Abraham Harold Maslow (April 1, 1908 – June 8, 1970) was a psychologist best known for creating a theory of a hierarchy of needs moving from basic survival needs to ones of self-actualization. These needs are:
Physiological needs: basic physical needs necessary for staying alive. Example: food.
Safety needs: Need for physical and emotional security. Example: the property rights in the Magna Carta.
Love and belonging needs: These include personal relationships and group membership. Examples: marriage, joining a fraternity
Esteem needs: Both self-esteem and feeling appreciated by others. Example: good grades, Nobel prize, etc.
Self-actualization needs: Realizing one's full potential. Example: Bill Gates, having made a fortune, is now using his talents and money to help the sick and poor across the world. Similarly, ex-President Jimmy Carter, having reached the summit of power as President of the U.S. has devoted himself to the cause of the poor (building houses with his own hands for the poor as part of Habitat for Humanity, for example). For Maslow, the ideal is to take care of all the other needs so that one can focus on self-actualization.