Yes: Keith Yandell, University of Wisconsin at Madison
No: Clifford Williams, Trinity College
February 20, 2002
Trinity College, Deerfield, Illinois
Chris Firestone: The Department of Philosophy and the Honors Program at Trinity College are sponsoring this debate tonight. We are delighted to have with us two professors of some notoriety on a very interesting topic. The topic is, “Does life after death require dualism?” From Trinity College is Cliff Williams, whom you are familiar with. He is from Indiana University—that’s where he did his Ph.D.—and has written numerous books. I won’t go into all those details to save time. And professor Keith Yandell has graciously joined us here for the debate. He did his Ph.D. at Ohio State University, so we have a Big Ten rivalry here on Trinity’s grounds. I did a degree at the University of Illinois so I should be able to moderate with some efficiency here.
Here’s how we’re going to lay it out. We’re going to flip a coin to start, in the spirit of good competition. And then we’re going to give eight min or thereabouts to each person for opening comments. Then we’re going to have about twelve minutes for each person to ask questions of the other. If you’re a mathematician you’ll know this comes out to forty minutes, which will leave us with twenty minutes remaining. For those of you out there who are dying to ask a question, you can go ahead and raise your hand. For the purposes of longevity so that we can have this thing on tape for future generations, if you would be so kind as to come up after you raise your hand and are identified, come up to the microphone—that way we will be able to hear you. Prof. Yandell, since you’re our guest, would like to make the call?
Keith Yandell: Heads.
Chris Firestone: Is it heads?
Keith Yandell: Yes it is.
Chris Firestone: What would you like to do? Would you like to go first?
Keith Yandell: I’m happy to go any way you like. I am a little surprised at the influence of the National Football League at Trinity College!
Cliff Williams: Our subject is, “Does life after death require dualism?” Our subject is not, “Is dualism true or is Christian materialism true?” However, I would like to say that that’s the background for the debate. “Is Christian materialism compatible with life after death?” My position is “Yes,” and Professor Yandell’s position is “No.” But first a little bit of background.
Christian dualism has been the prominent position of most Christians. Christian materialism has been a minority position. Some of the Christian theologians in the first few centuries were Christian materialists, and recently Christian materialism has been enjoying a revival, “enjoying,” that is, according to the Christian materialists. It is probably accurate to say that the interlude has largely been one of Christian dualism. There are very few Christian materialists, but there have more in the last twenty to twenty-five years. And that raises our question for tonight—“Can the Christian materialist account for life after death?” I want to give a couple of definitions here, and Professor Yandell has agreed to amend them.
Dualism is the thesis that people consist of two sorts of substances—one matter and one non-matter. A nonmaterial substance is often called the soul or mind. Christian materialism is the thesis—
no, materialism is the thesis that people in a sense are only one kind of substance—matter or what is physical. It is anthropological materialism. It is not atheism, and Christian materialists do not conceive of themselves as benign to the existence of God. They are Christians and they are theists.
The attack on dualism by Christian materialists has had three prongs. One thesis put forward by Christian materialists says that the Bible does not support dualism. Number two, Christian materialists claim that the philosophical arguments for dualism are inaccurate, and there are a number of those. And number three, a positive reason that has been presented for Christian materialism is based on science as its thesis, that the scientific account of human activity can be given in physical terms only. Christian materialists don’t use this as what might be called a truth-conferring reason, but as an indication that non-material souls are not needed.
I would like to give a quotation from John Locke, a well-known early modern philosopher. John Locke was a dualist. But he thought that Christian materialism was a consistent position. He writes, “All the great ends of morality and religion are well enough secured, without philosophical proofs of the soul’s immateriality” (An Essay Concerning Human Understanding [Dover, 1959], Book IV, Chapter III, Section 6, p. 195). In other words, he thought that all the things Christians have though and maintain about people are consistent with materialism, with the thesis that people are purely material. And he thought this also about life after death, which is our subject for tonight. Even if we were purely material God could restore us in another world and give us retribution according to our doings in this life. So, technically speaking, a dualist could maintain the position that I am maintaining tonight. Typically dualists do not, because one of the things that dualists appeal to in the portrait of dualism is the claim that we live beyond the grave and that in order to account for that we need to believe in dualism.
I would like to address the consistency claim. I’ve just been giving some background here to give a picture or a context to our question. The question is, How can you believe that there is life beyond the grave if you believe that people are purely material? After all, bodies die. And there doesn’t seem to be anything there. Well, the Christian answer here is that people will be resurrected. And the understanding—this comes from 1 Corinthians 15—the understanding of that resurrection is re-creation. Re-creation is God’s making new what has died. The question is, How can you say that what has been re-created is the same as what has died? Re-creation presupposes that God is going to judge us, and we can’t be judged unless we are the same person. So the attack by the Christian dualist is simply to say that it’s not the same person, and so we need to postulate a non-physical soul, a non-physical substance, that remains beyond the grave and which accounts for the identity of the person who lives beyond death with the person who lived before death, so that when God judges, God is judging the same person. After all, we are accountable for our own sins, and duplicates of us are not accountable for our sins. I would like to maintain that this re-created person is the same as the pre-death person.
What I would like to say is that there is parity here. There is parity in some respect. It seems to me that the dualist has exactly the same problem that the Christian materialist has. After all, the Christian dualist believes in resurrection, and so the Christian dualist wants also to believe that the resurrected person is the same as the pre-death person and must therefore believe that the body of the person is the same. And so whatever account that the Christian dualist gives of the post-death person’s body being identical with the pre-death person’s body is an account that a Christian materialist could also accept. So that’s my thesis with regard to the identity issue here. There are other issues that perhaps will come up in our discussion, but this is a central one that I know Professor Yandell is going to insist on.
Keith Yandell: First, it’s a pleasure to be here. As you may know, I am allowed on occasion to visit Trinity Seminary and I am even an adjunct Professor of Philosophy of religion there, which is a like to me and I am very glad to be here. I will not say much about the exegesis of the New Testament. I am not a biblical scholar. I agree that dualism was a very early Christian view, held I think by Jesus and Paul, to pick two winners. If you want what I think is the best discussion of the New Testament teaching regarding this matter is to be found in a book by John Cooper called Body, Soul, and the Life Everlasting. The evidence that the New Testament teaches a dualistic view of human beings is laid out there with a kind of exquisite care that frankly a philosopher always wishes that he or she could find in a biblical theologian but does not always.
I find myself unable to separate the question of consistency and the question of truth. But does the Bible’s view of death require dualism? No, it requires either dualism or idealism. Idealism is the view that human beings are minds of a certain kind, and that what we call physical objects are simply experiences that human beings have that have conscious content. While I am not an idealist, idealism is perfectly compatible, so far as I can see, with the notion of life after death.
Materialism, I think, is not, or if it is, it is in that peculiar sense that a self-contradiction is compatible with anything as well as being incompatible with anything. My essential problem with materialism is that I think that it is not really false but that it’s necessarily false. That there aren’t any possible worlds in which it is true. And I will now argue for that.
There are varieties of materialism. I’m not going to try in eight minutes even to describe each of the varieties. Let me simply take materialism at its most straightforward. At its most straightforward, materialism is the doctrine that you are identical to your body. And hence whatever happens to your body happens to you and whatever happens to you happens to your body because you’re numerically identical to your body. Now strictly we all know that that’s not true. I mean, none of us when we clip our nails or go get a haircut worry about our personal identity being threatened. The actual view is that you’re identical to some crucial parts of your body. I won’t go into how much of us has to be around for that—whether the brain in a vat will do or whatever. Prof. Williams is of course quite right that contemporary materialism has either like a bright sun lightened the day or like a cancer grown through the body—we disagree on which of those is the right metaphor—then spread through the Christian academic world. On the strict view of materialism, as I say, a person is identical to a body.
Now bad things are going to happen to you. You’re going die, and you’ll be cremated, or buried, or buried at sea, or eaten by animals, or like Jeremy Bentham almost mummified and put in a glass cage. But bad things are going to happen to your body. And on this field they’re going to happen to you.
There are two responses to that, or three, depending on how you want to count them. The Christian philosopher from Notre Dame Peter van Inwagen says what happens is this. You die, and a little speck of you remains. And in that speck your life is dormant. Then at the last day, at the Day of Judgment, that speck is such that its life no longer is dormant. It’s awakened. You used to be able at Walgreen’s to get this little package of dust, and these seahorses would come out. You poured the seahorses into the water and first it’s dust and then its seahorses. And I guess according to the van Inwagen theory that’s why there’s a river in the book of Revelation mentioned in heaven. Okay, there’s one view.
The other view is by Kevin Corcoran who teaches at Calvin College. On Corcoran’s view, what happens is that at the time of your death, or just before, God causes this body to cause both a corpse and another body that goes to heaven. And so suddenly your one body—zap!—causes two bodies, one of which gets buried and one goes to heaven or one goes to the other place. I’ve got to admit that the Christian materialists are inventive.
There’s a principle; in fact, there are two. Let me state them as quickly and simply as I can. Here’s one. There’s a thing in philosophy that’s called the principle of the necessity of metaphysical identity. What lies behind that fancy phrase is just this. Let’s suppose, which I imagine is probably true, that you are now the same person you were when you came into this room. What the principle of the necessity of metaphysical identity tells you is that there isn’t any other person you could be. If you’re identical to a person who came into this room then there isn’t any other person that you could be identical to than that one.
But now think about this a minute. Here’s a third view, by the way. It might just be that what happens at death is that various parts of you get scattered, and at the end God reassembles you. Resurrection is reassembly. On the second view, resurrection is the creation of a new body and a corpse—two for the price of one. On the first view, the middle view, your survival is the survival of the speck in which your life is dormant. And on the third view, when you die you just get scattered, your atoms get scattered throughout the world. On the second account, resurrection is the creation of two bodies, one of which is living and is you. Resurrection on the first view—you drop the speck in the water and you get, not the seahorse, but you. In this third one, you’re reassembled.
But now if that can happen once, it can happen twice. And so there could be two bodies, or two specks in which your life survives. Or you could be reassembled twice. The parts of you at 14 and the parts of you at 24 could all be brought back together. In each case there’d be two you’s, according to a physicalist or materialist view. You’d be identical to each of two things that were not identical to one another. It is logically impossible that any one thing be identical to two things that are not identical to one another. Therefore what materialism of this straightforward sort entails is that something that is logically impossible could happen. Nothing logically impossible can happen. Therefore this materialist view is self contradictory. Therefore it’s false. Therefore it follows both that you won’t be raised from the dead and you won’t anything false.
There’s a second difficulty. The second difficulty, if I can get it in quick, is this. It isn’t possible that the sheer existence of something other than you prevents your existence. Now look at the scenario. If we get one speck, we get you, according to materialism. If we get two specks, we don’t get you. If we get some other speck taken from your body, we still get you. So on the materialist view, the following can happen. The existence of “two you’s” can keep you from existing at all even though they don’t do anything to one another. They don’t hit each other, hate each other, think unkind thoughts about each other. Now that’s impossible. So there are two reasons why straightforward materialism is logically impossible. Anything logically impossible is false. Hence materialism is false. Amen.
Chris Firestone: We’ll turn it over to questions, if you have questions for one another.
Cliff Williams: Yes, I agree with you that the Christian materialists are very inventive. These views that you presented are so inventive that I must confess that I’m not tempted to believe them either. First, I think they all presuppose the thesis that there must be some sort of continuity, or some sort of material, that’s in both the pre-death person and the post-death person. But I’m proposing something different, something that I would think of as boring, perhaps even more common sense. I’m proposing re-creation. So I want to ask you a question just to test you. I think I know how you’re going to answer. But I want to ask the question anyway.
Just imagine that one of us up here disappears. Poof. Gone. Of course, the audience would have quite a bit of puzzlement and maybe even a good deal of consternation. But let’s suppose after twenty or thirty seconds Chris comes back and just resumes talking, without apparent knowledge of his disappearance. Would you be inclined to say that this is the same person that came back, I mean, the same physical person? I guess I want a yes or a no answer.
Keith Yandell: You’re not going to get a yes or a no answer. That’s one of the delightful things about this not being a courtroom.
I wondered what you meant by re-create in your talk and I figured you’d get around to that. It may be, and you can tell me, it may be that you mean the following—that it’s perfectly possible that some physical thing just becomes invisible. That, I suppose, is possible. Or you might mean that a thing’s atoms are scattered just thin enough for awhile so that it cannot be seen, or that it becomes completely transparent. But you probably don’t mean any of those things. If you mean by re-create, creation in a literal sense, then to create something is to make it the case that there is something new which is in no way made out of anything that pre-existed it. The doctrine of creation, as you know as well as I, is typically a doctrine of creation from nothing, where nothing isn’t thought of as a kind of very, very thin stuff, like tapioca with the lumps taken out. It means literally there not being anything. First there isn’t anything and then there is something. And the something there is isn’t made out of prior stuff. Now is that what you mean by re-creation, the creation of something—it is annihilated, it doesn’t exist anymore at all, and then it exists again?
Cliff Williams: Well, I’m happy to take that view. The kind of creation I mean is the kind of creation that God is going to perform on resurrection day. I’m not so sure what exactly that is. There is some indication that we are going to be different. After all, 1 Cor. 15 refers to us as having spiritual bodies. I’m not too sure, though, what a spiritual body is. I mean, if you take spiritual to mean incorporeal, then you get an outright contradiction, so it doesn’t mean that. But it does mean that there’s something different about us from what we were in the pre-death stage. And what takes place doesn’t seem like a reassembly. I’m not sure why God would have to use the parts of us that existed. In fact, God isn’t going to be able to use all the parts. If God wanted to, God could use most of the parts, and that certainly would be sufficient to satisfy the continuity requirement. But the point of my fanciful example is that if we’ve got the same personality, then we’ve got the same person, if everything else is the same. That was part of my question for which I did not get a yes or no answer. My supposition is that you would say, “Oh, Cliff, I’m glad you’re back.”
Keith Yandell: I would because I don’t believe it’s possible for you to be annihilated.
Cliff Williams: Thank you.
Keith Yandell: I don’t think it’s going to be happen that you’re annihilated. God could annihilate you, but no doubt he would never do this. You’re much too nice.
But, no, I would not believe you were annihilated. I would make something strange out of it. There are philosophers, though, who say what you are saying. If you want a good version of it, you can find it in a book called Objects and Persons by Trenten Merricks. Merricks teaches at the University of Virginia. He is a devout Christian and a fine philosopher. Merricks thinks that the following can happen—a material thing can exist at time t, not exist at all, not be scattered, not be thinned out, but simply be annihilated for the next few trillion years, and then be re-created.
Now I don’t know what to say. To prove something, you need to find something more evidently true from which it follows. And I don’t know anything more evidently true than that that can’t happen, from which it follows that that can’t happen. It seems to me that if I give you my only copy, the only copy in the whole world of Ralph Cudworth’s The True Intellectual System of the Universe, and you manage to utterly annihilate it, then the best you can do is give me a copy of it. The best you can do, the best that can be done, is that an exact copy be made, which is not the original. I don’t know any truth that is more clearly true than that. So I don’t think re-creation in that sense is an option.
But, by the way, on my view, my body is just whatever body I, that is, my mind or soul, is embodied in. So for me to get my body back is just for me to get a body which then is my body. And I of course agree with you about the peculiar, the unusual, the wonderful properties of the resurrection body, a body like unto the body of Jesus, after Jesus’ resurrection, which has very remarkable properties compared with the bodies we have now. I don’t think that reassembly is necessary; that’s part of one materialist doctrine. I think what is required for me to be resurrected is for me to again be embodied, in whatever kind of body a spiritual body is. But a materialist can’t possibly offer that account. Materialists can’t possibly offer the account that my resurrection body will be the body in which my soul is embodied, because of course the materialist doesn’t think I have a dualist sense of soul.
Cliff Williams: Maybe we have come to a parting of the ways here, a basic difference. As you say, it is difficult to prove it either way. I used my example to try to get you to have an intuition, to see that, yes, it is possible to have a re-creation. You cite the book case. But people are different from books, and it strikes me that if we’ve got a re-creation, and we encounter a recreated person, we ask this recreated person questions about their memories, and we look at who they are, we’d say, yes, this really is the same person. And it wouldn’t matter to us that there was different matter involved. In fact, scripture seems to indicate that there is different matter. So I think at this point we’ve just got different intuitions. And I’m not too sure how to prove it either way. You’ve got an example; I’ve got an example. And you claim that it’s, I think you claim that, it is logically impossible. That doesn’t strike me as true. It strikes me as possible for God to do because God will in fact do it. I’m not saying here that God is doing something contradictory. I don’t think I’m claiming that.
And I think there’s a parity here too because I think the dualist has the same difficulty. I’m puzzled about that. After all, suppose the non-material soul were duplicated. Which one would we say is the real you? So it’s puzzling that dualists use this argument against materialists when it really could be used also against dualism. So it seems that therefore it has no effect on either of them, on either side.
Keith Yandell: Well, I suggest it doesn’t apply to dualism at all. Dualism allows, if you’d like, cloning. The cloning of the soul is just making a copy. So if you’ve got a soul, it exists, and then if you make a copy of it, that would not have any effect whatever on the original. The question is, “Which is the one that’s been around?” Let’s suppose you can’t tell. Well then you can’t tell. But we’re doing metaphysics, not theory of knowledge. Whichever one in fact is the one that started out and is still around is the one that started out. The reduplication argument has no purchase on dualism at all.
In terms of just contrary intuitions, let’s now check that one out. Here’s a different kind of materialism. A different kind of materialism says, “Look, let’s forget material substances. What persons are is just material states. Here’s one material state, or one collection of material states, here’s another collection of material states.” And if you’re very generous to the materialists, and I will be, let’s just suppose that material states can have dispositions, tendencies, feelings, habits. I’m not at all sure that works out, but let’s not worry about it, okay? So personalities are identical to persons.
Personalities are sequences of material states, one after another with each member of the series caused by the preceding member. But then of course the states can branch, and the same kind of duplication issue arises, if you think a person is simply a series of states and if you think a person is a single enduring material body. Now here you can play the game on both sides of the street. It doesn’t matter whether these are mental states which are identical to physical states, or whether they are mental states which are not identical to physical states. What follows is that one ought to be a substance dualist, one ought to be a really robust dualist, down to the ground. What a person is, is a mental substance, a thing capable of self-consciousness. So for any view in which there is a series of states and that’s what a person is, you get the same problems as you do for the more straightforward materialism.
Cliff Williams: But therefore would not the materialist be vindicated since the dualist has the same problems? Isn’t that right?
Keith Yandell: A dualist thinks there are two kinds of substances.
Cliff Williams: Correct.
Keith Yandell: For somebody who thought a person resembles conscious states, and there aren’t any conscious states, then the dualist faces a problem. And they don’t affect each other, but they prevent the continuation of the first. Both of those suggestions apply. But to dualism it won’t apply. Dualism, it seems to me, is just not in any way whatever phased with the duplication problem. And the answer to what constitutes my survival in heaven is very simple. I exist as a mental substance and I go on existing and for a while I’m not in heaven and then I am in heaven.
Cliff Williams: Can I ask a question about that mental substance? Do we have more time for this?
Chris Firestone: We have about five minutes left. Maybe one more question for each of you.
Cliff Williams: Is this mental substance a person?
Keith Yandell: Yes.
Cliff Williams: Now that strikes me as something contrary to our everyday conception about what a person would be, and also contrary to the biblical conception of a person. You’re at the intermediate state, so-called, the time between death and the resurrection. According to dualists, in the intermediate state there’s just the soul. Well, it seems to me that dualists have to say one of two things. Either the soul is the person, the sum and substance of the person, which Professor Yandell has said, or it is a truncated person. If it is a truncated person, then at the resurrection, the soul and the body are going to be reunited, and we get the whole person. But Prof. Yandell is not holding to that position.
Both of those positions strike me as counterintuitive and contrary to biblical evidence. According to the Bible, what we’ve got is a picture of people, I’m going to use the word holistic here. This is the not just the psyche, but a whole person. So to say that the mental substance is the person doesn’t fit. And the dualist who says that the soul is a truncated person is really paying a high price, which a materialist doesn’t have to pay. This came out in Professor Yandell’s remarks about the resurrection. Let’s see if I’ve got this right. Maybe you can answer yes or no to this. In the resurrection we’ve got a whole person to which is added a body.
Keith Yandell: If you really want to know my view, my view is this. While dualists have done shockingly little to develop this point, I deny that the biblical teaching is holistic in your sense. But it is something like that. What dualists have shockingly ignored is the fact that according to the biblical data, it seems to me, the soul of a human person is a soul that has capacities and abilities for relationships and communications that are best exhibited in relations with embodied persons. The human soul flourishes best embodied, and it is different in that respect from other substances. I grant you that dualists have been shocking in their lack of development of that point, and it has laid them open, or to appear to be open, to criticisms which are not inherent to the position, but to criticisms which are appropriately directed at a lack of dualists developing this thesis.
Let me ask you a question in the meantime. The Christian doctrine of the incarnation entails, I mean, asserts, that Jesus Christ was perfect God and perfect man. One person, albeit two natures. According to materialism, the human person is identical to a human body. Clearly, God the Son is immaterial. God the Son is a spirit. How can one possibly give a logically consistent account of the doctrine of the incarnation in materialist terms without maintaining the impossibility that an immaterial person has become identical to a material person?
Cliff Williams: Materialists have two answers. Number one: the case of Jesus is different from the case of other persons, in that every other person is purely material. In the case of Jesus, we’ve got an immaterial deity residing in something material. That’s one possibility. The other possibility is that divinity is exemplified in sinlessness. Materialists don’t find any difficulty in thinking of brains acting, thinking, feeling, praying, choosing. And those are the sorts of things that will either go toward sin or toward sinlessness. I think I better stop there.
Chris Firestone: Okay, now it’s time to hear from you folks. I think we have a pretty good analysis of the positions given the time constraints. Is there anyone out there who has a question?
Student 1: The question’s probably more for Dr. Williams, but really either of you. I feel like a lot of the discussion has focused on the resurrection and the afterlife in terms of heaven. But how would Christian materialism in particular look at hell, or would it have a conception of hell?
Cliff Williams: Well, thanks for that really good question. I don’t think Christian materialists think about that too much. And I haven’t. I think probably what I have to say is that it’s the same as for heaven. It’s re-created persons who are being punished. We’re talking about the metaphysics here, and what we’ve got is something physical that’s thinking and feeling, and feeling pain in heaven. That sort of thing. So I would just go for an analysis that’s analogous to what heaven would be, but, of course, the opposite types of experience.
Keith Yandell: My account is that if you go to heaven, on the materialist account, the good news is that somebody very like you is going to make it, someone very like you is going to be there, and the bad news is you’re not. And regarding hell it’s just the reverse. Careful copies, closest continuers, and the like, are copies. They aren’t you.
Student 2: My question is primarily for Dr. Yandell. I’d like to know how you view the soul. Do you view the soul as something that is constant and totally unchanging, or does the soul change as a person progresses through life?
Keith Yandell: The soul changes.
Student 2: The soul changes?
Keith Yandell: That’s perfectly compatible with being nonmaterial.
Student 2: Now if materialism, if one of the things that’s against materialism, is that you cannot establish identity of the body, because of the fact that it changes, then how do you account for the fact that the soul is the same thing, but the soul is also a changing thing?
Keith Yandell: I don’t at all find it a problem with materialism that things change. After all, I’m a dualist. I think there are material substances, and they change a lot. So change presupposes identity.
There’s a very strange idea in the history of philosophy—that change and identity are incompatible. But as Aristotle and Kant, among others, pointed out, change is a matter of something gaining a property that it didn’t have or losing a property that it did. So if change occurs, there’s got to be something that remains constant. The distinctive feature of some worldviews, like a typical kind of Buddhism, is that there’s an absolute denial of change. In that view it’s just flat out replacement. One state comes and then it vanishes, and another one replaces it. But change requires continuity over time, requires that the same thing exists throughout the process of change. Material things change relative to the type of properties material things can have, and minds change relative to the kinds of features that minds can have.
Student 3: I assume that on the materialist view the soul is material parts of the body. My question is about moral responsibility. In dualism my soul has moral responsibility to make choices that are good. Materialism looks like just the chemistry of the bodythe mind or something is produced by action or choosing of my brain. How can moral responsibility be tied to material things? It is something more than the chemistry of my brain. It’s very hard to find moral responsibility in materialism, because we would be made up only of atoms.
Cliff Williams: The materialist response here is that there is parity. Number one: the materialist view is that brains think and feel, and if you believe in free choice, then brains have this free choice. The Christian materialist view is that God is capable of giving brains the ability to feel and think and choose, and once you’ve got those you’ve got moral responsibility. That’s the first point.
The second point in this claim about parity is that it does not explain moral responsibility to postulate the existence of a nonmaterialist substance. That is just as mysterious as asserting that the brain has moral responsibility or that it can think and feel. What do you gain as a Christian dualist by postulating a nonmaterial substance? It has no more explanatory power than brains, it has no explanatory power. If it’s a mystery how brains think and choose and how we have moral responsibility, it’s also just as much a mystery how nonmaterial substances think, feel, choose, and have moral responsibility. God, after all, is capable of creating nonmaterial substances—souls—that have these capabilities. And God is also capable of making brains that have exactly the same capabilities.
Student 3: In biology we know that human cells totally change in a certain period of time. If that’s the case, then the material parts of my body, which are my personality, would change, and I would be somebody else, because all the atoms in my body, which were there a year ago, would be discharged.
Cliff Williams: I’m not sure that’s any more of a difficulty for the materialist than it is for the dualist. Prof. Yandell was just talking about change. The real question is duplication beyond the grave. That’s where we have opposite intuitions. But if you’re talking about change, the change of atoms in the brain, sure, it’s a known fact. I think it’s every seven years that all the cells or all the atoms in the body change. But clearly we’re the same. In some sense we’re the same. In some sense we’re not the same. So that’s no objection to materialism any more than it would be an objection to dualism.
Student 3: [Question about replacement]
Cliff Williams: Why is that a problem?
Student 3: Because I’m not more than I was seven years ago. The old atoms were replaced, and they are not part of my body anymore. They were totally replaced, and new atoms came into us.
Cliff Williams: You’re clearly the same person as you were seven years ago, at least in some sense.
Student 3: In the materialist view, I’m not, because all the atoms from my material body have been discharged.
Cliff Williams: Well, that’s not the criterion of identity for materialists. Materialists, as far as I can tell, typically adopt similar sorts of identity criteria as dualists do. I guess I’d like to ask Prof. Yandell another question. What is the criterion for identity in the dualist’s position? Here’s my point. It seems to me that the identity criteria involve personality patterns, the sorts of things that we identify as desires and basic drives. The dualists would use the same sort of thing. It seems to me that the nonphysical substance is entirely irrelevant to determining identity. And no materialist is bothered by the fact that we change. That’s not the criterion of identity. If I ask you what makes you the same now as when you were eleven, for instance, you would tell me that you have some of the same personality characteristics, talk pretty much the same, you have some of the same ideals. Those are sorts of answers that introductory students commonly give, and they are independent of whether or not dualism is true. Somewhere in there I had a question.
Keith Yandell: Let’s distinguish between metaphysical identities in nature and epistemological identities. I can make the distinction very easily. Two things [holds up two pieces of chalk]: let’s suppose that both are the same except that one has scratches on it. This is lefty. This is righty. [Puts them behind his back, then brings them out front.] Okay. Is this lefty or righty? I don’t know and you don’t know. The question, “Is this lefty?”, I don’t know. Here’s something we do know. One of these things is lefty and the other of them is righty. And they’ve retained identity between the time we started and the time that is right now.
Now what makes them the same is metaphysical identity. And what we’ve been talking about is metaphysical identity. It seems to me that on any materialist’s criterion of identity of a body, you’ve got to tell a complex story. For you to have the same body on a typical materialist account, you’ve got to have continuity. And these days typically materialists don’t want to talk exactly about the identity of a body over time and make that primitive. What they want to do is to talk about a material life. So long as you’ve got the same material life over time, and it’s the right kind of life, you’ve got a personal time. So in what seems to me to be the most interesting version of contemporary materialism, it’s material life that’s the primary criterion, and bodies are simply particles caught up into that life. It’s the same body so long as you’ve got the same material life, which is, of course, subject to the difficulty we’ve already talked about and that we’ve already noted that idealism and dualism are in fact not subject to.
What’s the story about metaphysical identity for a dualist or an idealist? It’s a very simple and straightforward one. What it is to be a person is to be a self-conscious mental substance. That’s what it is to be a person at a time. How does one differ from another in terms of their properties? If you want that account I’ll be happy to give you that account. Those of you taking my class tomorrow will see that account in painful detail [laughter], I mean, in pleasurable detail. What makes the same person the same self-conscious substance over time?—that you started out as a self-conscious substance and you stayed in existence. So the metaphysical story is quite simple.
Now how do you tell if it’s the same person? The reason I wouldn’t give a yes or no answer to my disappearing colleague is that I don’t know. My guess is that if that were to happen, he would’ve somehow become invisible for a while. But the very point is that the description doesn’t give you enough metaphysical detail to give you an answer. And so if I give the answer that I’m implying to give, without my reason being able to give that answer, it’s going to look like, though it’s completely false, that I think there’s any plausibility whatever in the view that something exists, altogether ceases to exist, and then exists again.
There are possible implications in which visible stuff becomes invisible for a while and then becomes visible again. I want to know metaphysically what’s going on in the disappearance case. Tell me that and I’ll tell you whether the same person’s around at the end. But anyway, that’s my answer to the metaphysical identity question. A person is an essentially conscious and equal or subconscious immaterial substance, and that’s what a person is at a time. Over time, you’ve got the same one, as long as it just keeps existing. It doesn’t have to do any neat things, it doesn’t have to play violin or learn new music. It just has to continue existing.
Student 4: I was wondering if you have an account of mind-body, soul-body, interaction.
Keith Yandell: Sure. Minds affect bodies and bodies affect minds. The idea that this is somehow a problem is one of the grand superstitions of philosophy.
Cliff Williams: And I concur. We agree! I think dualism is a possible position.
Keith Yandell: The only time in philosophy that anybody still brings up the objection that mental events cannot cause physical events, and physical events cannot cause mental events, because they’re so different, which really requires the premise that A can cause B only if A resembles B, the effect in certain respects resembles the cause—the only time the causal-resemblance theory is ever brought out in contemporary philosophy is to try to support this age-old “difficulty” with dualism. That, Descartes answered perfectly well.
Suppose John has been courting Mary for 39 years, terrified of commitment. Finally John wakes up and says, I’m going to do it, calls Mary and asks her, “Mary will you marry me.” Mary faints from shock. Well, where’s the resemblance? What was it in John’s making that crucial phone call that resembled Mary’s shock?
The most interesting version, by the way, of the objection sort of behind your question that I know of is discussed in a book edited by Kevin Corcoran. The title of it, since it’s fairly similar to Cooper’s title, escapes me, but it’s a 2001 book published by Cornell University Press [Soul, Body, and Survival: Essays on the Metaphysics of Human Persons], edited by Kevin Corcoran. There’s an article by E. J. Lowe [“Identity Composition, and the Simplicity of the Self,” 139-158]. Lowe argues that minds cannot affect bodies unless they’re spatially located. The view is more complex than that, but that’s the focus of it. Tim O’Connor [“Causality, Mind, and Free Will,” 44-58] replies to Lowe. I don’t think we’ll argue his [Lowe’s] view, but it’s at least a new objection and not just the old mental stuff and physical stuff are so different they can’t causally interact. I mean, I’ve got a cold. The cold bacteria don’t resemble the ache in my chest or my cough.
Chris Firestone: I’ve got one last question. It’s kind of a summary question and then we’ll be finished. I’m just trying to get my head around what’s been said so far. Prof. Yandell, if I understand your position correctly, it’s that the metaphysical continuity thesis cannot be maintained if you instill in the position annihilation at some point. You can’t have both of those two simultaneously. Even God can’t maintain metaphysical continuity. It’s a logical contradiction of terms.
Keith Yandell: I wouldn’t want to put it that way. There’s no reason God couldn’t create the moon and keep the moon in existence absolutely forever. My argument is simply that either materialism of the kind we’ve discussed—there are still other kinds of materialism, we haven’t gotten to them—but the kind of materialism we’ve discussed and the view that what a person is, is just a sequence of mental states, both entail that something is possible which is impossible, namely that one thing would have to be identical to two things which are not identical to one another. But I’m not at all claiming that God can’t sustain material bodies in existence for however long God wants to sustain them in existence, including everlastingly.
Chris Firestone: But if they go out of existence, then they cannot come back as the same.
Keith Yandell: Right.
Chris Firestone: Just by definition that’s not possible. Prof. Williams, why does metaphysical continuity matter for Prof. Yandell?
Cliff Williams: My example shows I think that it’s not important. Intuitively we’d say it is the same person. Also, God is going to resurrect bodies. They’re the same, and they don’t require metaphysical continuity. In general, what I want to say is that these questions of identity are controversial. They require discussion, and it’s not clear to me that dualists should hinge their belief in dualism on a principle that’s controversial with respect to Christianity.
Chris Firestone: I want to thank both professors for joining us. Let’s give them a big round of applause.