through Plato's arguments for the immortality of the soul.

And last time I spent a fair bit of time working through

objections to, not quite the last argument

we're going to look at, but the penultimate argument,

in which Plato tries to argue for the simplicity of the soul.

The set of connected ideas, you'll recall,

were these: that Plato wants to suggest that in order to be

destroyed you've got to have parts;

to destroy something is to basically take its parts apart.

If he could only convince us that the soul was simple,

it would follow that it was indestructible and,

hence, immortal. He asks, what's our evidence

for some things being indestructible?

What kinds of things are simple? Well, these are--he then goes

on to claim--invisible things, things that don't change.

After all, changing is a matter of the rearrangement of the

parts. And so, if something can

change, it can't be simple. Maybe it could be destroyed.

But if we could become convinced that the soul was not

composite, if it was something that couldn't change,

then it would simple. Perhaps then it would

indestructible. And then he goes on to suggest

that the invisibility of the soul is evidence for it's being

changeless, and hence simple, and hence indestructible.

So that's the argument we worked through last time.

And I spent a fair bit of time suggesting that if you pin down

precisely what Plato means by invisible, the argument doesn't

actually go through. Before leaving that argument,

there are a couple of extra remarks I want to make about it.

First, we probably shouldn't have been so quick to want to

buy into the suggestion that the soul is changeless.

After all, if you think about it, it seems that at least on

the face of it the soul does indeed change.

On one day you believe, for example,

that it's hot; on another day you believe that

it's cold. On one day you believe that so

and so is a nice person; on the next day you believe

that so and so is a mean person. You desire to learn the piano,

the next day you give up on that desire.

Your beliefs, your goals, your intentions,

your desires--these things are all constantly changing.

And so, at least on the face of it, it looks as though we might

well want to say the soul--if we do believe there are souls--the

soul is changing as well, in terms of what thoughts and

beliefs it's housing. So we should have been

skeptical in the first place of any argument that said,

based on the invisibility of the soul, we can conclude that

it's changeless. It doesn't seem to be in fact

changeless. Furthermore,

we should be, or at least we might well be,

skeptical of the claim that the soul is simple.

Indeed, Plato himself, in other dialogues,

argues against the simplicity of the soul.

Now, that doesn't mean he's right in the other dialogues,

but at least suggests that we shouldn't be so ready to assume

that sort of position is correct.

In The Republic, famously, Plato goes on to

argue that the soul has at least three different parts.

There's a rational part that's in charge of reasoning;

there's a spirited part that's sort of like the will;

there's a part that has to do with appetite,

desires for food, drink, sex, what have you.

Plato elsewhere argues the soul is not simple at all.

So perhaps it shouldn't shock us that the argument he's

sketching here for the simplicity of the soul based on

the changeless, invisible nature of the

soul--perhaps it shouldn't shock us that that argument doesn't

succeed after all. Finally, although I gave Plato,

previously, the assumption that if only we could establish the

simplicity of the soul, it would follow that soul was

indestructible--after all, you couldn't break a soul by

tearing its pieces apart if it didn't have pieces,

if it didn't have parts--nonetheless,

I just want to register the thought that it's not actually

obvious that simples can't be destroyed.

Well, they clearly can't be destroyed by the particular

method of destruction that involves taking them apart.

If they don't have parts, you can't take them apart.

But for all that, it still seems conceptually

possible for a simple to be destroyed in the following

sense: it goes out of existence. After all, where did the

simples come from in the first place?

Well, at least from a logical point of view,

it seems as though there's no difficulty in imagining that at

one point a given simple didn't exist and then at the next point

it popped into existence. Well, how did that happen?

Maybe God said--God says at the beginning of Genesis,

"Let there be light." So maybe He says,

"Let there be simples." At a given moment they weren't

there; the next moment they were.

Well, after a while maybe God says, "Let the simples no longer

exist." Given moment there they were;

the next moment, they no longer exist.

Seems as though that idea makes sense, and so even if we agreed

that the soul was simple, even if we granted everything

in Plato's argument up to this point and said,

"the soul really is simple," it still wouldn't follow that it's

immortal. We'd still have to worry about

the possibility that the simple soul might simply pop out of

existence at a given point, perhaps the very point when the

body gets destroyed. So I'm inclined to think that

this most recent argument of Plato's--the argument from

simplicity--no, that's not successful either.

Before leaving that argument, there's one other piece

of business I want to discuss. This is a footnote that I put

aside, a point that I put aside previously.

You'll recall that we were worried about--The objection got

raised the right way to think about the soul is like the

harmony of a harp. And this was originally offered

as a counterexample to the thought that invisible things

couldn't be destroyed. But harmony could be destroyed.

It was invisible, so invisible things could be

destroyed. But I noticed,

I mentioned that, look, whether or not this is a

problem for the argument, it's an interesting suggestion

in its own right. Because the suggestion that the

mind is to the body, the soul is to the body,

like harmony is to an instrument with strings,

seems to me to be an early attempt to describe something

like the physicalist conception of the mind.

Just as harmony is something that gets produced by a

well-tuned instrument, the soul or the mind is

something that gets produced by a well-tuned body.

Now Plato's got some objections to the suggestion that we should

think of the mind as the harmony of the body.

And so I want to take just a moment and talk about those

objections because, of course, if they were

compelling objections that might well give us reason to doubt the

physicalist view. Whether or not Plato's

arguments for the immortality of the soul work,

he might still have some good arguments against the

physicalist conception. But in thinking about these

objections, it's important to bear in mind that it's only

meant--the harmony analogy is only meant--as just that,

as an analogy. Right?

The claim isn't, or at least it shouldn't be,

understood as saying literally, "the mind is harmony."

It's rather, the mind is like

harmony; it's the sort of thing to the

body like harmony is to a harp, something that can be produced

by a well-functioning, well-tuned physical object.

A well-tuned instrument can produce melody and harmony.

A well-tuned, properly functioning body can

produce mental activity. That's the suggestion.

And so even if it turns out that there are some ways in

which the mind isn't exactly like harmony,

it doesn't show us that the physicalist view is wrong.

Well, so let's quickly look at what Plato's arguments were.

First--this is, I think, an interesting

argument--Plato says, harmony clearly cannot exist

before the existence of the harp itself.

Right? The melodiousness of the harp

can't exist prior to the physical construction of the

harp. And if mind were the sort of

thing that was produced by the proper functioning of the

physical body, then pretty obviously the mind

could not exist prior to the creation of the physical body.

However, Plato has already argued earlier in the dialogue

that the soul does exist prior to the existence of the body.

That's the argument from recollection.

If the soul exists prior to the body, it can't be like harmony;

physicalism has clearly got to be false.

But I said that I didn't find the argument--I tried to explain

why I didn't find the argument from recollection persuasive.

I certainly do want to agree that if we became convinced that

the soul did exist prior to the existence of the body,

we would certainly want to agree that the soul is not like

harmony. But I don't think the argument

from recollection succeeds.

Plato's second objection is to point out that harmony can vary.

We talk about the melodiousness of the harp.

Well, it could be harmonious in a variety of different ways and,

indeed, to different degrees.

Something--an instrument--could be more or less harmonious.

What it's playing can be in greater or lesser harmony.

But it doesn't seem as though souls come in degrees.

You've got a soul or you don't have a soul.

That's the argument, that's the objection.

You've got a mind or you don't have a mind.

But perhaps we should--That's the objection,

and of course if that was right then again we might have to

conclude, well, whatever the mind is,

it's not quite like harmony is to the body.

But I'm not so sure we should agree that the mind can't come

in degrees. It can at least--The mental

aspects can come in degrees. We can have varying degrees of

intelligence, varying degrees of creativity,

varying degrees of reasonableness,

varying degrees of ability to communicate.

So just as, we might say, just as the functioning of the

harp can come in varying degrees--more or less

harmony--the functioning of the body in terms of its mind can

come in varying degrees. So that second objection

doesn't seem to me very compelling.

Third objection, Plato points out--Socrates

points out--that the soul can be good or it could be evil,

wicked. When the soul is good,

when you've got somebody who has got their stuff together,

we might speak of them as having a harmonious soul.

If the soul were to the body like harmony is to the

instrument and the soul can be harmonious,

it would seem as though we'd have to be able to talk about

harmony being harmonious. So just as we can talk about

the harmony of the soul, we'd have to be able to--if the

soul is like the harmony of the body--we'd have to be able to

talk about the harmony of the harmony.

But we don't talk about harmony of the harmony.

I'm not quite sure what to make of this objection.

This might be a point where it would be well to remind

ourselves of the fact that the suggestion was never that the

soul just literally is harmony. It's just similar to harmony,

says the physicalist, in the way that harmony gets

produced by the body--by the instrument.

In that same way, mind or mental activity gets

produced by the body. We don't have to say that

everything that's true of the mind is true of harmony and

everything that's true of harmony is true of the body--or

the mind. Still, I think there's a bit

more we can say in response to this objection,

and that's this: Just as it's true that we can

talk about minds or souls being good or wicked,

we can talk about different kinds of harmony.

There are--Certain harmonies are sweeter than others;

some of them are more jarring and atonal or discordant.