The "soul," as it first appeared in Greek thought, had a religious though not a Christian origin. It seems, so far as Greece was concerned, to have originated in the teaching of the Pythagoreans, who believed in transmigration, and aimed at an ultimate salvation which was to consist of liberation from the bondage to matter which the soul must suffer so long as it is attached to a body. The Pythagoreans influenced Plato, and Plato influenced the Fathers of the Church ; in this way the doctrine of the soul as something distinct from the body became part of Christian doctrine.
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