Leon Festinger
SchoolCognitive Dissonance Theory
Lived1919 – 1989
FromUnited States
Cognitive Dissonance Theory

Leon Festinger

The mind seeks its own consistency

The American social psychologist who explained why our beliefs bend to fit our actions.

When belief and action collide, it is often the belief that gives way.
— Leon Festinger

Who they were

Leon Festinger noticed that people feel a real discomfort when their beliefs and behavior clash, and that they will quietly rewrite their thinking to make the tension go away. His theory of cognitive dissonance reshaped how psychologists understand persuasion, decision-making, and self-justification. With a famous field study of a doomsday group whose prophecy failed, he showed that disconfirmed believers often grow more fervent, not less. He also charted how we measure ourselves against others through social comparison, leaving a lasting mark on the field.

Famous books

What they left on the shelf

Their big idea

Cognitive Dissonance

Leon Festinger showed that holding two clashing beliefs, or acting against what we believe, creates an uncomfortable tension we are driven to resolve. Often we quietly change our minds to fit what we have already done, smoothing the story we tell ourselves.

Questions in their spirit

What they’d ask you

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All questions

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Festinger — What they’d ask you

Psipas asks you one small, honest question at a time — and builds the picture from your answers.