The Theory of Groupthink Applied to Nanking

            During their occupation of the city of Nanking, Japanese forces perpetrated inconceivable acts of violence and disrespect towards human life. Our initial response to this occurrence is to question how people can commit such atrocities on fellow human beings. In attempting to obtain a firmer grasp of what occurred at Nanking, we must first look at the event from a sociological perspective. The decision-making process, when undertaken by large groups of people, often produces unexpected (and illogical) results.  The initial orders given to the Japanese soldiers to kill all prisoners were barbaric in and of themselves, but the soldiers went well beyond those orders. Ultimately, the soldiers at Nanking chose to mutilate, torture, and rape the inhabitants of the city. One syndrome which develops in aggregates of people that often results in such unexplainable decisions is groupthink.


            Groupthink is defined as ďA strong concurrence-seeking tendency that interferes with effective group decision makingĒ (Forsyth, 40).  The events at Nanking occurred within the context of an altered mode of thinking that essentially made the Japanese soldiers incapable of making rational decisions.  From the outset, the Japanese soldiers living in the occupied city of Nanking formed a deeply cohesive group.  Sociological research suggests that members of such unified groups lose the ability to realistically appraise a situation and devise alternative plans of action.  In an effort to maintain unity within the group, the Japanese based their decision-making process on reaching complete agreement, which in turn resulted in tragic errors of judgment which could have otherwise been avoided. In order to understand the concept of groupthink and how it relates to the events which occurred at Nanking, it is important to examine the symptoms and the causes of this decision-making disorder.

Symptoms of Groupthink

            There are eight identifiable symptoms that occur in groups in which there is the presence of groupthink.  The first of these symptoms is referred to as interpersonal pressure.  In group situations the pressure to reach a unanimous decision is intense, and there is a direct pressure to conform.  The interpersonal pressure to reach a consensus causes agreement to become more desirable than disagreement.  Non-conformity in groupthink situations is virtually intolerable.  In fact, aggressive efforts may be made in order to stifle the opinions of any members who may dissent.  The pressures to conform to the group override any criticisms members may have of the decisions being made by the group. 

            Another symptom of groupthink is self-censorship.  Self-censorship causes members of a group to refrain from confiding to other members their private doubts and uncertainties concerning the actions of their group.  When members of a group censor their own thoughts and opinions, the final resolutions made by the group may appear to be unanimous when in fact many of the members disagree with the group. 

            Mindguards also affect groupthink.  A mindguard is a member of the group who, in an attempt to preserve the central group idea, omits any information which may cause doubts to arise within the group.  A mindguard assumes the responsibility of sheltering the other members of the group from any ďcontroversialĒ information which may create a disruption in the overall group dynamic.  If a mindguard receives any negative outside information, he does not relate it to the group.  A mindguard also applies pressure to any dissenting members, ultimately forcing them into silence.  To this end, the mindguard may employ a variety of different strategies to persuade the dissenter to change his opinion.  One of these strategies would be to convince the dissenter that the group may disintegrate if all members are not in total agreement.  The goal of a mindguard is to prevent any questions regarding the groupís decisions from becoming apparent to the other group members.

            A fourth symptom of groupthink is the apparent unanimity of a group.  When members of a group censor their own dissension, the other group members observe what appears to be group unanimity.  Even if many members in a group disagree with the action the group is taking, they may not make their objections known to other members, instead assuming that all other group members are in acceptance of the situation. No single group member is willing to disrupt the clear consensus reached by the group, which in turn leads other group members to the erroneous conclusion that everyone agrees within the group.

            The illusion of invulnerability is another symptom of groupthink.  Members of a group in which no one voices their disagreement may have the perception that their group is performing well.  In essence, group members believe that their group as a whole could not possible perform sweeping errors in judgment. Members are extremely self-assured and confident in the groupís decision-making ability.  Over-confidence in the groupís decision-making powers leads members to form an illusion of invulnerability in which members believe they are invulnerable to any obstacle, allowing them to push aside clear and analytical thinking.

            The sixth symptom of groupthink is the illusion of morality, in which members participating in the group decision-making process tend to lose sight of their personal moral principles.  Rather, belief in the overall morality of the group overrides any individual sense of right and wrong.  Groups that make huge errors in judgment tend to formulate incorrect judgments about the groupís true intentions.

            Biased perceptions of the outgroup are another symptom of groupthink.  Members of a tightly cohesive group tend to perceive any non-group members as outsiders.  The resulting close-mindedness creates stereotyped images of the outsiders.  Ultimately, outsiders may often be perceived as dumb, evil, and/or weak.  Their abilities are discredited and underestimated.  More importantly, the devaluation of the outgroup results in a degree of dehumanization which allows the ingroup to justify the violence and inhumanity of their actions.

            Defective decision-making strategies also arise from groupthink.  More often than not, the decisions reached in groupthink situations are usually incorrect ones.  The poor decisions associated with groupthink situations are a result of defective decision-making strategies.  One common component of  a defective strategy is the groupís attachment to a limited set of alternatives which omit other, more acceptable possible courses of action from the discussion.  This results in a decision based on an incomplete review of the alternatives open to the group. 

            Another defective strategy employed in groupthink situations is the conscious omission of information which may reveal weaknesses in the plan.  Instead, group members focus only on information which supports their actions, creating an inaccurate appraisal of the situation and altering the perceptions of the group so that they lean more in favor of the currently-agreed upon course of action.  Defective decision-making strategies can ultimately induce the group to lose sight of the initial overall objectives, since the group fails to fully incorporate all of the relevant data.

Causes of Groupthink

            There are several main causes of groupthink. These include group cohesiveness, overall group isolation, group leadership, and decision-making stress.  High levels of cohesiveness decrease the amount of verbal dissension within a tight group, due to interpersonal pressure to conform.  This high level of cohesiveness also creates self-censorship and apparent unanimity within the group.  Normally, group dissension is necessary for good decision-making, because it introduce different perspectives to the decision-making process.  In the absence of this disagreement, alternative choices for action are never considered. 

            Another cause of groupthink is isolation. Often in group situations, it is important that the decisions being made or the actions being carried remain secret.  This requires that no outside opinions or thoughts be incorporated into the decision-making process.  Frequently, groups reach resolutions and carry them out without conferring with any outside sources.  One result of this extreme isolation is insulation from criticism.  This absence of criticism may lead to illusions of group invulnerability and morality.

            The leadership of a group can also lead to groupthink, since complete control over the group by the leader can cause an environment in which no one states their own opinions.  When extremely rigid leadership is implemented within a group (such as occurs in the military) group discussions are often tightly controlled.  Any dissenting opinions tend to be suppressed through intimidation or be simply not allowing the dissenter to voice his objections.  If a leader in a group situation makes his opinion clear at the outset of the discussions, group members will on many occasions refrain from expressing any disagreement out of respect for the leaderís authority. 

              Another cause of groupthink is decisional stress.  When a group is forced to make an important decision, each individual within the group often harbors a certain amount of insecurity.  Often without being aware, members of a group will attempt to reduce this decisional stress through any possible means.  Since this insecurity is lessened if the decision is made quickly and with little disagreement, the group can easily rationalize a decision because there of the minimal amount of dissension within the group.  The positive consequences of the groupís decision serve as the main focus, while there is a minimization of any negative outcomes.  Concentrating on minor details of group decisions or actions is a way in which the group can overlook larger issues that may need attention.  In high pressure group decision-making, attempts by members to reduce the stress associated with decision-making often results in groupthink.


Application of Groupthink to the Rape of Nanking

            It attempting to understand the events which culminated in the rape of Nanking, it is necessary to examine the mental decision-making which could have lead to such an unanticipated and inhumane outcome.         


            There were many symptoms of groupthink present in the overall environment at Nanking.  For instance, within military situations, interpersonal pressures to conform are intense.  Tolerance for nonconformity is virtually non-existent, and extreme tactics to bring dissenters into line are common-place. 

            Self-censorship was most likely another important symptom of the groupthink that occurred at Nanking.  Privately, many soldiers may have disagreed with what was occurring, but they chose to keep their doubts to themselves.  This self-censorship led to the appearance of unanimity among the soldiers. 

            Even though many Japanese soldiers may have inwardly objected to the events that were taking place, there was an apparent unanimity among the group.  The objections to these events never surfaced from the soldiers because of the overall pressure to conform.  If the ďnormĒ appeared to be the torture of the Chinese captives, this false sense of unanimity discouraged each individual soldier from going against the overall group dynamic. 

            Another symptom of groupthink common in military situations is an illusion of invulnerability.  Since the Japanese soldiers had conquered the entire city, their confidence in the group led them to believe that major errors were not possible, leading to view their decision-making process as infallible.

            The Japanese soldiers may also have experienced illusions which allowed them to warp their sense of morality.  Individual morals were lost in the overwhelming group desire to take total control of Nanking.  Justification for the atrocities that occurred was imbedded in the groupís desire for complete submission from the Chinese.  The Japanese soldiersí illusions of morality among their own countrymen outweighed any personal moral thought. 

            The biased perceptions of the Chinese were shared by the Japanese soldiers.  They did not view the people of Nanking as whole people.  To the Japanese soldiers, the Chinese were simply the enemy, and the enemy did not deserve to live.  A dehumanization occurred which resulted in the countless mutilations and rapes that occurred.

            Finally, defective decision-making strategies illustrates the occurrence of groupthink at Nanking.  Clearly, the decision to bury prisoners waist-high to allow dogs to attack the top half of their bodies was cruel and inhumane, as was the decision to allow soldiers to compete in decapitation contests.  Numerous people participated in arriving at these outrageous decisions.  These group members lost sight of their overall goal and became wrapped up in the individual issues surrounding the disposal of the prisoners of war.


            All four causal factors of groupthink were present during the Japanese occupation of Nanking, ultimately leading up to the numerous atrocities which occurred.  The Japanese soldiers that occupied Nanking were a cohesive group. With the shared experience encompassing the horrors of war, individuals within the group had formed strong bonds of friendship, leading to an overall sense of camaraderie.  This tight cohesiveness made it hard for any single group member to voice disapproval of the events taking place.  If any individuals did manage to verbally dissent with the actions of the other group members, they were likely to be ostracized.  This cohesiveness among the occupying soldiers in Nanking resulted in a continuation of the inhumane acts, since it appeared as though no one had any objections to the misdeeds.

            The group of Japanese soldiers was also isolated from the rest of society.  The officials who were control of the situation worked hard to ensure that the events which occurred within the boundaries of the city remained concealed. Few outsiders entered Nanking during the occupation, since the Japanese barred foreign diplomats and the press.  Although there were staged visits prepared for visitors, no outsiders ever saw what was truly happening.  This isolation created virtual isolation from any criticism which might have been leveled at the soldiersí actions.  This absence of any different perspectives of the abuses created the groupthink which occurred within this group of soldiers.

            The Japanese leadership at Nanking also contributed to the process of groupthink.  Due to the formality within the Japanese army, no officers solicited the troops for the individual opinions and concerns. Rather, the order to the troops was simply that all prisoners of war were to be executed.  In carrying out these orders, many soldiers may have simply taken the edict too far, while the pressure from the leadership to conform prevented any soldiers from dissenting.  In this sense, the strict leadership of the soldiers in Nanking resulted in the absence of dissension among the soldiers.

            The stress placed on the soldiers to make decisions involving the execution of thousands of prisoners was overwhelming.  Since the inhumane executions took place within the first eight weeks of the occupation, individual insecurities were minimized by group members performing their assigned task as quickly as possible.  This haste also reduced the amount of overall dissension, which in turn helped to reduce the stress placed on the soldiers.  The soldiers also rationalized their actions by focusing their attention on the overall outcome and goals of the war.  This attempt to reduce decision- making stress was a prime factor contributing to the presence of groupthink.


            The presence of groupthink can drastically alter the decision making capabilities of a group, often a preventing a group from arriving at rational decisions.  An analysis of the events which occurred during the Japanese occupation of Nanking during World War II shows many symptoms and causes of groupthink. While the inhumane nature of these events in many ways defies our understanding of human nature, the isolation and cohesiveness of the Japanese forces at Nanking can help in the explanation of this barbarity. Likewise, the cohesiveness combined with the strict leadership enforced the irrational decisions, effectively squelching any dissenting voices which might have sought to prevent the rape of Nanking from occurring. The presence of groupthink in the decision making processes of the soldiers is one explanation as to how events, as horrible as the ones that took place in Nanking, could have occurred.