The Table Video

Richard Swinburne (Oxford University) and Tim O’Connor (Baylor University) discuss neuroscientific research that purports to disprove human freedom; each suggests why his view of the human person is consistent with libertarian freedom.

Transcript:

The French neuroscientist Benjamin Libet did certain experiments in the 1980s, which other neuroscientists generalized to show, which they suggested showed that never do our intentions, purposes make any difference to what we do. What we do is controlled just by brain goings on, and we think we have formed an intention and that’s why we do something. But really it’s just brain goings on that make this difference.

And the evidence which was brought forth for that by generally the followers of Libet, was that they found that whenever somebody does an intentional action, decides to move their hand or decides to go for lunch or something, there is always some build up of electrical potential on their skull, which indicates some brain going on.

And many neuroscientists say that happens before the subject forms any intention to go to lunch, or any intention to wave their hand. And so many neuroscientists said oh well what that shows is that the brain event causes the motion of the hand and that the intention has nothing to do with it. But of course all that the experiment showed is that equally compatible with the experiments or results would have been that the original brain event causes the intention and the intention itself causes the motion of the hand.

Well, neuroscientists could try and do some more complicated experiment, which might show that the motion of our hands was simply caused by bodily goings on. But I don’t think they could ever show that our intentions don’t cause that. Though, in some few cases, they might show that we are compelled by bodily, brain goings on to form an intention.

But I see no reason to suppose that to be generally the case because all that neuroscientists throws up is information about the inclinations, the desires to which we are subject. And we all know that when faced with a choice worth acting on some desire or yielding to temptation, it’s up to us what we do. And nothing neuroscientists have shown has any inclination to show that is isn’t in those cases.

So on this view, dualism actually helps preserve free will in a way that otherwise free will might be brought into question.

Yes, I don’t think dualism is necessary for holding a doctrine of free will, but it certainly helps to bring out what is involved with it. Needless to say that what determines our actions is what we determine our action, and we determine our action in the light of reasons and desires to which we are subject. Intuitively we know, or think we know, that’s how things happen. And nothing that any neuroscientist has produced shows that it isn’t.

And Tim, I know you’ve been concerned to defend a version of free will as well. Do you think that your emergent view helps with the free will question, vis a vis substance dualism?

I believe it’s as compatible as substance dualism is with the view that we exercise a limited measure of autonomy.

We are not perfectly free beings, we are constrained. As science shows, not just neuroscience, but shows through psychology we’re often subject to unconscious influences. So it’s a constrained freedom of will but I think we do have sufficient freedom that we can be held morally accountable for our choices. It’s a common place that the popular press often does a very poor job of reporting scientific findings.

And I agree with Richard that in some cases the scientists themselves are a source of the problem, insofar as they put philosophical glosses on their findings that go well beyond their findings. They’re putting an interpretation on their findings that the results themselves hardly imply. Although, they might be compatible with the findings.

And so, I agree with Richard that it’s often overblown. Some of the interesting things that are being learned about how the brain functions. But, we should recognize that the science of the brain is still in relative infancy, or maybe in its adolescence you might say at this point. Before the 1950s, very little was known about the details of brain function, and now scientists seem to have a very good handle on how individual cells of the brain, neurons interact, transmitting chemicals across synapses and that sort of thing.

But how large scale assemblies of neurons are involved in the production of complicated bodily behavior, let alone conscious choices, is still not well understood at all. There is a differentiation of function, scientists have been able to identify different regions of the brain being associated with different functions, like the visual cortex and the auditory cortex and so forth, but most of the really crucial details about how complex behaviors produced are still wide open.

And I agree that the Libet findings just show that there’s activity, a kind of preparatory activity perhaps, where we know we’re about to… And we have to think about the Libet scenario where you’re being invited to engage in a specific behavior, such as wiggling your finger, within a short interval of time and then you’re just asked to spontaneously decide when you will engage in that behavior. And there should be some sort of anticipatory brain activity to enable a smooth carrying out of that behavior when a choice is made, is not terribly surprising, right.

We don’t know a sensible view, whether a substance dualism view, or my sort of view, or even on a materialist view. No view do choices just come out of the blue quite apart from any antecedent influences. So, yeah, I think I do want to have a view on which we have capacities to make choices that don’t reduce the physical capacities.

And that we consciously control that capacity, at least in many circumstances, when we’re fully in control of our faculties and we’re aware of real options available to us, and I think that’s wholly consistent with the findings of neuroscience.

Yes, all that the neuroscientists have discovered in more detail about the goings on in the brain before we make decisions… [stuttering] They may have established a correlation between certain goings on and say, the subject moving their hand, but the correlation is not 100%, it’s 80%, or 75%, that is to say that indicates that what they’ve discovered is an inclination to do it to which eventually the subject may or may not decide to follow.

But, one point about neuroscience I wouldn’t altogether agree with you about individual neurons. Sure, what is known is that the brain is a large collection of neurons and each neuron transmits an electrochemical influence to the next neuron. But how it does this by releasing a small amount of transmitter substance which clings to the next neuron and starts an electrical pulse passing through that. But whether it does this or not just depends on just how much transmitter substance is released and just how wide the gap between the two neurons, the synaptic cleft is, and just what happens to each bit of transmitter substance that’s released.

And these are goings on on a very very small scale, and such literatures I have read is certainly favorable to the view that these goings on, whether enough transmitter substance is released at the cleft in order to start an impulse passing through the next neuron, depends on such small differences that these differences lie within the quantum limit.

That is to say, the great physical theory of the 20th century, quantum theory, is an indeterministic theory. It says that on the smallest of small scales you can only talk about probabilities of things happening, not about inevitabilities of things happening. And the scales involved in the transmission of electric charge from one neuron to another are on that very small scale so that whether potential is transmitted does depend on something within the quantum limit and is therefore not predetermined.

Of course, it is logically possible that these… That these very small differences in one neuron isn’t gonna make a very great difference to the large scale behavior. On the other hand it may make a very large scale difference to our behavior, that isn’t known. But there is undoubtedly a certain amount of indeterminism in the brain so it would be perfectly compatible with all we know about the operation of the brain to suppose that some of its operation is not determined by physical laws.