The concept of “mirror” and the action of “mirroring” are used in psychology and psychotherapy, in various schools or orientations, from the cognitivist ones to those psychoanalytic. From Wallon to Lacan, the study of the mirror is either the theoretical expression of the moment when the child discovers his own body or of the discovery of another, his parent, when he looks into the mirror. Jacques Lacan described the mirror stage as formative for the function of the „Ego”. The mirror stage is not a simple phenomenon occurring in the process of the child growth; it illustrates the conflict of the dual relationship. The Self is created through the identification with its own image.