A set of concepts and propositions that describe, organize, and explain a set of observations. Must be able to be tested eg. Nature / nurture some say children are a result of their biology. Children are the result or nature and nurture. Conflict of individual"s instinct and societal norms for behaviour. Id part of you that wants what it wants - instinctual. Superego part a person that understands right or wrong - holds us in check. Some people say the joker is the grown up version of pure id. Stages propose shifts in focus on parts of body. Anal (1 3 years) development of ego, some control over themselves. Latency (6 -11 years) sports, school, kids continue to develop an ego. Viewed children as more active in development than freud. More emphasis on social and cultural influences on development. Contributions idea of unconscious motivation often uses hypnosis focus on later consequences of early experiences.