In thus concluding his argument for the immortal justice meted out to the just and the unjust, Plato is forced to argue the authority of myth because he cannot demonstrate his argument logically; there exists no demonstrable proof. Plato's myth here embraces the doctrine of reincarnation.
Thus it is that, even after death, for Plato justice is rewarded and injustice is punished. We should note carefully that each soul is granted the life he chooses before he is reincarnated. Plato held quite firmly to the idea that men could choose to be evil or to be good, and he did not hold to any doctrine of predestination of a life lived evilly or well. A bad man chooses to be bad.
But how can this be, when we know that a life lived unjustly is a life of misery? Why would a man choose unhappiness? Plato's answer to that is that choices are many times made from ignorance (amathia). The unjust man would realize the woe he is bringing upon himself if only he would listen to his reason and try to learn something. And so we see, truly, that the unexamined life is not worth living.
