Final answer:
Abraham Maslow is credited as the father of the human relations movement, known for creating the hierarchy of needs theory that emphasizes self-actualization and the positive potential of human beings.
Step-by-step explanation:
The father of the human relations movement is generally considered to be Abraham Maslow. Maslow was instrumental in establishing humanistic psychology as the "third force" in psychology, alongside psychoanalysis and behaviorism. He's well-known for creating Maslow's hierarchy of needs, which is a theory in psychology proposing that there are five levels of human needs that motivate our behavior. The highest level of this hierarchy is the need for self-actualization, or reaching our fullest potential. Maslow emphasized the positive potential of human beings and was critical of the reductionist approach of behaviorism and the pessimistic determinism of psychoanalysis.