The article analyzes sets used by subjects with different levels of the ability to act in the mind in perception of a communication partner. A study of students of a Moscow university discovered that cognitive egocentricity on a low level of the ability to act in the mind manifests itself in the dominance of the operational level of regulation of activity. That peculiarity reflects on the individual style of activity which is characterized by subjectivity in assessing other people as well as outcomes of one's own activity.