Now Socrates is in a position to construct the final argument for immortality. The soul is like the triad. It is necessarily related to Life, because it can only bring life into the body it enters. And so it does not admit its opposite, Death. This makes the soul deathless, and what is deathless cannot be destroyed.1. The soul can only bring life to the body into which it enters
2. So, the soul does not admit the opposite of life
3. The opposite of life is death
4. So, the soul never admits death
5. So, the soul is deathless
6. What is deathless is indestructible
7. So, the soul is indestructible
This argument meets the "cloak" objection raised by Cebes. It is not very satisfactory, though. Suppose we grant the first step, does the second follow? The fact that the soul brings life to the body does not mean that it is itself necessarily living. It might be that, so to speak, death can be brought to it, though it cannot bring death to something. And the argument also depends on making Death a form opposite to Life. It is plausible to suppose that death is nothing positive, like the Even or even Injustice (as found in acts of murder). Death may well be simply the cessation of life.
