One of the most thought provoking philosophers in history was Socrates. Through the words of Plato his thoughts have been conveyed to generations since his time. One of his most engaging topics of contemplation was that of the immortality of the soul. Using his reasoning skills he formulated a vague, yet revolutionary theory on what the concept of a "soul" is and all that it entails. In Plato's Phaedo, Socrates argues that the soul is immortal and that we must rise above our physical nature in order to gain true knowledge.
In the Phaedo, Socrates friends suggest that the soul may perish. Socrates believes that the soul is immortal and if a person detaches himself from the physical pleasures of the world his soul may become free to follow the gods into Hades. However, if the soul has indulged in the physical pleasures it will be riveted to the body or it may not want to go with the gods to Hades and so this soul will remain here among the "living" and be thrust back into the physical world once the desire for the physical becomes strong enough.
Socrates friends mused over the probability of reincarnation of the soul from one body to another body. Cebes, one of Socrates" friends, argued that this is so because some of the acquired knowledge from past lives is subconsciously known when entering a new life. This idea of recollection gives us reason to believe in reincarnation, but it is not necessary for proving we have had other lives before our present ones. Socrates believes this and says that this is proof that the soul is immortal, if you have experienced recollection. Therefore, previous arguments for the soul's death with the body must be false, Socrates concludes.
One of the most important parts of Socrates" theory on the immortality of souls is that in order to leave the cycle of reincarnation of the soul into new bodies, you must separate yourself from the physical aspects in life, so that they won"t draw you back to this world.