Cognitive Biases — Groupthink

Michael Gearon
3 min readMay 9, 2020
Photo by Brooke Cagle on Unsplash

When we are in groups it can feel easier to follow the group and the collective decisions that the group make.

The idea of groupthink goes one step further to suggest that regardless of how irrational the decision is we would rather there be conformity in the group so if that decision is something we wouldn’t normally go with we may comprise that so peace remains in the group.

In groups we could be sacrificing individual creativity, thinking and uniqueness to avoid causing conflict and the preference to fit in. As well as it having impacts within the group it can also lead to consequences with those outside the group and dehumanizing their actions.

The 8 step checklist

The term groupthink was formed in 1972 by social psychologist Irving L. Janis, in which he created 8 different “sympyoms” that could indicate group think:

  1. Illusions of invulnerability lead members of the group to be overly optimistic and engage in risk-taking.
  2. Unquestioned beliefs lead members to ignore possible moral problems and ignore the consequences of individual and group actions.
  3. Rationalizing prevents members from reconsidering their beliefs and causes them to ignore warning signs.
  4. Stereotyping leads members of the in-group to ignore or even demonize out-group members who may oppose or challenge the group’s ideas.
  5. Self-censorship causes people who might have doubts to hide their fears or misgivings.
  6. “Mindguards” act as self-appointed censors to hide problematic information from the group.
  7. Illusions of unanimity lead members to believe that everyone is in agreement and feels the same way.
  8. Direct pressure to conform is often placed on members who pose questions, and those who question the group are often seen as disloyal or traitorous.

Research has shown that groupthink becomes stronger when the group members are very similar, increasing further when there is a powerful and charismatic leader in the group too. Groupthink can also happen when there is stress or where there is a moral dilemma, especially if the decision has to be rushed it can lead to poorer decision making and outcomes.

Examples of groupthink

There are two examples of this bias, one of which is the Bay of Pigs invasion in which President Kennedy made a decision to try and attempt to topple the communist government of Fidel Castro, which failed. The people around the President suported his deicsion to go ahead and kept their own concerns at bay. If groupthink didn’t happen then it could have led to a different decision.

The second example is the Challenger Space Shuttle diaster where the engineers of the space shuttle knew about faulty parts with the shuttle plenty of time before takeoff. Instead of reporting it they decided (as a group) to push ahead with the launch anyway to avoid negative press.

To reduce the effect of groupthink there are a few steps you can take. The most obvious steps is to keep group sizes as small as possible and let everyone in the group have time to express their own ideas or argue against ideas that have already been put forward.

More cognitive biases



Michael Gearon

Senior Interaction Designer and Co-Author to Tiny CSS Projects