Contemporary organismic and bio-social accounts of human behavior consider physical and psychological concepts as alternative or complementary linguistic descriptions of the same subject matter. The notion of complementarity is an important part of the organismic physicalistic synthesis which replaces the old duels between mechanism and vitalism, between physiology and psychology. The concept of complementarity comes from Bohr's solution for the difficulty of reconciling classical mechanics with quantum mechanics. He suggested that they are parallel and complementary rather than contradictory ways of looking at the universe. The continuity of the energy transfer according to the electromagnetic theory and the atomicity of light effects are “complementary aspects of one reality in the sense that each expresses an important feature of the phenomena of light, which, although irreconcilable from a mechanical point of view, can never be in direct contradiction, since a closer analysis of one or the other feature in mechanical terms would demand mutually exclusive experimental arrangements” (3).