Groupthink is "a concept that was identified by Irving Janis ("a forefather in the study of group dynamics") [in 1972] that refers to faulty decision-making in a group. Groups experiencing groupthink do not consider all alternatives and they desire unanimity at the expense of quality decisions."[1] (http://www.abacon.com/commstudies/groups/groupthink.html)[2] (http://www.groupthinkfilm.com/)

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