There are numerous approaches to discovering a systematic theory of personality in order to answer some of the bothersome questions that have developed in psychology regarding this phenomenon. Personality theory must answer first what makes people behave alike, and also what makes people behave differently. The first question tries to find the conditions, factors, and variables that can account for the reactions the members of the human species show in common, and the second tries to explain the observed differences in the behavior of different individuals in response to the same situation. Another problem in personality theory is to explain what remains the same throughout the lifetime of the individual, what there is of personality that survives through time.
Personality theories can be grouped under a number of general headings according to historical and philosophical criteria, and there are also certain characteristics of personality theory that distinguish it from general behavior theory. Hall and Lindzey (1957) cite five such characteristics: 1) dissent from traditional academic theory; 2) concern with practical problems; 3) concern with causes of behavior; 4) treatment of the whole person; and 5) concern with the integration of diverse findings. They also note that those who founded personality theory were all practicing physicians whose daily practice required a rationale and a set of procedures for coping with the psychological problems presented by their patients. They feel that the concerns with personality were dictated by the demands of the medical practice faced each day.
Psychoanalysis is the general term for certain theories of personality, particularly those associated with Freud and his followers. Freud assumed that all men have the same set of instincts and that they concerned survival, sexuality, and death. All men have all these instincts in the core personality, and they exert a continual, general...