Hippolytus of Rome, The Refutation of All Heresies I.4: Empedocles; His Twofold Cause; Tenet of Transmigration

But Empedocles, born after these, advanced likewise many statements respecting the nature of demons, to the effect that, being very numerous, they pass their time in managing earthly concerns. This person affirmed the originating principle of the universe to be discord and friendship, and that the intelligible fire of the monad is the Deity, and that all things consist of fire, and will be resolved into fire; with which opinion the Stoics likewise almost agree, expecting a conflagration. But most of all does he concur with the tenet of transition of souls from body to body, expressing himself thus:—

“For surely both youth and maid I was,

And shrub, and bird, and fish, from ocean stray’d.”

This (philosopher) maintained the transmutation of all souls into any description of animal. For Pythagoras, the instructor of these (sages), asserted that himself had been Euphorbus, who served in the expedition against Ilium, alleging that he recognised his shield. The foregoing are the tenets of Empedocles.