Phaedo: Part 2

The two challenges

Perhaps: 1. The soul is not a substance, a harmony in the body 2. The soul, while a substance, is not immortal


An interlude.

Harmony Challenge

The Affinity Argument

  1. The soul is to the body as the divine is to the mortal
  2. The body is surprisingly durable
  3. The immortal is more durable than the mortal

Therefore the soul will outlast the body

The Challenge

It seems like the harmony is the lyre as the divine is to the mortal.

But the harmony doesn’t outlast the lyre.


  1. From Recollection

  2. From Disanalogies

The Coat Challenge

Even if the soul preexists the body, that’s no proof that it will outlast the body (or outlast a series of bodies)

The Reply

Critique of Greek Natural Science.

Basic structure: Identify Material Principles, Efficient Principles of things.

Plato’s Criticisms

  1. This makes us forget common sense
  2. This does not explain substantial change, or everyday properties of things
  3. This does not give the correct explanation of goal-directed activity

Alternative: The Theory of Forms

Explain traits and change in terms of forms.

Does this do any better on 1-3?

Formal Explanation

Some traits of things are to be explained by “specialized” forms or form-like things.

The person is sick because they have a fever.

The person is alive because they have a soul.

Essential features

A fever can’t be healthy—because feverishness (formally) explains sickness.

A soul can’t be dead—because having a soul (formally) explains being alive.

The concluding myth

Beautiful Mansions by a river for the virtuous

Tartarus for the vicious

I do not mean to affirm that the description which I have given of the soul and her mansions is exactly true—a man of sense ought hardly to say that. But I do say that, inasmuch as the soul is shown to be immortal, [one] may venture to think, not improperly or unworthily, that something of this kind is true.