There are a variety of ways of thinking about personality. The most prominent current approaches are the trait or temperament approaches, which usually have a strong biological component, and the motivational approaches, which follow in the footsteps of behavioristic and social cognitive approaches. The other approaches discussed in this SparkNote--the psychodynamic and humanistic-existential approaches--are not widely practiced today, but have strongly influenced the history of the field and the kinds of questions that are now being asked. Each of these approaches is briefly summarized below; more detailed descriptions can be found in each Topic.

The paradigm example of a psychodynamic approach to personality is the approach that started the whole modern field: psychoanalysis. Sigmund Freud, a Viennese neurologist, devised his system of psychology from clinical interviews with his patients, most of whom were women diagnosed with hysteria. He focused on basic instincts, specifically the sexual and aggressive drives, and the id, ego, and superego, mental structures that he believed interacted to produce human behavior. Freud influenced a great deal of later research on personality. Some of his basic assumptions--that our behavior is mostly determined by the unconscious, that early life events are important determinants of life-long behavior, and that humans are naturally violent and selfish--continue to undergird some modern theories of personality. Another important personality researcher in the psychodynamic tradition is Erik Erikson, who focused on the social drives that influence behavior over the life-span.

The humanistic and existential approaches came into being in the 1950s and 1960s, and have mostly faded since. They are important, however, because they represented a break from the dominant paradigms of the time: psychoanalysis and behaviorism (see below). Instead of focusing on the unconscious, unpleasant determinants of behavior postulated by psychoanalysis, or the environmental factors emphasized by behaviorism, humanistic and existential personality researchers focused on human tendencies towards self-improvement, self- actualization, and autonomy. Important humanistic theorists include ##Abraham Maslow and Carl Rogers#{psychology/personality/humanistic/section2} #. One of the more influential existential theorists was Rollo May.

Behaviorism was one of the dominant approaches to psychology in America for the middle half of the twentieth century. Although it was largely based on animal behavior, and tended to focus on basic behaviors, it was also extended to deal with human personality. Behaviorists like B. F. Skinner argued that human behavior is determined by learned environmental contingencies of reward and punishment, not by internal structures such as the "self" or the id, ego, and instincts described by psychoanalysis. Later researchers such as Albert Bandura rejected the radical behaviorist claim that internal structures were irrelevant, but they maintained behaviorism's emphasis on behavior and environmentally-influenced learning.

Trait theory is a relatively unified set of postulates about the main dimensions along which human personalities differ. Trait theory got its start in the work of Gordon Allport and others in the 1940s and 1950s, who used a statistical technique called factor analysis to determine the minimum number of independent factors--groups of descriptive words--that could capture most of the variance in the ways people describe each other and themselves. Current trait theory postulates that there are approximately five such groups of descriptors: "openness," "conscientiousness," "extroversion," "agreeableness," and "neuroticism," with extroversion and neuroticism being the most important, accounting for the majority of the variance. Trait theorists often assume that such traits have biological components, but they are rarely specific about what such components might consist of. Jerome Kagan has offered a description of temperaments that complements the trait theoretic approach and is explicitly based on inherited biological differences.