Socrates, the father of philosophers, explained his belief in the reality of reincarnation by saying: "If nature, which decreed death for every living thing, had simultaneously decreed that it should never return to life again, then annihilation would be the fate of all things, and nothing would remain alive continuously, as we see from the evidence of constant renewal."

After him came Plato, who found in the philosophy of transmigration a basis for his Philosophy of Forms—or what is called "God’s Thoughts." For the forms, in the past before their embodiment, lived in the realm of universal meanings and perceived them; then they settled into bodies to gain knowledge of the world of matter and particulars through the physical senses.

He also said: "The soul is simple and the form is simple; thus they are of one kind." Since the soul lives on, it remembers previous lives, and there is no fundamental difference in life before existence and after it. The connection between life and death is very similar to the connection between sleep and wakefulness; just as the transition occurs from sleep to wakefulness and vice versa, so too is life.

And death; thus, the transition is always from opposite to opposite, a matter from which there is no escape. If there were no transition from death to life, everything in existence would end in nothingness.

Plato followed Pythagoras, just as Plotinus followed them both later on, in terms of stating and believing in reincarnation across all living beings,