About the Theory
According to Rotter's theory, most behavior is learned from around us - from other people and from our situations. Behavior can be conditioned internally or externally, with a general goal of maximizing rewards or minimizing/avoiding punishments. The condition works on expediencies or expectations, altering how much we expect a given thing to go a given way, and make decisions accordingly. The theory considers both what has happened to the person and how the person perceives any given situation for a more complete picture.
To understand an individual's present behavior, the past events in that person's life should be considered. Rather than digging into the deep and buried past as some do, though, Rotter believes more recent events can be used. An example from the book explained that poor grades in high school and poor SAT scores are sufficient evidence to expect an individual to fail in college. Just as the past can be used to create expectations, the present can change how the past is viewed; as new experiences and knowledge come, feelings about past events are updated to reflect the new feelings.