Pierre Janet

Pierre Janet (Paris, 1859 – Paris, 1947) was a French philosopher, psychologist and neurologist who ranks, with Wilhelm Wundt and William James, among the founders of modern psychology. His work focused on hysteria, anxiety, phobias, dissociation and traumatic memory, and he is remembered for bringing a careful clinical and experimental method to the study of mental disorders.

After studying at the Ecole Normale Supérieure and teaching in secondary schools in Châteauroux and Le Havre, he presented his thesis on psychological automatism in Paris in 1889. That same year Jean-Martin Charcot invited him to the Salpêtrière hospital, where he was put in charge of a laboratory of experimental psychology. There he completed his medical thesis, L'état mental des hystériques, in 1892, arguing that the symptoms of hysteria arose from psychological suggestion. He taught at the Sorbonne from 1898 and from 1902 held the chair of experimental and comparative psychology at the Collège de France, a post he kept until 1936. In 1904 he co-founded, with Georges Dumas, the Journal de psychologie normale et pathologique.

Janet held that many symptoms come from a splitting of consciousness, in which certain experiences become detached from the self and operate automatically. He also sketched a hierarchy of behaviour, from simple reflexes to complex social and rational activity, and understood neurosis as a failure to integrate these levels or a slide back toward earlier ones. He coined the terms "dissociation" and "subconscious", and his notion of the fixed idea remains one of his most debated contributions.

His relationship with Sigmund Freud was complicated. Freud initially acknowledged his debt, but after the priority dispute became public around 1913 he gave Janet less and less credit. Janet's influence nonetheless reached Carl Jung and Alfred Adler, and it has returned to prominence in contemporary trauma research.