Social work s history as a profession has been marked by historical shifts from an emphasis on individual therapy to social reform, and visa versa. In the 80s and 90s, social work s human behavior knowledge base has expanded and the content has moved away from any single-theory approach that emphasizes individual behavior and staged development. A third impact comes from experimental psychology and learning theory - this provides concern for carefully controlled empirical research, a better understanding of the nature of theory construction, and a more detailed appreciation of how behavior is modified. A fourth determinant is represented by the psychometric tradition with its focus upon measurement and study of individual differences. While personality theories differ, especially in their explanations of early stages of development, there are certain modal qualities or central tendencies that tie these theories to one another.
Personality theories are typically functional in their orientation.
They focus on issues that are of critical importance in the development, adaptation, and survival of the organism - like the major motivations that explain human behavior. Personality theorists have customarily assigned a crucial role to the motivational process. These lead to the collection or observation of relevant empirical relations not yet observed. The acceptance or rejection of a theory is based on its utility, not by its truth or falsity . Utility refers to verifiability and comprehensives.