Metempsychosis is a theory of the soul derived from the teachings of the original tri-guy, Pythagoras, who definitely stole his ideas from the Indian concept of reincarnation. In metempsychosis, the soul is immortal and passes through cycles of incarnation in birth and release from the body at death. The behavior of the individual during a particular life can determine the form the soul takes in the next life. In the Phaedrus, Plato develops this theory of the immortal soul, arguing that after the death of body the soul passes through the realm of the Ideas, which is why we can possess particular kinds of knowledge, such as the consciousness of virtue and perfection, through the process of anamnesis or "recollection."