Pierre Janet (1859-1947) is widely known today as a proponent of dissociation, traumatic memory, and subconscious phenomena. In the first part of this article, I review Janet's early papers leading up to "Psychological Automatism (L'automatisme psychologique)" and show how he led the formation of a new psychology. Janet's major influences were his uncle, the philosopher Paul Janet; the neurologist J. M. Charcot; his predecessor at the Collège de France, Théodule Ribot; a fellow psychical researcher, the physiologist Charles Richet; and Henri Bergson who was a collaborator in the formation of a new philosophy of mind. Each was a pioneer in his own intellectual field, and under their influence, Janet pioneered the formation of a psychology unique to France. In particular, he examined the theories that led to the discovery of the "the law of dissociation" and traumatic memory in 1886, as well as the subsequent arguments that led to narrative and temporal theories. He taught at the Collège de France for 30 years after being appointed professor in 1902 and wrote numerous books and papers. His works were clearly oriented toward social psychology, which he called the "psychology of conduct (psychologie des conduites)". Janet's theory was influenced by the collective developmental psychology of Baldwin, Guillaume, and others that was centered on imitation, and by his constant incorporation of changing findings of related sciences of his time, however, he continued to have an interest in the concept of hysteria. Although Janet's influence was said to have waned after World War I, he developed a "bottom-up type" (as Hacking notes) psycho-philosophy. Janet's later works, which considered the whole picture of the hierarchical structure of tendencies, show a very exciting development as he introduced the theory of language, which revolves around 'command' and 'obedience'; the theory of social sentiments, which attempts to understand the process from the four basic sentiments to beliefs; and the theory of pre-linguistic intelligence, including 'unity (unité)' and 'individuality (individualité)', as exemplified by "the conduct of basket of apples (conduite du panier de pommes)". Janet's works give us a critical, deconstructive perspective that is open to the sciences and lead to psychology and clinical psychiatry.
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