In the 1950s, three prominent psychologists, Abraham Maslow, Carl Rogers, and Rollo May, pioneered humanism as the new psychological approach to understanding personality theory and development.
As the leader behind humanistic thinking, Maslow posited that there is a drive for self-actualization (the realization of a person's fullest potential) after the attainment of basic human needs. Maslow viewed self-actualizing people are embodying several key characteristics: self-awareness and -acceptance; the capacity to form close friendships that are not clingy or dependent; spontaneity; sense of humor; the capacity to see work as an enjoyable and fulfilling pursuit; the capacity to have emotionally/spiritually rewarding experiences.
Drawing on the work of Freud and Maslow, Carl Rogers advocated the person-centered theory based on clinical case studies. Rogers considered the self-concept the salient feature of personality because it encompasses all feelings, beliefs and thoughts people display towards themselves. Furthermore, Rogers asserted that people are cognizant of these self-concepts. However, he acknowledged that often, self-concepts are not indicative of reality ("incongruence"), as when a person considers himself a model of integrity and honesty but frequently lies to his spouse. In contrast, "congruence" occurs when there is a reliable match between a self-concept and reality.
Unlike Maslow and Rogers, Rollo May introduced a strain of existential psychology within humanistic theory. May posited that people frequently shirk responsibility and avoid decision-making because of feelings of apathy and emptiness; these emotional disorders prompt people to disconnect from the surrounding world, from others and from themselves. Consequently, May considered the objective of psychotherapy to help people become more human, rather than 'cure' them. This way, psychotherapy would empower people to make effective decision and assume proper responsibility for their choices and actions. May viewed people as experiencing four stages of development: Innocence (pre-ego, doing only what one must do to fulfill one's needs), Rebellion (formation of ego by rebelling against authority), Ordinary (typical adult ego in which one often chooses conformity over responsibility), and Creative (authentic adult who accepts of responsibilities of free will with courage).