In Sophocles’ play Oedipus the King, a monster called the Sphinx was killing travelers on the road to Thebes who could not answer its riddle:  “What creature walks on four legs in the morning, two legs at noon, and three in the evening?”  Finally, the hero of the play, Oedipus, came along and correctly solved...Read More

Swiss philosopher Jean Piaget conceived of four cognitive stages of human development.  They are as follows: Birth to Age Two – The Sensori-Motor Stage:   infants develop their thinking processes solely through the body; in the course of moving their arms, legs, and torsos around, infants make things happen accidentally, and want to make them happen...Read More

Founder of psychoanalysis Sigmund Freud created a psychosexual model of human development based upon the erogenous zones of the body.  He believed that as these zones matured neurologically, they activated the emotional world of the child (largely resident in the unconscious), and in the course of doing so, created the basis for later emotional health...Read More

Psychologist Lawrence Kohlberg created a theory of moral development (or more properly, “moral reasoning”) based upon Jean Piaget’s stages of cognition.  There are three basic levels:  preconventional, conventional, and postconventional, and two stages within each level.  The six stages are as follows: Level 1 (Preconventional) 1. Obedience and Punishment Orientation – at this stage of...Read More

According to the ancient Romans, there are five stages of human development: 0-15 years – Pueritia – early childhood and latent period of early school years 15-25 – Adulescentia – puberty and adolescence 25-40 – Luventus – first adulthood 40-55 – Virilitas – second adulthood 55+ – Senectus – old age For more about the...Read More