Does Brain Science Disprove the Soul?
Richard Swinburne (Oxford University) and Tim O’Connor (Baylor University) weigh substance dualism on the scales of contemporary neuroscience—how does the existence of the soul comport with empirical neuro-research?
So Richard, Tim has suggested that his view, this emergent view comports with contemporary neuroscience and some might think that substance dualism is in trouble when it comes to contemporary neuroscience because these things that we used to think that the soul was responsible for, we’re finding out that the brain is responsible for. So how do you respond to this idea, that we have kind of a soul of the gaps response, that we don’t need the soul any more given what we understand about the brain?
Well I’ve given that a straight philosophical argument for existence of the soul, so your point is that it doesn’t fit with contemporary neuroscience. Well, I don’t see that at all. I’ve no objection to any particular detailed result that contemporary neuroscience has made.
Quite clearly we are influenced, our choices are influenced by goings-on in the brain, but this isn’t news. We’ve always known that humans are influenced in their choices by physical goings-on. It’s well-known that if people haven’t eaten for 24 hours they feel hungry and they are inclined to eat. This has been known for millennia.
All that neuroscience has done has been to add a lot of further bits of information of that sort. Neuroscience has told us the mechanism by which lack of food causes the desire to eat, and neurosciences has pointed out other mechanisms that are at work causing desires, but neuroscience has never shown whether, which persons will inevitably act on the desires to which they are subject.
We have a choice of whether to act on one desire or another, whether to do what we believe good or to yield to a temptation to do what is evil. And no result of neuroscience has shown that we can’t do that. Some results, or rather some statements of neuroscientists about what they have achieved, seems to be a manifestly false account of what in fact they have achieved.
To go back for a moment to neuroscience and the existence of the soul, Tim, Richard made the claim earlier that no amount of contemporary neuroscientific evidence is going to show that there isn’t any such thing as the soul, understood in a dualist sense. Do you agree with that, and then if so, how is it then that you made the claim earlier that you think this emergentist view comports better with biological evidence including neuroscientific evidence?
Good, I think I probably agree with Richard that neuroscience is at any rate unlikely to demonstrate non-existence of the soul understood as a purely mental substance. Scientific theorizing is always a matter of putting in interpretation, trying to put the best interpretation on observable facts. It doesn’t usually proceed by way of outright demonstration of truths, it’s just certain theories seem to prove more fruitful and more predictively powerful than other theories, and therefore we run with them until better theories come along, and new data that need to be accommodated.
So in a nutshell, if you’ve been comparing our views, there’s been a strong agreement on that our mental lives do not reduce to our physical lives, so what difference does it make? From my view, new capacities emerge, think about the development of a living organism, our bodies. We have a lot, if we are fully intact functioning adult human beings we have a lot of sophisticated cognitive capacities, and affective capacities of emotion and desire and so forth.
As I understand the dualist view, one would have to suppose if the soul emerges or appears in the very early stages of embryonic development, since the soul has no parts, its not a composed object, all of its basic capacities are there from the get-go, and then as the brain matures some of those, many of those capacities are completely latent, young infants can’t do calculus, right.
But as the brain matures, then what the soul is capable of doing and engaging in thought now becomes activated, the necessary physically causal conditions on it. That’s a possible view, but it suggests kind of an abrupt break, so you have a very immature organism that is associated with something that has these potentially quite complicated functions already fully intact, rather than on my view, the mental capacities, since they are capacities of the organism, develop in tandem with the development of the organism. And that just seems to me to be a more natural interpretation of what we know about organism development.
One point I would, one stage in your argument seems to be mistaken. You’re arguing from the fact that the soul has no parts, to the fact that it can’t grow in its capacities. But I don’t see that follows at all. Capacities are properties of a thing, and a thing can acquire many extra capacities even if these all belong to one part, so I don’t follow that stage of the argument. But, more substantially, it seems to me that any theory which says that there is a sharp break has a lot more to be said for it than any theory that says there is a gradual evolution, because you took the fetus developing into the child, but if we take for example the gradual development of the human race from inanimate matter over time, four billion years ago nothing had any feelings or thoughts.
Now we have lots of feelings and thoughts. So some time or other there must have been a first feeling or thought. Some mental event that the subject was aware of and to which he had privileged access, to which, of a kind that had never happened before. That seems to me inevitable. Because once upon a time there weren’t any such things and now there are such things, there must be a first time at which such things appear. Now of course we don’t know what that time is.
My argument is compatible with the higher animals having thoughts and feelings, and therefore by my argument having souls, but who knows, nobody knows, whether ants have feelings, or whether fish have feelings. I’m inclined to think that only mammals have feelings, but there comes a time, a sharp time, and if a theory says there isn’t a sharp time it seems to me it hasn’t grasped the very nature of the mental which is so different from the physical, it’s something to which the subject has privileged access.
And, the moment there is a being who has mental events, has thoughts and feelings to which he has privileged access there is someone who has these thoughts and feelings, and it’s a fact about the world that that individual had them rather than any other individual, and given that, and given that the body doesn’t carry the identity, because I could have a different body, it must be another part of me that has that identity, so the very emergence of consciousness must bring with it a soul, and that’s how it is.
There is this sharp break in evolution, because something has appeared that simply wasn’t there before. And if some evolutionary theory tries to show that there isn’t a break then it must be mistaken, for this reason, the facts are just, stare one in the face on this matter.