People virtually never encounter someone without expectations of how he or she will behave.  And these expectations are notoriously powerful, guiding every aspect of the person perception process.  Beliefs or naïve theories guide more than the pre-computed expectancies that observers bring with them to the interpersonal encounter, however. They also guide the post-computed expectancies (counterfactual norms) that observers generate during the encounter.

 I will discuss a recent line of research that has explored the impact of post-computed or counterfactual thoughts evoked by a target’s behavior on one of the most central aspect of the person perception process: trait inference.  We contend that observers’ impressions of actors reflect not only what actors do, but also what they can easily be imagined doing.  For example, we propose that the inference that a person is dishonest does not require that the person be observed acting dishonestly; it is sufficient that the person be observed in a situation that evokes images of another situation in which he or she most likely would have acted dishonestly.