David Levinson: Seasons' of A Man's Life In May of 1977, Daniel Levinson constructed a model of the season's of a mans life. His developmental theory consists of universal stages or phases that extends from the infancy state to the elderly state. Most development theories, such as Freud's psychosexual development theory or Piaget's cognitive development theory, end in the adolescent stage of life. Levinson's stage theory is important because it goes beyond most theories assuming that development continues throughout adult life. Levinson based his model on biographical interviews of 40 American men. These 40 men