by Irving Janis

Symptoms. In my studies of high-level governmental decision-makers, both civilian and military, I have found eight main symptoms of groupthink.

1.    INVULNERABILITY. Most or all of the members of the in-group share an illusion of invulnerability that provides for them some degree of reassurance about obvious dangers and leads them to become over-optimistic and willing to take extraordinary risks. It also causes them to fail to respond to clear warnings of danger.


2.    RATIONALE. Victims of groupthink ignore warnings: they also collectively construct rationalizations in order to discount warnings and other forms of negative feedback that, taken seriously, might lead the group members to reconsider their assumptions each time they recommit themselves to past decisions. James C. Thompson, Jr., a Harvard historian who spent five years as an observing participant in both the State Department and the White House, tells us that the policy-makers avoided critical discussion of their prior decisions and continually invented new rationalizations so that they could sincerely recommit themselves to defeating the North Vietnamese.

3.    MORALITY. Victims of groupthink believe unquestionably in the inherent morality of their in-group. This belief inclines the members to ignore the ethical and moral consequences of their decisions. Evidence that this symptom is at work usually is of a negative kind - the things that are left unsaid in group meetings.


4.    STEREOTYPES. Victims of groupthink hold stereotypes views of the leaders of enemy groups: they are so evil that genuine attempts at negotiating differences with them are unwarranted, or they are too stupid or too weak to deal effectively with whatever attempts the in-group makes to defeat their purposes, no matter how risky the attempts are.

5.    PRESSURE. Victims of groupthink apply direct pressure to any individual who momentarily expresses doubt about any of the group's shared illusions or who questions the validity of the arguments supporting a policy alternative favored by the majority. This gambit reinforces the concurrence-seeking norm that loyal members are expected to maintain.

6.    SELF-CENSORSHIP. Victims of groupthink avoid deviating from what appears to be group consensus; they keep silent about their misgivings and even minimize the importance of their doubts.


7.    UNANIMITY. Victims of groupthink share an illusion of unanimity within the group concerning almost all judgments expressed by members who speak in favor of the majority view. This symptom results partly from the preceding one, whose affects are augmented by the false assumption that any individual who remains silent during any part of the discussion is in full accord with what the others are saying. When a group of persons who respect each others' opinions arrives at a unanimous view, each member is likely to feel that the belief must be true. This reliance on consensual validation within the group tends to replace individual critical thinking and reality testing, unless there are clear-cut disagreements among the members. To avoid such an unpleasant state, the members often become inclined, without quite realizing it, to prevent latent disagreements from surfacing when they are about to initiate a risky course of action. The group leaders and the members support each other in playing up the areas of convergence in their thinking, at the expense of fully exploring divergences that might reveal unsettled issues.

8.    MINDGUARDS. Victims of groupthink sometimes appoint themselves as mindguards to protect the leader and fellow member from adverse information that might break the complacency they shared about the effectiveness and morality of past decisions.


Products. When a group of executives frequently have most or all of these symptoms, a detailed study of their deliberations is likely to reveal a number of immediate consequences. These consequences are, in effect, products of poor decision making practices because they lead to inadequate solutions to the problems under discussion.

        First, the group limits its discussions to a few alternative courses of action (often only two) without an initial survey of all the alternatives that might be worthy of consideration.

        Second, the group fails to reexamine the course of action initially preferred by the majority after they learn the risks and drawbacks they had not considered originally.

        Third, the members spend little or no time discussing whether there are nonobvious gains they may have overlooked or ways of reducing the seemingly prohibitive costs that made rejected alternatives appear undesirable to them.

        Fourth, members make little or no attempt to obtain information from experts within their own organizations who might be able to supply more precise estimates of potential losses and gains.

        Fifth, members show positive interest in facts and opinions that support their preferred policy; they tend to ignore facts and opinions that do not.

        Sixth, members spend little time deliberating about how the chosen policy might be hindered by bureaucratic inertia, sabotaged by political opponents, or temporarily derailed by common accidents. Consequently, they fail to work out contingency plans to cope with foreseeable setbacks that could endanger the overall success of their chosen course.


Support. The search for explanation of why groupthink occurs has led me through a quagmire of complicated theoretical issues in the murky area of human motivation. My belief, based on recent social psychological research, is that we can best understand the various symptoms of groupthink as a mutual effort among the group members to maintain self-esteem and emotional equanimity by providing social support to each other, especially at times when they share responsibility for making vital decisions.