Professor Shelly Kagan: We've begun to turn to Plato's

dialogue Phaedo, and what I started doing last

time was sketching the basic outlines of Plato's

metaphysics--not so much to give a full investigation of

that--clearly we're not going to do that here--but just to

provide enough of the essential outlines of Plato's metaphysical

views so that we can understand the arguments that come up later

in the Phaedo, basically all of which or many

of which presuppose something--certain central

aspects about Plato's metaphysical views.

The key point behind his metaphysics then was the thought

that, in addition to the ordinary empirical physical

we have to posit the existence of a kind of second realm,

in which exist the Platonic--as they're nowadays called--the

The sort of thing that perhaps we might call or think of as

And the reason for positing these things is because we're

and yet, we recognize that the ordinary physical

world--although things may participate in them to varying

degrees--we don't actually come across these objects or entities

in the physical world. So that we can talk about

things being beautiful to varying degrees,

but we never come across beauty itself in the actual empirical

fact that two plus one equals three, but it's not as though we

ever come across numbers--number three itself--anywhere in the

distinguishes the empirical world from this--this realm of

Platonic ideal objects--is that indeed they--there's something

In contrast, physical objects are constantly

changing. Something might be short at one

point and become tall at another point, ugly at one point and

become beautiful--like the ugly duckling.

It starts out ugly and becomes a beautiful swan.

In contrast, justice itself never changes.

Beauty itself never changes. We have the thought that these

things are eternal, and indeed, beyond change,

In fact, if you start thinking more about the world from this

perspective, the world we live in is crazy.

Plato thinks of it as crazy in the way that a dream is.

When you're caught up in the dream, you don't notice just how

insane it all is. But if you step back and

I was eating a sandwich and suddenly the sandwich was the

Statue of Liberty, except the Statue of Liberty

ocean, except she's really a piece of spaghetti."

That's how dreams are. And when you're in it,

You're kind of caught up, but you step back and say,

"That's just insane." Well, Plato thinks that the

empirical world has something of that kind of insanity,

something of that kind contradictoriness,

built into it that we don't ordinarily notice.

"He's a basketball player, so he's really,

So he's really, really short for a basketball

so it's really, really big--except it's a baby

The world is constantly rolling--this is a Platonic

expression--rolling between one form and the other.

And it's hard to make sense of. In contrast,

the mind is able to grasp the Platonic ideas,

they're reliable, they are--they're law-like and

the Platonic picture. Now, it's not my purpose here

to try to argue for or against Platonism with regard to

abstract entities. As I suggested in talking about

the example of math last time, it's not a silly view,

even if it's not a view that we all take automatically.

But in thinking about math, most of us are inclined to be

makes it true that two plus one equals three,

but it's not the fact that empirical objects--We don't do

empirical experiments to see whether two plus one equals

grasp the truths about numbers. Plato thought everything was

for and against that view--just wanted to sketch it,

so as to understand the arguments that turn on it.

So for our purposes, let's suppose Plato was right

Well, Plato thinks what's going to follow is that we have some

reason to believe in the immortality of the soul as,

again, as we indicated last time, the picture is that the

mind--the soul--is able to grasp these eternal Platonic forms,

from thinking about them by the distractions provided by the

body--the desire for food, drink, sex, what have you,

the body, the mind, the soul, is able to better

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7. Plato, Part II: Arguments for the immortality of the soul

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