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How Could Anyone Be a Dualist?

Dean Zimmerman

Opening Statement

In theological circles, “dualism” is a dirty word. “Dualist” works sort of like “reactionary.” To be a reactionary isn’t merely to be a political conservative; it is to be a knee-jerk conservative — someone who resists even reasonable, moderate reforms. Likewise, to be a dualist isn’t just to be someone who draws a distinction between two things; it is to be someone who draws a sharp distinction where there isn’t one, someone who divides the world into two very different categories when these categories don’t apply or are not exhaustive. So, when “dualism” is used as a term for a view about the nature of human beings, it nowadays often means: “an extreme Platonistic division between body and soul that is scientifically untenable, alien to Biblical religion, and morally pernicious.” The Platonizing dualists for whom this label is reserved think that the soul is naturally immortal. They hold that it is better off without the body, which only drags it down into sin and clouds its ability to think. They expect that, after death, we live on as souls in heaven, happy forever in a disembodied state (a heresy according to every major strand of the Christian tradition, all of which emphasize the resurrection of our bodies as a crucial part of the life of the world to come).

If “dualism” is freighted with all of this Platonistic meaning, I am not a dualist. I do draw a distinction between soul and body; but I do not think souls are naturally immortal, that they are better off without bodies, or that — in the absence of a miracle — they can think without brains. Like Paul, other New Testament authors, and indeed Jesus as depicted in the Gospels, I expect that a person exists in a disembodied form after death. But, like them, I deny that this is the natural, permanent state for which we were made. Rather, death is only really defeated by the resurrection, the reunion of soul and body. I do not believe that such a view of persons is refuted by the discovery that thinking and personality are radically dependent upon the brain; nor do I believe that those who hold this sort of view will inevitably be led to denigrate our bodily life or to destroy the fragile eco-system of our planet.

Philosophers often use the word “dualism” without all this Platonistic freight. So, when talking with other philosophers, I can call myself a dualist without fear of misunderstanding. But in other contexts defending my view as a kind of dualism is like trying to defend universal healthcare on Fox News under the label “socialized medicine.” Socialized medicine is socialism, which is communism, which is atheism, which is evil. Unfortunately it is hard to come up with a snappy alternative label in the case of dualism. Some who hold views similar to my own have tried to soften the blow with modifiers. The philosopher William Hasker talks of “emergent dualism”; the biblical scholar John Cooper talks of “holistic dualism.” For reasons Hasker has given (described momentarily), someone who regards the soul as the conscious part of a human being really should extend the honor to the other conscious creatures with brains like ours; in other words, there are human souls and animal souls. It is tempting to call this view “animism,” though the expression might suggest souls for trees and springs and rivers as well — and that, I expect, would be going too far. So I shall accept the label “dualism”, but jettison the excess baggage that is often attached to the word when used in theological disputes.

I begin by describing the kind of dualism I find most believable, and saying why I do not think it is just obviously false. Then I explain why traditional Christian views about what happens to us when we die seem to me to require a dualism along these lines.

Emergent Dualism vs. Standard Materialism

Dualism, as I shall be using the term, is the doctrine that no thinking human person is composed of the kinds of physical stuff that make up rocks and trees and the bodies of animals. Persons have thoughts and feelings and sensations, but we have little in common with either the physical objects that surround us or with their fundamental constituents (electrons, quarks, and so on). More familiarly, dualism is the doctrine that human beings have — or, much better, are — souls. Materialism, for my purposes, is the thesis that each human person is an object made entirely out of the kinds of physical stuff that make up rocks, trees, and other non-sentient things.

There have been many different views among dualists about the relations of souls to bodies; are souls completely dependent upon bodies, just along for the ride? Or are they completely independent, much better off when they leave their bodies behind? If souls are not particularly dependent upon bodies for their existence or sentience, do they have to be specially created each time a viable organism appears? And does God do this for animals too, or just for us? Are souls completely “outside of space,” not spatially related to locations in our space? If so, how can they interact with things here — in virtue of what relations between souls and bodies does my soul get hooked up with my body and not with yours?

It would fly in the face of experience to claim that my ability to think is not radically dependent upon the proper functioning of my brain. And it would also seem best to regard human beings as ontologically continuous with the rest of the sentient animal kingdom. All of this can be preserved by Hasker’s emergent dualism, according to which organisms having sufficiently complex nervous systems to generate consciousness automatically also generate a nonphysical substance located somewhere within the nervous system to be the subject of that consciousness — a substance which remains radically, but not completely, dependent upon the brain for most of its operations and for its continued existence (barring a miracle).

Souls, on this view, are “naturally emergent substances”: Given a certain microphysical structure — the kind found in the brains of sentient organisms — there must be a thinker associated with that structure. But the “must” here has only the force of natural law. It’s just part of the way things work. Since laws of nature could have been different, there are possible worlds with soulless zombies that are just like us physically. Assuming that souls do in fact interact with the brains that generate them, these zombies would not behave like us, since their brains wouldn’t be receiving whatever input ours normally receive from souls. Perhaps, cut off from souls, animals with brains like ours wouldn’t be able to do much of anything; perhaps they would be like the zombies of horror movies — still able to move around in search of food…for example, human brains!

Souls, on this account, have no parts in common with our bodies, so they are nonphysical in the sense of “not made out of the things physics now studies.” But, they could be spatially located for all that. They may even, as W. D. Hart suggests in The Engines of the Soul, be the possessors of a kind of “psychic energy,” interacting with the body by the usual method: transfer of energy. Hart’s notion of psychic energy is (among other things) a function of degrees of belief; it takes more energy to sustain a belief with a greater degree of conviction. Of course what Hart gives us is a just-so story, and I wouldn’t want to be committed to the details (and I don’t see why all causation has to be a matter of the transfer of energy continuously through space, as Hart assumes). Still, one can see how to pair a body with the appropriate soul — a brain interacts with the soul it generates inside of itself, a soul affects the brain in which it is located. And, as Hart shows, one can even imagine mechanisms for such interaction.

When assessing the plausibility of this sort of dualism, one must compare it to the best available materialist alternatives. There are forms of materialism that are stranger than the sort of dualism I have described. For instance, Descartes talked about madmen who believed they were made of glass — a materialistic doctrine with nothing to be said for it! Roderick Chisholm, no madman himself, once half-seriously defended the thesis that he was a tiny physical particle lodged somewhere in his brain. More popular, of course, are versions of what I’ll call “Standard Materialism”: a human person is identical with a familiar physical object that everyone already believed in, one that includes at least the parts of the body that are most crucially implicated in thought and personality. This leaves us with just a few candidates: the whole organism, the whole nervous system, the brain, the cerebrum, maybe one hemisphere. Standard materialism, then, will be the thesis that each human person, including myself, is one of these standard candidates. If there are problems with standard materialism, the only versions of materialism left are strange, hard to believe, and a modest dualism like Hasker’s begins to look like a viable alternative.

And standard materialism does have problems. Organisms and brains are vague things, not unlike rivers or clouds when one looks closely. They are buzzing with activity, constantly losing and gaining bits of matter by means of continuous processes — as when proteins pull molecules into cells to put them to work. Before the molecule is captured by the cell, it is not part of the body; once inside the cell it surely is; but exactly when does it become a part? Choosing a precise instant would be as phony as saying that there is a precise instant when a molecule of H2O joins a cloud, or leaves the Mississippi River to enter the Gulf of Mexico. These are matters for stipulation, and many choices are admissible. But if the stipulations are to work, there must already be all sorts of candidate objects, some including borderline molecules and some not, all of them ready to be picked out by our decisions. So long as we don’t care to become more precise, we speak indiscriminately about the whole host; and what we say about their current local properties — their sizes, shapes, weights, colors, and so on — is true so long as it’s true of each of them.

I find it hard to believe that I am a vague object, for which there are many equally good candidates. Each must be conscious, if each is as good a candidate for being me as the others. Now, if consciousness were just a certain kind of computation, it would be plausible to suppose that the host of objects located in the vicinity of my brain would all be conscious; after all, each has the brain as a part, and if it is essentially a computer they will be running the same program in virtue of sharing the same processor. But if consciousness is something more, a new and fundamental feature of the world that can’t be identified with any extrinsically specifiable physical process, then there is no reason to think that the laws of consciousness-generation will pick out exactly the candidates we are interested in — just those clouds of particles that are the size and shape of an organism or even a brain. So the materialist who admits that consciousness is something special, something that cannot be reduced to a physical process, should not expect any standard sort of materialism to be true.

Is consciousness so special? Almost all philosophers used to think so, and quite a few contemporary philosophers of mind still do. Believers in a God who can know what our experiences are like should agree. To know what colors and smells are like, one must be able to have some kinds of sensory experiences; so God can have experiences like ours and no doubt many others we could never have. In that case, conscious experiences can be shared by us and a mind that is not made of matter or any other kind of stuff. Having these conscious experiences cannot, then, be a matter of having an inner computer running a certain program; it is some further feature of minds.

A materialist who admits that consciousness is not reducible to some computational or chemical or biological process must suppose that, when brains are sufficiently complex, consciousness “emerges,” attaching itself to some object or other that is made entirely of physical stuff. It would be quaint to suppose that the laws of nature governing this new aspect of the world are careful to select objects of sizes and shapes that interest us; but what objects should they pick? Parts of the brain are the best candidates — being closest to the causes of consciousness — but which parts? Since different parts are implicated in different sense modalities and different kinds of conscious thinking, the best bet might be: many different parts at different times. Whatever choice the materialist makes, it should not be one of the standard candidates; and a rival, dualistic hypothesis belongs on the table: the idea that, with new properties there comes a new subject for those properties.

Dualism and Disembodiment

If this were the most that could be said for dualism, one should probably simply settle for what George Graham calls “Strong Ontic Ignorance”: the view that we can’t know exactly what kind of thing we are. But Christians (at least many of us) have special reasons to believe in the possibility of our own disembodied existence; and this should tip the balance, for us, in favor of dualism. In my own case, although I would not claim to know that dualism is true, I do have beliefs about the afterlife that I take to be reasonable; and, if they are true, dualism must be true as well.

Christians differ in their attitudes toward the authority of scripture; they endorse different hermeneutical methods, and adhere to different creeds and theological traditions. Some theologians regard a personal creator God, an empty tomb, and the general resurrection of the dead as primitive elements of the faith that can be discarded without touching the heart of the Christian gospel. They will be unmoved by the considerations I am about to raise.

It matters to me what Jesus and the writers of the New Testament believed about the nature of human persons and their post-mortem destinies. Why? Because it is relevant to the question of what they meant when teaching the earliest Christ-followers about life after death. John Cooper makes a powerful case for the conclusion that the earliest Christians accepted a kind of animistic body-soul dualism — a view that was well-established among the most pious Jewish sects in the intertestamental period. Cooper argues that the New Testament writers make this dualism explicit in the gospels and epistles, and that it shows up when important theological points are being made; so it cannot be easily brushed aside as window dressing. Even some of the biblical scholars most famous for emphasizing the distance between Jewish conceptions of persons and the Platonistic idea of a naturally immortal soul, such as Oscar Cullman and N. T. Wright, admit that Christ himself and the earliest Christians taught that the dead continue to exist. They are disembodied, to be sure, but they remain in some sense conscious of or present to God, awaiting reunion with a resurrected body at the end of the age. And that is enough for my purposes.

For the possibility of an intermediate, disembodied state requires a dualism — right now — of person and body; at least, it requires this, given some plausible assumptions about what kinds of changes things can undergo. If, right now, materialism were true of me, then my suddenly becoming disembodied — suddenly losing all my material parts, and becoming entirely nonphysical — would require that something could lose all of its parts at once and continue to exist made of other stuff. As Richard Swinburne points out in his defense of dualism, this hardly seems possible. Imagine an entirely physical thing that loses all its parts at once; the subatomic particles constituting it all suddenly wink out of existence, say. Now suppose that the instant these parts disappear, there comes to exist a thing that is in many respects very similar to it but made of some completely different substance. What one has just imagined is the replacement of one thing by another, not the persistence of the original thing. Adding consciousness to the two things will not make it any easier to suppose there is just one thing that persists through the change, even if they are mentally very similar.

The conclusion is straightforward: in order for me to continue to exist in a disembodied state, something that exists after my disembodiment must already be around, and it must at least be a part of me. Furthermore, since, when I am disembodied, that thing is going to be all of me, it is then going to have to be identical with me. And the following is a philosophical truism, something that is pretty obvious when you think about it: once you’re identical with a thing, you’re always identical to it. That’s just the way identity works. If Pastor “Jack” Gibson of San Francisco is identical to Jack the Ripper, then whatever’s true of Gibson must be true of the Ripper. If Jack the Ripper dies, so does Jack Gibson, and vice versa. So if I will be identical with a nonphysical thing that survives my body’s destruction, I am already identical with it. Strictly speaking, then, this gross physical body is not even a part of me, though it may be essential to my origin, and physically necessary for my ability to think and feel, at least as things are now.

Of course some Christian scholars, sometimes precisely to avoid this sort of result, are skeptical about whether human beings exist during a period intermediate between death and resurrection. But when I find the doctrine clearly affirmed in places where the New Testament writers are trying to convey deep theological truths, I am reluctant to give it up — barring powerful scientific or philosophical arguments against it. And, so far, I haven’t found such arguments overwhelming. Most are aimed at highly Platonistic views, according to which souls are outside of space, naturally immortal, or able to think better without brains than with them. None of those doctrines seem at all relevant to the things that make dualism attractive to me. Other arguments proceed in this fashion: There is no obstacle to attributing consciousness to physical objects we are already familiar with, such as organisms or brains; therefore there is no reason to suppose that some peculiar new entity is the locus of consciousness. But organisms and brains are vague, and our interest in them is parochial; we should not suppose that the phenomenon of consciousness is bestowed upon them, for reasons I mentioned. Human persons are either peculiar physical objects, or something entirely new in the world — something that appears whenever consciousness does. The latter hypothesis has this going for it: it is required by a doctrine that seems to me to be central to Christianity. So I remain strongly inclined towards dualism.