Summary

1. A theory provides a framework of general principles to guide research and to explain observations. Each of the five major developmental theories—psychoanalytic, behaviorist, cognitive, sociocultural, and universal—interprets human development from a distinct perspective, together interpreting human experience and behavior.
2. Theories are neither true nor false. They are not facts; they suggest hypotheses to be tested. Good theories are practical: They aid inquiry, interpretation, and daily life.
3. A norm is a usual standard of behavior. Norms are not theories, although they may result from theories if a theory suggests that a certain behavior is proper. Norms are not necessarily good or bad, although sometimes differences from the norm are falsely considered deficits.

4. Psychoanalytic theory emphasizes that human actions and thoughts originate from unconscious impulses and childhood conflicts. Freud theorized that sexual urges arise during three stages of childhood development—oral, anal, and phallic—and continue, after latency, in the genital stage.
5. Erikson described psychosocial, not psychosexual, stages. He described eight successive stages of development, each involving a crisis as people mature within their context. Societies, cultures, and family members shape each person’s development.
6. All psychoanalytic theories stress the legacy of childhood. Conflicts associated with children’s erotic impulses have a lasting impact on adult personality, according to Freud. Erikson thought that the resolution of each crisis affects adult development.
7. Behaviorists, or learning theorists, believe that scientists should study observable and measurable behavior. Behaviorism emphasizes conditioning—a lifelong learning process, in which an association between one stimulus and another (classical conditioning) or the consequences of reinforcement and punishment (operant conditioning) guide behavior.
8. Social learning theory recognizes that people learn by observing others. Children are particularly susceptible to social learning, but all humans are affected by other people.
9. Cognitive theorists believe that thoughts and beliefs powerfully affect attitudes, actions, and perceptions. Piaget proposed four age-related periods of cognition, propelled by an active search for cognitive equilibrium. Information processing focuses on each aspect of cognitive input, processing, and output.

10. Sociocultural theory explains human development in terms of the guidance, support, and structure provided by knowledgeable members of the society through culture and mentoring. Vygotsky described how learning occurs through social interactions, when mentors guide learners through their zone of proximal development.
11. The universal perspective focuses on the shared impulses and common needs of all humanity. One universal theory is humanism. Maslow believed that humans have five basic needs, which he arranged in sequence beginning with survival and ending with self-actualization. Rogers believed that each person merits respect and appreciation, with unconditional positive regard.
12. Evolutionary theory contends that contemporary humans inherit genetic tendencies that have fostered survival and reproduction of the human species for tens of thousands of years. Many hypotheses arising from this theory are intriguing but controversial.

13. Psychoanalytic, behavioral, cognitive, sociocultural, and universal theories have each aided our understanding of human development, yet no single theory describes the full complexity and diversity of human experience. Most developmentalists are eclectic, drawing upon many theories.