In 1938, the American psychologist Henry Murray developed a system of needs as part of his theory of personality, which he named personology. Murray argued that everyone had a set of universal basic needs, with individual differences among these needs leading to the uniqueness of personality through varying dispositional tendencies for each need; in other words, a specific need is more important to some people than to others.
In his theory, Murray argues that needs and presses (another component of the theory) acted together to create an internal state of disequilibrium; the individual is then driven to engage in some sort of behavior to reduce the tension. Murray believed that the study of personality should look at the entire person over the course of their lifespan – that people needed to be analysed in terms of complex interactions and whole systems rather than individual parts – and an individual's behaviors, needs and their levels, etc. are all part of that understanding. Murray also argued that there was a biological (specifically, a neurological) basis for personality and behavior.[1][2]