Franz Brentano

Franz Brentano was an Austrian philosopher and psychologist who revived the medieval concept of intentionality — the "aboutness" of mental states — as the defining feature of consciousness. His work directly influenced Husserl, Freud, and much of twentieth-century European philosophy.

Brentano's Psychology from an Empirical Standpoint distinguished mental from physical phenomena by the criterion of intentional inexistence: every mental act is directed toward an object. His empirical psychology, his theory of correct emotion (Richtige Gefühl) as the basis of ethics, and his classification of mental acts set the agenda for phenomenology.