The introspection illusion is a cognitive bias in which people wrongly think they have direct insight into the origins of their mental states, while treating others’ introspections as unreliable. In certain situations, this illusion leads people to make confident but false explanations of their own behavior (called “causal theories”) or inaccurate predictions of their future mental states.

The illusion has been examined in psychological experiments, and suggested as a basis for biases in how people compare themselves to others. These experiments have been interpreted as suggesting that, rather than offering direct access to the processes underlying mental states, introspection is a process of construction and inference, much as people indirectly infer others’ mental states from their behavior.

When people mistake unreliable introspection for genuine self-knowledge, the result can be an illusion of superiority over other people, for example when each person thinks they are less biased and less conformist than the rest of the group. Even when experimental subjects are provided with reports of other subjects’ introspections, in as detailed a form as possible, they still rate those other introspections as unreliable while treating their own as reliable. Although the hypothesis of an introspection illusion informs some psychological research, the existing evidence is arguably inadequate to decide how reliable introspection is in normal circumstances. Correction for the bias may be possible through education about the bias and its unconscious nature.

The phrase “introspection illusion” was coined by Emily Pronin. Pronin describes the illusion as having four components:

  1. People give a strong weighting to introspective evidence when assessing themselves.
  2. They do not give such a strong weight when assessing others.
  3. People disregard their own behavior when assessing themselves (but not others).
  4. Own introspections are more highly weighted than others. It is not just that people lack access to each other’s introspections: they regard only their own as reliable.