False-consensus effect

The false-consensus effect is the tendency to overestimate how widely other people share one’s beliefs, preferences, or behaviors. It can make personal views seem more widely accepted than they are.

Social projection: The tendency to expect other people to think, feel, or behave as oneself does. Projecting personal views onto others is a direct route to overestimating their prevalence.
Lee Ross: An American social psychologist known for research on attribution, judgment, and social inference. Ross and colleagues named and demonstrated the false-consensus effect in 1977.
Eat at Joe’s: A hypothetical choice in which participants considered wearing a sandwich board reading “Eat at Joe’s.” Ross, Greene, and House used this choice to compare participants’ decisions with their estimates of others’ decisions.
False uniqueness effect: The tendency to underestimate how common one’s desirable abilities or behaviors are among others. It reverses the direction of the false-consensus effect for traits people value.
Group polarization: The tendency for group discussion to shift members toward a more extreme version of their initial position. Perceived agreement can reinforce confidence and help a group move toward more extreme views.
Availability heuristic: A mental shortcut that judges likelihood or frequency by how easily examples come to mind. One’s own opinions are especially accessible, making them seem more widespread.
Andrew Ward: A social psychologist who coauthored the 1977 study introducing the false-consensus effect. Ward helped establish the effect through experiments on choices and estimates of others’ choices.
False-consensus effect in elections: The tendency to overestimate how many people share one’s own political preferences or voting choices. Political preferences make the effect visible in estimates of how common a candidate’s support is.
Fundamental attribution error: The tendency to overemphasize personal traits and underestimate situational causes when explaining others’ behavior. It concerns explanations of behavior, whereas false consensus concerns estimates of how widely views or behaviors are shared.
Pluralistic decision-making: Collective decision-making in which participants form judgments while considering other members’ views. Misjudging how widely a position is shared can distort collective choices.

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