Clark Hull's Drive Theory

Hull’s Drive Theory
Clark Hull can be regarded as the first dominant motivational theorist. He formulated his general theory of motivation and related it with experimental psychology. He drew on ideas from a number of other thinkers including Charles Darwin, Ivan Pavlov, and John. B. Watson and Edward L. Thorndike. He based his theory around the concept of homeostasis, the idea that the body actively works to maintain a certain state of balance or equilibrium. Based on this idea, Hull (1943) suggested that all motivation arises as a result of the biological needs. In his theory, Hull used the term drive to refer to the state of tension or arousal caused by biological or physiological needs. Thirst, hunger and the need for warmth are all examples

Drive is a pooled energy source. This was examined by varying two needs simultaneously and showing that they both activated the same response.
While Hull 's theory was popular during the middle part of the 20th-century, it began to fall out of favor due to a number of reasons. Because of his emphasis on quantifying his variables in such a narrowly defined way, his theory lacks generalizability. However, his emphasis on rigorous experimental techniques and scientific methods did have an important influence in the field of psychology.
One of the biggest problems with Hull 's drive reduction theory is that it does not account for how secondary reinforcements reduce drives. Unlike primary drives such as hunger and thirst, secondary reinforcements do nothing to directly reduce physiological and biological needs. While Hull 's theory has largely fallen out of favor in psychology, it is still worthwhile to understand the effect it had on other psychologists of the time and how it helped contribute to later research in psychology.
Lewin’s Field Theory
Kurt Lewin’s field theory flourished between 1935 and 1960. His emphasis on coalescing psychology with the philosophy of science resulted in an extensive number of pragmatic studies performed in the realms of child development, motivation and social behavior, particularly having to do with experiments and research on children’s

He decoded Gestalt philosophy into social experience comprising people who should be considered as wholes instead of being formed of separate entities. A person is shown as a whole system consisting of subsystems that are somewhat distinct yet are still capable of interacting and mingling with each other. He was one of the first psychologists to suggest that the growth of an individual was the product of the interaction between inborn predispositions (nature) and life experiences (nurture). This conception was presented by Lewin in the form of a mathematical equation known as Lewin’s Equation for behavior, stating that behavior is determined by both the person (P) and the environment