Abraham Maslow

American psychologist who developed the hierarchy of needs — a motivational theory proposing that human needs form a pyramid from physiological to self-actualization — and founded humanistic psychology.

Hierarchy of needs: physiological → safety → love/belonging → esteem → self-actualization. Self-actualization: the highest human need — the realization of one's full potential. Peak experiences: rare moments of transcendence, insight, and bliss that point toward self-actualization. Co-founded the humanistic psychology movement and later transpersonal psychology.