The goal of psychology today is to understand people by considering both individual factors, z7z as how societal beliefs shape how we behave toward those other people. The principles of psychological science are cumulative: knowledge accumulates based on systematic study of questions raised by what is already known, relies on empirical evidence and builds on previous discoveries in a dynamic way. The mind is adaptive: the brain has evolved to solve survival problems and adapt to environments. S culture beliefs, values, rules and customs that exist within a group of people who share a common language and environment and that are transmitted through learning from one generation to the next: solving adaptive problems. S evolutionary theory solutions to these adaptive problems are built into the brain and therefore require no special training :2:ll z2 . Psychological science crosses levels of analysis: sociallculture and interpersonal behaviour, biologicallbrain systems, neurochemistry, genetics.