L.M. Alvarez-Calderon - lecture delivered during Second International Conference on Positive Disintegration Mental Health and Development (27-30 December 1972). 1. The problem of -development and the growing apprehension and assimilation of reality. 2. The importance of consciousness and its effeects in the field of sociology. 3. The theory of positive disintegration as a frame of reference that allows the study of human development and mental growth.