Early psychological thought

Many cultures throughout history have speculated on the nature of the mind, heart, soul, spirit, brain, etc. For instance, in Ancient Egypt, the Edwin Smith Papyrus contains an early description of the brain, and some speculations on its functions (described in a medical/surgical context). Though other medical documents of ancient times were full of incantations and applications meant to turn away disease-causing demons and other superstition, the Edwin Smith Papyrus gives remedies to almost 50 conditions and only two contain incantations to ward off evil.

Ancient Greek philosophers, from Thales (fl. 550 BC) through even to the Roman period, developed an elaborate theory of what they termed the psuchẽ (psyche) (from which the first half of "psychology" is derived), as well as other "psychological" terms – nous, thumos, logistikon, etc.The most influential of these are the accounts of Plato (especially in the Republic), Pythagoras and of Aristotle (esp. Peri Psyches, better known under its Latin title, De Anima).

Plato's tripartite theory of the soul, Chariot Allegory and concepts such as eros defined the subsequent Western Philosophy views of the psyche and anticipated modern psychological proposals, such as Freud's id, ego and super-ego and libido; to the point that "in 1920, Freud decided to present Plato as the precursor of his own theory, as part of a strategy directed to define the scientific and cultural collocation of psychoanalysis". Hellenistic philosophers (viz., the Stoics and Epicurians) diverged from the Classical Greek tradition in several important ways, especially in their concern with questions of the physiological basis of the mind.The Roman physician Galen addressed these issues most elaborately and influentially of all. The Greek tradition influenced some Christian and Islamic thought on the topic.

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