Humanistic psychology theory suits people who see the positive side of humanity and believe in free will. This theory clearly contrasts with Freud's theory of biological determinism. Another significant strength is that humanistic psychology theory is compatible with other schools of thought. Maslow's Hierarchy is also applicable to other topics, such as finance, economics, or even in history or criminology. Humanist psychology, also coined "positive psychology", is criticized for its lack of empirical validation and therefore its lack of usefulness in treating specific problems. It may also fail to help or diagnose people who have severe mental disorders. Humanistic psychologists believe that every person has a strong desire to realize their full potential, to reach a level of "self-actualization". The main point of that new movement, that reached its peak in 1960s, was to emphasize the positive potential of human beings. Maslow positioned his work as a vital complement to that of Freud: