The book contains a systematic presentation of the foundations of the theory of reflective games, built by the author. The purpose of this theory is to predict the individual choice of a subject who is part of a group and to investigate the possibilities of controlling that choice. The group, as a whole, may have its own interests. The connection of the interests of the group with the individual interests of the subjects is coordinated by the principle of the prohibition of selfishness: each subject, pursuing his personal goals, cannot harm the group as a whole. This principle is as important in reflexive game theory as the principle of guaranteed outcome in classical game theory.