Tertullian, A Treatise on the Soul 31

If the living come from the dead, they must come one-to-one. That means each individual soul ought to return to its own individual body. But if two, three, or five souls are crammed back into a single womb, the living are no longer coming from the dead, because the one-to-one rule is broken. This whole theory forces the primordial pattern into a singleton mold, even though right now multiple souls are born from one mother. Then there is the age problem: souls die at every stage of life, so why do they all come back as infants? Everyone starts from infancy. What sense does it make for an old man to die and return as a baby? If the soul shrinks outward with age going in reverse, it should have been even more fitting for it to come back more advanced a thousand years later. At minimum, it should have retrieved the exact age it left, returning as a contemporary of its own death.

Even granting that the same souls recycle, they ought to carry their old character traits, pursuits, and passions with them, even if their bodies change. Without those markers, they would be declared the same arbitrarily, lacking the very evidence that would prove identity. You ask how I know this does not happen secretly, since the sheer length of time destroys the ability to recognize returning strangers? I know it does not happen, and Exhibit A is your own star witness: Pythagoras and Euphorbus. Euphorbus was a military, warlike soul, well attested by the fame of his dedicated shields. Pythagoras, by contrast, was so sedentary and unwarlike that he fled the wars of Greece for the quiet of Italy, devoting himself to geometry, astrology, and music, utterly alien to Euphorbus' pursuits and passions. Then there is Pyrrhus, who made a practice of tricking fish; Pythagoras would not even eat them, abstaining from animals. Aethalides and Hermotimus dove into common fare like beans; Pythagoras forbade his disciples even to walk through bean fields. How can the same souls be recovered when they fail to match in character, in training, or in diet?

Right now, out of the vast population of Greece, only four souls are claimed to have recycled. But why stop at Greece? If metempsychosis and transmigration happen daily across every nation, every age, every rank, and both sexes, why does only Pythagoras recognize his past selves, and not me? If this is a philosophers' privilege, and a Greek one at that, as if Scythians and Indians do not philosophize, why do Epicurus, Chrysippus, Zeno, and even Plato himself recall nothing? We might have believed Plato was Nestor reincarnated, given the honey of his eloquence.