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  • 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

  • world that we're all familiar with,

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

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

  • Platonic forms or Platonic ideas.

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

  • abstract objects or abstract properties.

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

  • clearly able to think about these ideas,

  • 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

  • world. We are able to talk about the

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

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

  • empirical world. A further point that

  • distinguishes the empirical world from this--this realm of

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

  • perfect about them. They don't change.

  • 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 contrast to the empirical world.

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

  • perspective, the world we live in is crazy.

  • It's almost insanely contradictory.

  • 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

  • reflect on it, "Well, let's see,

  • I was eating a sandwich and suddenly the sandwich was the

  • Statue of Liberty, except the Statue of Liberty

  • was my mother. And she's flying over the

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

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

  • it sort of all makes sense. Right?

  • 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,

  • really tall, except he's only six feet.

  • So he's really, really short for a basketball

  • player. This is a baby elephant,

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

  • elephant, so it's really, really small."

  • 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,

  • the Platonic forms; and they're stable,

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

  • we can grasp them. They don't change;

  • they're eternal. That's, as I say,

  • 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

  • Platonists. We all do believe something

  • 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

  • three. Rather, we think our mind can

  • grasp the truths about numbers. Plato thought everything was

  • like that. Well, I'm not going to argue

  • 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

  • about that and ask, what follows?

  • 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,

  • the ideas. Typically, we're distracted

  • from thinking about them by the distractions provided by the

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

  • sleep. But by distancing itself from

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

  • concentrate on the forms. And if you're good at that,

  • if you practice while you're alive, separating yourself from

  • the body, then when your body dies,

  • the mind is able to go up to this Platonic heavenly realm and

  • commune with gods and other immortal souls and think about

  • the forms. But if you've not separated

  • yourself from the body while in life, if you're too enmeshed in

  • its concerns, then upon the death of your

  • body your soul will get sucked back in, reincarnated perhaps,

  • in another body. If you're lucky,

  • as another person; if you're not so lucky,

  • as a pig or a donkey or an ant or what have you.

  • So your goal, Plato says, your goal should

  • be, in life, to practice death--to separate yourself from

  • your body. And because of this,

  • Socrates, who's facing death, isn't distressed at the

  • prospect, but happy. He's happy that the final

  • separation will take place and he'll be able to go to heaven.

  • The dialogue ends, of course, with the death

  • scene--Socrates has been condemned to death by the

  • Athenians, and it ends with his drinking

  • the hemlock, not distressed but rather sort of joyful.

  • And the dialogue ends with one of the great moving death scenes

  • in western civilization and as Plato says--let's get the quote

  • here exactly right--"Of all those we have known,

  • he was the best and also the wisest and the most upright."

  • Just before the death scene, there's a long myth,

  • which I draw your attention to but I don't want to discuss in

  • any kind of detail. Plato says it's a story;

  • it's a myth. He's trying to indicate that

  • there are things that we can't really know in a scientific way

  • but we can glimpse. And the myth has to do with

  • these sort of pictures I was just describing where we don't

  • actually live on the surface of the Earth of in the light,

  • but rather live in certain hollows in the dark where we're

  • mistaken about the nature of reality.

  • Some of you who are maybe familiar with Plato's later

  • dialogue The Republic may recognize at least what seems to

  • me, what we have here,

  • is a foreshadowing of the myth of the cave, or the allegory of

  • the cave, which Plato describes there as

  • well. Our concern is going to be the

  • arguments that make up the center of the dialogue.

  • Because in the center of the dialogue, before he dies,

  • Socrates is arguing with his friends.

  • Socrates is saying, "Look, I'm not worried.

  • I'm going to live forever." And his disciples and friends

  • are worried whether this is true or not.

  • And so the heart of the dialogue consists of a series of

  • arguments in which Socrates attempts to lay out his reasons

  • for believing in the immortality of the soul.

  • And that's going to be our concern.

  • What I'm going to do is basically run through my attempt

  • to reconstruct--my attempt to lay out the basic ideas from

  • this series of four or five arguments that Plato gives us.

  • I'm going to criticize them. I don't think they work,

  • though I want to remark before I turn to them that in saying

  • this I'm not necessarily criticizing Plato.

  • As we'll see, some of the later arguments

  • seem to be deliberately aimed at answering objections that we can

  • raise to some of the earlier arguments.

  • And so it might well be that Plato himself recognized that

  • the initial arguments aren't as strong as they need to be.

  • Plato wrote the dialogues as a kind of learning device,

  • as a tool to help the reader get better at doing philosophy.

  • They don't necessarily represent in a systematic

  • fashion Plato's worked out axiomatic views about the nature

  • of philosophy. It could be that Plato's

  • deliberately putting mistakes in earlier arguments so as to

  • encourage you to think for yourself,

  • "Oh, this is--here's a problem with this argument.

  • There's an objection with that argument."

  • Some of these, Plato then may address later

  • on. But whether or not he does

  • address them--we're not doing Plato any honor,

  • we're not doing him any service,

  • if we limit ourselves to simply trying to grasp,

  • here's what Plato thought. We could do the history of

  • ideas and say, "Here's Plato's views.

  • Aren't they interesting? Notice how they differ from

  • Aristotle's views. Aren't they interesting?"

  • and move on like that. But that's not what the

  • philosophers wanted us to do. The great philosophers had

  • arguments that they were putting forward to try to persuade us of

  • the truths of their positions. And the way you show respect

  • for a philosopher is by taking those arguments seriously and

  • asking yourself, do they work or not?

  • So whether or not the views that are being put forward in

  • Socrates' mouth are the considered,

  • reflective judgments of Plato or not, for our purposes we can

  • just act as though they were the arguments being put forward by

  • Plato, and we can ask ourselves,

  • "Do these arguments work or don't they?"

  • So I'm going to run through a series of these arguments.

  • I'm going to, as I've mentioned before,

  • be a bit more exegetical than is normally the case for our

  • readings. I'm going to actually pause,

  • periodically look at my notes and make sure I'm remembering

  • how I think Plato understands the arguments.

  • Of course, since the dialogue is indeed a dialogue,

  • we don't always have the arguments laid out with a series

  • or premises and conclusions. And so it's always a matter of

  • interpretation, what's the best reconstruction

  • of the argument he's gesturing towards.

  • How can we turn it into an argument with premises and

  • conclusions? Well, that's what I'm going to

  • try to do for us. Also going to give the

  • arguments names. These are not names that Plato

  • gives, but it will make it easy for us to get a fix,

  • roughly, on the different arguments as we move from one to

  • the next. So the first argument,

  • and the worry that gets the whole things going,

  • is this. So, we've got this nice

  • Platonic picture where Plato says, "All right.

  • So the mind can grasp the eternal forms,

  • but it has to free itself from the body to do that."

  • And so, the philosopher, who has sort of trained himself

  • to separate his mind from his body,

  • to disregard his bodily cravings and desires--the

  • philosopher will welcome death because at that point he'll

  • truly, finally, make the final break

  • from the body. And the obvious worry that gets

  • raised in the dialogue at this point is this:

  • How do we know that when the death of the body occurs the

  • soul doesn't get destroyed as well?

  • That's the natural worry to have.

  • Maybe what we need to do is separate ourselves as much as

  • possible from the influence of our body without actually going

  • all the way and breaking the connection.

  • If you think about it like a rubber band, maybe the more we

  • can stretch the rubber band the better;

  • but if you stretch too far and the rubber band snaps,

  • that's not good, that's bad.

  • It could be that we need the body in order to continue

  • thinking. We want to free ourselves from

  • the distractions of the body, but we don't want the body to

  • die, because when the body dies the soul dies as well.

  • Even if we are dualists, as we've noticed before--even

  • if the soul is something different from the body--it

  • could still be the case, logically speaking,

  • that if the body gets destroyed, the soul gets

  • destroyed as well. And so, Socrates' friends ask

  • him, how can we be confident that the soul will survive the

  • death of the body and indeed be immortal?

  • And that's what prompts the series of arguments.

  • Now, the first such argument I dub "the argument from the

  • nature of the forms." And the basic thought is fairly

  • straightforward. The ideas or the forms--justice

  • itself, beauty itself, goodness itself--the forms are

  • not physical objects. Right?

  • We don't ever bump into justice itself.

  • We bump into societies that may be more or less just,

  • or individuals who may be more or less just,

  • but we never bump into justice itself.

  • The number three is not a physical object.

  • Goodness itself is not a physical object.

  • Perfect roundness is not a physical object.

  • Now, roughly speaking, Socrates' seems to think it's

  • going to follow straightforwardly from that that

  • the soul must itself be something non-physical.

  • If the forms are not physical objects, then Socrates thinks it

  • follows they can't be grasped. We can certainly think about

  • the forms, but if they're non-physical they can't be

  • grasped by something physical like the body.

  • They've got to be grasped by something non-physical--namely,

  • the soul. But although that's,

  • I think, the sketch of where Socrates wants to go,

  • it doesn't quite give us what we want.

  • On the one hand, even if it were true that the

  • soul must be non-physical in order to grasp the non-physical

  • forms, wouldn't follow that the soul

  • will survive the death of the body.

  • That's the problem we've been thinking about for the last

  • minute. And there's something puzzling.

  • We might wonder, well, just why is it that the

  • body can't grasp the forms? So there's a fuller version of

  • the argument that's the one I want to focus on.

  • And indeed, I put it up on the board.

  • So Platonic metaphysics gives us premise number one--that

  • ideas, forms, are eternal and they're

  • non-physical. Two--that which is eternal or

  • non-physical can only be grasped by the eternal and the

  • non-physical. Suppose we had both of those.

  • It would seem to give us three, the conclusion we want--that

  • which grasps the ideas or the forms must be eternal or

  • non-physical. What is it that grasps the

  • ideas or the forms? Well, that's the soul.

  • If that which grasps the ideas or the forms must be

  • eternal/non-physical, well one thing we're going to

  • get is, since that which grasps the

  • forms must be non-physical, the soul is not the body.

  • Since that which grasps the ideas or forms must be eternal

  • or non-physical--it's eternal, it's immortal.

  • All right. Let's look at this again more

  • carefully. Ideas or forms are eternal;

  • they're non-physical. Well, I've emphasized the

  • non-physical aspect, and I've emphasized as well

  • that they're not changing. But perhaps it's worth taking a

  • moment to emphasize the eternal aspect of the forms.

  • Now, people may come and go, but perfect justice--the idea

  • of perfect justice--that's timeless.

  • Nothing that happens here on Earth can change or alter or

  • destroy the number three. Two plus one equaled three

  • before there were people; two plus one equals three now;

  • two plus one will always equal three.

  • The number three is eternal, as well as being non-physical.

  • So the Platonic metaphysics says quite generally,

  • if we're thinking about the ideas or the forms,

  • the point to grasp is they're eternal;

  • they're non-physical. The crucial premise--since

  • we're giving Plato number one--the crucial premise for our

  • purposes is premise number two. Is it or isn't it true that

  • those things which are eternal or non-physical can only be

  • grasped by something that is itself eternal and non-physical?

  • Again, it does seem as though the conclusion that he wants,

  • number three, follows from that.

  • If we give him number two, it's going to follow that

  • whatever's doing the grasping--call that the soul

  • since the soul is just Plato's word for our mind--if whatever's

  • doing the grasping of the eternal and non-physical forms

  • must itself be eternal and non-physical,

  • it follows that the soul must be non-physical.

  • So the physicalist view is wrong and the soul must be

  • eternal. The soul is immortal.

  • So Socrates has what he wants, once we give him premise number

  • two, that the eternal, non-physical can only be

  • grasped by the eternal, non-physical.

  • As Socrates puts it at one point, "The impure cannot attain

  • the pure." Bodies--corruptible,

  • destroyable, physical, passing--whether they

  • exist or not, whether they exist for a brief

  • period and then they cease to exist--these impure objects

  • cannot attain, cannot grasp,

  • cannot have knowledge of the eternal, changeless non-physical

  • forms. "The impure cannot attain the

  • pure." That's the crucial premise,

  • and what I want to say is, as far as I can see there's no

  • good reason to believe number two.

  • Now, number two is not an unfamiliar--premise number two

  • is not an unfamiliar claim. I take it the claim basically

  • is that, to put it in more familiar language,

  • it takes one to know one. Or to use it,

  • slightly other kind of language that Plato uses at various

  • points, "Likes are known by likes."

  • But it takes one to know one is probably the most familiar way

  • of putting the point. Plato's saying,

  • "What is it that we know? Well, we know the eternal forms;

  • takes one to know one. So we must ourselves be

  • eternal." Unfortunately,

  • this thought, popular as it may be,

  • that it takes one to know one, just seems false.

  • Think about some examples. Well, let's see,

  • a biologist might study, or a zoologist might study,

  • cats. Takes one to know one,

  • so the biologist must himself be a cat.

  • Well, that's clearly false. You don't have to be feline to

  • study the feline. Takes one to know one;

  • so, you can't be a Canadian and study Mexicans,

  • because it takes one to know one.

  • Well, that's just clearly stupid.

  • Of course the Canadians can study the Mexicans and the

  • Germans can study the French. It does not take one to know

  • one; to understand the truths about

  • the French, you do not yourself need to be French.

  • Or take the fact that some doctors study dead bodies.

  • Aha! So to study and grasp things

  • about dead bodies, corpses, you must yourself be a

  • dead body. No, that certainly doesn't

  • follow. So if we start actually pushing

  • ourselves to think about examples--does it really take

  • one to know one--the answer is, at least as a general claim,

  • it's not true. It doesn't normally take one to

  • know one. Now, strictly speaking,

  • that doesn't prove that premise two is false.

  • It could still be that, although normally you don't

  • have to be like the thing that you're studying in order to

  • study it, although that's not normally

  • true, it could be that in the particular case of non-physical

  • objects, in the particular case of

  • eternal objects, you do have to be eternal,

  • non-physical to study them. It could be that even though

  • the general claim, "it takes one to know one" is

  • false, the particular claim,

  • "eternal, non-physical can only be grasped by the eternal,

  • non-physical," maybe that particular claim is true.

  • And it's only the particular claim that Plato needs.

  • Still, all I can say is, why should we believe two?

  • Why should we think there's some--Even though,

  • normally, the barrier can be crossed and Xs can study the

  • non-X, why should that barrier

  • suddenly become un-crossable in the particular instance when

  • we're dealing with Platonic forms?

  • Give us some reason to believe premise two.

  • I can't see any good reason to believe premise two,

  • and as far as I can see, Plato doesn't actually give us

  • any reason to believe it in the dialogue.

  • Consequently, we have to say,

  • as far as I can see, we haven't been given any

  • adequate argument for the conclusion that the soul--which

  • admittedly can think about forms and ideas--we have no good

  • reason yet to believe, to be persuaded,

  • that the soul must itself be eternal and non-physical.

  • That's the first argument. As I say though,

  • Plato may well recognize the inadequacy of that argument,

  • because after all Socrates goes on to offer a series of other

  • arguments. So let's turn to the next.

  • I call the second argument "the argument from recycling"--not

  • the best label I suppose, but I've never been able to

  • come up with a better one. And the basic idea is that

  • parts get re-used. Things move from one state to

  • another state and then back to the first state.

  • So, for example, to give an example that Plato

  • actually gives in the dialogue, we are all awake now,

  • but previously we were asleep. We went from being in the realm

  • of the asleep to being in the realm of the awake,

  • and we're going to return from the realm of the awake back to

  • the realm of the asleep and over and over and over again.

  • Hence, recycling. I think that actually a better

  • example for Plato's purposes, not that I expect him to have

  • this particular example, but, would be a car.

  • Cars are made up of parts that existed before the car itself

  • existed. There was the engine and the

  • steering wheel and the tires and so forth.

  • And these parts got assembled and put together to make up a

  • car. So the parts of the car existed

  • prior to the existence of the car itself.

  • And the time is going to come when the car will cease to exist

  • but its parts will still be around.

  • Right? It'll get taken apart for

  • parts, sold for parts. There will be the distributor

  • cap, and there will be the tires, and there will be the

  • carburetor, there will be the steering wheel.

  • Hence, the name, that I dub the argument,

  • "the argument from recycling." That's the nature of reality

  • for Plato. And it seems like a plausible

  • enough view. Things come into being by being

  • composed of previously existing parts.

  • And then, when those things cease to have the form they had,

  • the parts get used for other purposes.

  • They get recycled. If we grant that to Plato,

  • he thinks we've got an argument for the immortality of the soul.

  • Because after all, what are the parts that make us

  • up? Well, there are the various

  • parts of our physical body, but there's also our soul.

  • Remember, as I said, in introducing the

  • Phaedo, Plato doesn't so much argue for

  • the existence of something separate,

  • the soul, as presuppose it. His fundamental concern is to

  • try to argue for the immortality of the soul.

  • So he's just helping himself to the assumption that there is a

  • soul. It's one of the parts that

  • makes us, that goes up into making us up,

  • goes into making us up. It's one of the pieces that

  • constitutes us. Given the thesis about

  • recycling, then, we have reason to believe the

  • soul will continue to exist after we break.

  • Even after our death, our parts will continue to

  • exist. Our body continues to exist

  • even after our death. Our soul will continue to exist.

  • Well, there's a problem with the argument from recycling,

  • and it's this. Even if the recycling thesis

  • shows us that we're made up of something that existed before

  • our birth and that some kinds of parts are going to have to exist

  • after our death, we can't conclude that the soul

  • is one of the parts that's going to continue to exist after our

  • death.

  • Consider some familiar facts about human bodies.

  • As we nowadays know, human bodies are made up of

  • atoms. And it's certainly true that

  • the atoms that make up my body existed long before my body

  • existed. And it's certainly true that

  • after my death those atoms are going to continue to exist.

  • So there's some--and will eventually get used to make

  • something else. So Plato's certainly right

  • about recycling as a fundamental truth.

  • The things that make me up existed before,

  • and will continue to exist after my death.

  • But that doesn't mean that every part of my body existed

  • before I was born, and that every part of my body

  • will continue to exist after I die.

  • Take my heart. My heart is a part of my body.

  • Yet, for all that, it didn't exist before my body

  • began to exist. It came into existence as part

  • of, along with, the creation of my body,

  • and it won't continue to exist, at least not very long,

  • after the destruction of my body.

  • There'll be a brief period in which, as a cadaver I suppose,

  • my heart will continue to exist.

  • But eventually my body will decompose.

  • We certainly wouldn't have any grounds to conclude my heart is

  • immortal, will exist forever. That just seems wrong.

  • So even though it's true that some kind of recycling takes

  • place, we can't conclude that everything that's now a part of

  • me will continue to exist afterwards.

  • It might not have been one of the parts, one of the

  • fundamental parts, from which I'm built--like the

  • heart. And if that's right,

  • if there can be parts that I have now that weren't one of the

  • parts from which I was made, there's no particular reason to

  • think it's going to be one of the parts that's going to

  • continue to exist after I die. Once we see that kind of worry,

  • we have to see, look, the same thing could be

  • true for the soul. Even if there is an immortal

  • soul--Sorry. Even if there is a non-physical

  • soul that's part of me, we don't yet have any reason to

  • believe that it's one of the fundamental building blocks that

  • were being recycled. We don't have adequate reason

  • to conclude that it's something that existed before I was put

  • together, it's something that will be

  • recycled and continue to exist after I fall apart,

  • after my body decomposes, after I'm separated from my

  • body, or what have you. Even if recycling takes place,

  • we don't have any good reason yet to believe that the soul is

  • one of the recycled parts. So it seems to me "the argument

  • from recycling," as I call it, is not successful either.

  • Now, as I say, many times when you read the

  • dialogue, this or other dialogues by Plato,

  • it seems as though he's fully cognizant of the objections that

  • at least an attentive reader will raise about earlier stages

  • of the argument. Because sometimes the best way

  • to understand a later argument is to see it as responding to

  • the weaknesses of earlier arguments.

  • And I think that's pretty clearly what's going on in the

  • very next argument that comes up in the dialogue.

  • The objection I just raised, after all, to the argument from

  • recycling, said, in effect, even though some

  • kind of recycling takes place, not all my parts get recycled,

  • because not all of my parts were among the pre-existing

  • constituent pieces from which I am built up.

  • We don't have any particular reason to think my heart's one

  • of the prior-existing pieces; we don't have any good reason

  • to assume that my soul's one of the prior-existing pieces.

  • Well, Plato's very next argument attempts to persuade us

  • that indeed we do have reason to believe that the soul is one of

  • the prior-existing pieces. And this argument is known as

  • "the argument from recollection."

  • The idea is, he's going to tell us certain

  • facts that need explaining, and the best explanation

  • involves a certain fact about recollecting,

  • or a certain claim about recollecting or remembering.

  • But we can only remember, he thinks, in the relevant way

  • if our soul existed before the birth of our body,

  • before the creation of our body.

  • All right. What's the crucial fact?

  • Well, let's start by--Plato starts by telling us,

  • reminding us of what it is to remember something.

  • Or perhaps a better word would be what is it to be reminded of

  • something by something else that resembles it but is not the

  • thing it reminds you of. I might have a photograph of my

  • friend Ruth. And looking at the photograph

  • reminds me of Ruth. It brings Ruth to mind.

  • I start thinking about Ruth. I remember various things I

  • know about Ruth. The photograph is able to do

  • that, is able to trigger these thoughts.

  • But of course, the photograph is not Ruth.

  • Right? Nobody would--who's thinking

  • clearly--would confuse the photograph with my friend.

  • But the photograph resembles Ruth.

  • It resembles Ruth well enough to remind me of her,

  • and interestingly, it can do that even if it's not

  • a very good photograph. You might hold up the

  • photograph and I might say, "Gosh, that really doesn't look

  • very much like Ruth does it?" Even though I see that it is a

  • photograph of Ruth; it reminds me of her.

  • Now, how could it be that a photograph reminds me of my

  • friend? Well, this isn't some deep

  • mystery. Presumably the way it works is,

  • as I just said, it looks sort of like her.

  • It doesn't have to look very much like her.

  • It looks sort of like her. Your young brother or sister,

  • or my little children, can draw pictures of family

  • members that barely look like family members.

  • My niece drew a picture of my family once when she was three.

  • It didn't look very much like us at all, but we could sort of

  • see the resemblance in a vague kind of way, right?

  • So it's got to look at least somewhat like the missing

  • friend. But that's not enough.

  • You've never met Ruth, let's suppose.

  • I hold up the photograph without having told you anything

  • about her. The photograph's not going to

  • remind you of Ruth. Why not?

  • Well, you don't know Ruth. So the pieces we need are not

  • only an image of Ruth, even if an imperfect image of

  • Ruth, we also need some prior acquaintance with Ruth.

  • That's pretty much what it takes, right?

  • So on the one hand--temporal sequence--first you know Ruth,

  • you meet Ruth, you get to know Ruth.

  • Then at a later time you're shown an image of Ruth--maybe

  • not even an especially good image of Ruth--but good enough

  • to remind you. And suddenly,

  • you're remembering things you know about Ruth.

  • That's how recollection works.

  • All right. Now, Plato points out that we

  • all know things about the Platonic forms.

  • But the Platonic forms, as we also know,

  • are not to be found in this world.

  • The number three is not a physical object,

  • perfect roundness is not a physical object,

  • perfect goodness is not a physical object.

  • We can think about these things; our mind can grasp them,

  • but they're not to be found in this world.

  • Yet, various things that we do find in this world get us

  • thinking about those things.

  • I look at the plate on my kitchen table,

  • it's not perfectly round, it's got imperfections;

  • but suddenly I start thinking about circles,

  • perfectly round objects. I look at somebody who's pretty.

  • He or she is not perfectly beautiful, but suddenly I start

  • thinking about the nature of beauty itself.

  • Ordinary objects in the world participate to a greater or

  • lesser degree in the Platonic forms.

  • That's Plato's picture of metaphysics.

  • And we bump up against, we look at, we have

  • interactions with these everyday objects and,

  • somehow, they get us thinking about the Platonic forms

  • themselves. How does it happen?

  • Plato has a theory. He says, "These things remind

  • us of the Platonic forms." We see something that's

  • beautiful to some degree, and it reminds us of perfect

  • beauty. We see something that's more or

  • less round, and it reminds us of perfect circularity.

  • We see somebody who's fairly decent morally,

  • and it reminds us of perfect justice or perfect virtue.

  • It's just like the photograph, perhaps the not very good

  • photograph, that reminds me of my friend Ruth.

  • All right. Well, there's an explanation of

  • how it could be that things that are not themselves perfectly

  • round could remind us, could make us think about

  • perfect roundness. But then Plato says,

  • "Okay, but keep in mind all of what you need in

  • order to have reminding, to have recollecting take

  • place." In order for the photograph to

  • remind me of Ruth, I have to already have met

  • Ruth. I have to already be acquainted

  • with her.

  • In order for a more or less round plate to remind me of

  • roundness, Plato says, I have to have already met

  • perfect roundness itself. In order for a more or less

  • just society to remind me of justice itself,

  • so that I can start thinking about the nature of justice

  • itself, I have to somehow have already

  • been acquainted with perfect justice.

  • But how and when did it happen? Not in this life,

  • not in this world. In this world nothing is

  • perfectly round, nothing is perfectly beautiful,

  • nothing is perfectly just. So it's got to have happened

  • before. If seeing the photograph of my

  • friend now can remind me of my friend, it's got to be because I

  • met my friend before. If seeing things that

  • participate in the forms remind me of the forms,

  • it's got to be because I've met or been acquainted directly with

  • the forms before. But you don't bump up against,

  • you don't meet, you don't see or grasp or

  • become directly acquainted with, the forms in this life.

  • So it's got to have happened before this life.

  • That's Plato's argument. Plato says, thinking about the

  • way in which we grasp the forms helps us to see that the soul

  • must have existed before birth, in the Platonic heavenly realm,

  • directly grasping, directly communing with,

  • directly understanding the forms.

  • It's not taking place in this life, so it has to have happened

  • before. Well, look, now we've got the

  • kind of argument we were looking for.

  • Earlier the objection was, we had no good reason to think

  • the soul was one of the building blocks from which we're

  • composed; we have no good reason to think

  • it's one of the pieces that was around before our body got put

  • together, before our birth. Socrates says, "No.

  • On the contrary, we do have reason,

  • based on the argument from recollection,

  • to conclude that the soul was around before we were born."

  • All right. So the next question is,

  • is the argument from recollection a good one?

  • Now, let's say, I'm not really much concerned

  • with whether this was an argument that Plato thought

  • worked or not. Our question is,

  • do we think it works or not?

  • Although this is a form of an argument that Plato does put

  • forward in other dialogues as well,

  • and so it strikes me so there's at least some reason to think

  • this is an argument that he felt might well be right.

  • The crucial premise--Again, we're going to just grant Plato

  • the metaphysics. The crucial question is going

  • to be, is it right that in order to explain how it is we could

  • have knowledge of the forms now that we have to appeal to a

  • prior existence in which we had direct acquaintance?

  • It's not obvious to me that that's true.

  • It's not obvious to me for a couple of reasons.

  • One question is this: Is it really true that in order

  • to think about the perfectly straight,

  • I must have somehow, somewhere at some point come up

  • against, had direct knowledge of,

  • the perfectly straight? Isn't it enough for me to

  • extrapolate from cases that I do come up against in this life?

  • I come across things that are bent;

  • I come across things that are more straight,

  • more and more straight. Can't my mind take off from

  • there and push straight ahead to the idea of the perfectly

  • straight, even if I never have encountered it before?

  • Let me stop with this idea. Even if Plato is right,

  • that we need to have acquaintance with the Platonic

  • forms themselves in order to think about them,

  • and even if Plato is right that we never get the acquaintance in

  • this world, in the interaction with

  • ordinary physical objects, why couldn't it be that our

  • acquaintance with the Platonic forms comes about in this life

  • for the very first time? That's the question,

  • or that's the objection, that we'll turn to at the start

  • of next class.

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

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