Henry Alexander Murray (1893–1988) formulated Personology, a term he coined to denote the study of human lives as a whole and the factors that influence their course. Rejecting rigid, atomistic trait psychologies, Murray posited that personality is rooted in brain processes (viscerogenic and psychogenic states) and must be understood in terms of longitudinal development and the ongoing interaction between internal drives and environmental situations.
- Viscerogenic Needs: Primary, biological needs necessary for physiological survival, such as the need for food, water, air, sex, and harm avoidance.
- Psychogenic Needs: Secondary needs derived from biological roots, operating mostly at an unconscious level, such as the need for achievement ($n$ Ach), affiliation ($n$ Aff), autonomy ($n$ Aut), dominance ($n$ Dom), and succorance ($n$ Suc).
- Press: Environmental forces, objects, or conditions that facilitate or obstruct an individual's goal pursuit. Alpha press refers to objective, real-world reality, while beta press represents the subjective, perceived interpretation of that reality by the individual.
- The Thema and Unity-thema: A thema is a molar behavioral unit consisting of a combination of a need (or fusion of needs) and a corresponding press. A unity-thema is a dominant, recurring pattern of related themas originating from early childhood experiences that shapes the entire life course of the person.