Phaedo.Now I propose to determine what things, without being the opposites of something, nevertheless refuse to admit it, as the number three, though it is not the opposite of the idea of even, nevertheless refuses to admit it, but always brings forward its opposite against it, and as the number two brings forward the opposite of the odd and fire that of cold, and so forth, for there are plenty of examples. Now see if you accept this statement: not only will opposites not admit their opposites, but nothing which brings an opposite to that which it approaches will ever admit in itself the oppositeness of that which is brought. Now let me refresh your memory; for there is no harm in repetition. The number five will not admit the idea of the even, nor will ten, the double of five, admit the idea of the odd. Now ten is not itself an opposite, and yet it will not admit the idea of the odd; and so one-and-a-half and other mixed fractions and one-third and other simple fractions reject the idea of the whole. Do you go with me and agree to this?Yes, I agree entirely, he said, and am with you.Then, said Socrates, please begin again at the beginning. And do not answer my questions in their own words, but do as I do. I give an answer beyond that safe answer which I spoke of at first, now that I see another safe reply deduced from what has just been said. If you ask me what causes anything in which it is to be hot, I will not give you that safe but stupid answer and say that it is heat, but I can now give a more refined answer, that it is fire; and if you ask, what causes the body in which it is to be ill, I shall not say illness, but fever; and if you ask what causes a number in which it is to be odd, I shall not say oddness, but the number one, and so forth. Do you understand sufficiently what I mean?Quite sufficiently, he replied.Now answer, said he. What causes the body in which it is to be alive?The soul, he replied. Is this always the case?Yes, said he, of course.Then if the soul takes possession of anything it always brings life to it?Certainly, he said.Is there anything that is the opposite of life?Yes, said he.What?Death.Now the soul, as we have agreed before, will never admit the opposite of that which it brings with it.Decidedly not, said Cebes.Then what do we now call that which does not admit the idea of the even?Uneven, said he.And those which do not admit justice and music? Unjust, he replied, and unmusical.Well then what do we call that which does not admit death?Deathless or immortal, he said.And the soul does not admit death?No.Then the soul is immortal.Yes.Very well, said he. Shall we say then that this is proved?Yes, and very satisfactorily, Socrates.

Phaedo.Well then, Cebes, said he, if the odd were necessarily imperishable, would not the number three be imperishable?Of course.And if that which is without heat were imperishable, would not snow go away whole and unmelted whenever heat was brought in conflict with snow? For it could not have been destroyed, nor could it have remained and admitted the heat.That is very true, he replied.In the same way, I think, if that which is without cold were imperishable, whenever anything cold approached fire, it would never perish or be quenched, but would go away unharmed.Necessarily, he said. And must not the same be said of that which is immortal? If the immortal is also imperishable, it is impossible for the soul to perish when death comes against it. For, as our argument has shown, it will not admit death and will not be dead, just as the number three, we said, will not be even, and the odd will not be even, and as fire, and the heat in the fire, will not be cold. But, one might say, why is it not possible that the odd does not become even when the even comes against it (we agreed to that), but perishes, and the even takes its place? Now we cannot silence him who raises this question by saying that it does not perish, for the odd is not imperishable. If that were conceded to us, we could easily silence him by saying that when the even approaches, the odd and the number three go away; and we could make the corresponding reply about fire and heat and the rest, could we not?Certainly.And so, too, in the case of the immortal; if it is conceded that the immortal is imperishable, the soul would be imperishable as well as immortal, but if not, further argument is needed.But, he said, it is not needed, so far as that is concerned; for surely nothing would escape destruction, if the immortal, which is everlasting, is perishable.All, I think, said Socrates, would agree that God and the Principle of life, and anything else that is immortal, can never perish.All men would, certainly, said he, and still more, I fancy, the Gods.Since, then, the immortal is also indestructible, would not the soul, if it is immortal, be also imperishable?Necessarily.Then when death comes to a man, his mortal part, it seems, dies, but the immortal part goes away unharmed and undestroyed, withdrawing from death.So it seems.