psychology

The word 'psychology' combines Greek 'psychē' (ψυχή, breath, spirit, soul, mind) with 'logos' (λόγος‌​‌​‌​‌​‍​‌​‍​‍​‍​‍​‍​‌​‍​‌​‌​‍​‍​‌​‍​‍​‌​‌​‍​‌​‍​‌​‍​‌​‌​‍​‌​‍, word, discourse, study, reason) to produce 'study of the soul' or 'study of the mind.' The compound did not exist in classical Greek; it was coined in Modern Latin as 'psychologia' by humanist scholars in the sixteenth century.

The earliest known uses of 'psychologia' appear in Latin treatises from the 1570s and 1580s, particularly those associated with the German scholar Philipp Melanchthon and his followers. The word was created on the model of other Greek-derived compound nouns for branches of learning — theologia, physiologia, and so on. It entered English in the mid-seventeenth century.

Greek 'psychē' has a rich semantic history. Its earliest meaning was 'breath' — the breath of life that distinguishes a living body from a dead one. From 'breath' it extended to 'soul' — the animating principle of a living being — and from 'soul' to 'mind' in the sense of the seat of thought, feeling, and consciousness. The PIE root *bhes- (to breathe) connects 'psyche' to the fundamental observation that life is breath and death is its cessation.

In Greek mythology, Psyche was a mortal princess whose beauty rivaled Aphrodite's. The myth of Psyche and Eros, most fully told in Apuleius' 'The Golden Ass' (2nd century CE), narrates Psyche's journey through trials and tribulations to ultimate union with the god of love — widely interpreted as an allegory of the soul's journey toward the divine. In Greek art, Psyche was commonly depicted with butterfly wings, the butterfly symbolizing the soul's emergence and transformation.

Psychology as a named field existed for centuries as a branch of philosophy — the philosophical study of the soul and its faculties. The transformation of psychology into an experimental science is usually dated to 1879, when Wilhelm Wundt established the first psychology laboratory at the University of Leipzig. Wundt's approach — applying the methods of natural science to the study of conscious experience — established psychology as a discipline distinct from philosophy.

The twentieth century saw psychology fragment into competing schools: Freud's psychoanalysis (the study of unconscious drives), behaviourism (the study of observable behaviour, rejecting the study of consciousness), humanistic psychology (emphasizing subjective experience and personal growth), and cognitive psychology (the study of mental processes like memory, perception, and reasoning). Each school claimed the name 'psychology' while defining its subject matter differently — a disagreement rooted in the ambiguity of 'psychē' itself, which can mean 'soul,' 'mind,' 'consciousness,' or 'behaviour' depending on one's theoretical commitments.

The 'psych-' prefix produces a large English word family. 'Psychiatry' (soul-healing, from Greek 'iatros,' healer) treats mental disorders medically. 'Psychoanalysis' (soul-analysis) is Freud's method of investigating unconscious mental processes. 'Psychedelic' (soul-manifesting, from Greek 'dēlos,' visible) was coined in 1957 for substances that alter perception and consciousness. 'Psychotic' (of the soul/mind) describes a break with reality. 'Psychosomatic' (soul-body) describes physical symptoms with psychological causes.