Zombie Neuroscience

October 14, 2014

In an opinion piece in the New York Times Sunday Review (October 12, 2014, p. 12), Michael Graziano asks “Are We Really Conscious?” His answer is that we are probably not conscious. If his theory is right, our belief in awareness is merely a “distorted account” of attention, which is a reality that consists of “the enhancing of some [neural] signals at the expense of others”.

This distorted account develops in all of us, and seems to us to be almost impossible to deny. But beliefs that the Earth is the center of the universe, that our cognitive capacities required a special creation, and that white light is light that is purified of all colors, have seemed quite natural and compelling, yet have turned out to be wrong. We should be skeptical of our intuitive belief that we are conscious.

In short, Graziano is saying that your impression that you are conscious is likely a false belief. “When we introspect and seem to find that ghostly thing –awareness, consciousness, the way green looks or pain feels – our cognitive machinery is accessing internal models and those models are providing information that is wrong.”

One might well wonder what is supposed to be “ghostly” about the experience of green you think you have when you look at, say, an unripe banana, or a pain that you might believe occurs when you miss a nail and hit your thumb with a hammer. But, of course, if you are already convinced that there are no such things, then you must think that their apparent presence is merely the holding of false beliefs. If you then try to say what these false beliefs are beliefs about, you will be hard pressed to produce anything but ghosts. There are, of course, neural events that are necessary for causing these allegedly false beliefs about the way bananas look or pains – but these beliefs are not beliefs about those neural events, nor are they beliefs about any neural events at all. (People believed that unripe bananas looked green and that they had pains long before anyone had any belief whatsoever about neural events.)

Graziano’s positive story about awareness is that it is a caricature: “a cartoonish reconstruction of attention” (where, recall, attention is enhancement of some signals at the expense of others). This description raises a puzzle as to what the difference is between a cartoonish reconstruction of a signal enhancement that is caused by light reflected from an unripe banana, and a cartoonish reconstruction of a signal enhancement caused by a blow to your thumb. But perhaps this puzzle can be resolved in this way: The banana causes enhancement of one set of signals, the blow to the thumb causes enhancement of a different set of signals, and which false belief you acquire depends on which set of signals is enhanced.

A problem remains, however. Your beliefs that you are experiencing green or that you are in pain are certainly not beliefs about your signal enhancements. They are not beliefs about wavelengths or neural activations caused by blows to your thumb (though, of course, wavelengths and neural activations are among the causes of your having beliefs about what colors or pains you are experiencing). There is nothing else relevant here that Graziano recognizes as real. Your false beliefs are beliefs about nothing that is real.

We can, of course, have beliefs about things that are not real – for example, unicorns, conspiracies that never took place, profits that will in fact never materialize. In all such cases, however, we can build the non-existent targets of the beliefs by imaginatively combining things that do exist. For example, we have seen horses and animals with horns, so we can build a horse with a horn in our thoughts by imaginative combination.

But green and pain are not like unicorns. They have no parts that are not themselves colors or feelings. There are no Xs and Ys that are not themselves colors or feelings, such that we can build green or pain in our imagination by putting together Xs and Ys. So, if we were to accept Graziano’s dismissal of color experiences and pains as unreal, we would have to allow that we can have beliefs about things that neither exist, nor can be imaginatively constructed. We have, however, no account of how there could be such a belief. The words “way green things look” and “pain” could not so much as mean anything, if we suppose that there are no actual examples to which these words apply, and no way of giving them meaning by imaginative construction.

Graziano invokes impressive authorities – Copernicus, Darwin, and Newton – in support of skepticism about intuitions that once seemed incontestable. (See list in the second paragraph above.) He presents his theory as coming from his “lab at Princeton”.

The view he proposes, however, is not a result supported by scientific investigation. It is supported by the other authorities to which he appeals – Patricia Churchland and Daniel Dennett. These writers are philosophers who offer to solve the notoriously difficult mind-body (or, consciousness-brain) problem by the simple expedient of cutting off consciousness. Voilà. No more problem.

But it is not good philosophy to affirm a view that commits one to there being beliefs of a kind for which one can give no account.

It is important to understand that resisting the dismissal of consciousness is fully compatible with affirming that there are indeed neural causes for our behavior. Hammer blows to the thumb cause neural signals, which cause reflexive withdrawals. Somewhat later, the interaction of these signals with neurons in our brains causes behaviors such as swearing and taking painkillers. But hammer blows to the thumb also cause pains. It is indeed difficult to understand how or why pains should result from neural events that such blows cause. But it is not a solution to this problem to dismiss the pains as unrealities. Nor is it true that science teaches us that we ought to deny consciousness.


Is There an Appearance/Reality Distinction for Pain?

January 23, 2012

In a recent article, philosopher Kevin Reuter has provided an interesting example of experimental philosophy that challenges a widely held view.

The background is that many philosophers (including me) hold that there is no appearance/reality distinction for pain. Pain is nothing but a feeling, so if you have a painful feeling there is no question but that you have a pain. You can be fooled about what is causing you to have the pain; for example, you might think you’ve got a tumor when it’s just a cyst. But you can’t be fooled about whether you are suffering. (Another author in the same journal humorously imagines lack of success for a doctor who would refuse to prescribe painkillers, explaining that the patient is only having an appearance of pain, not a real one.)

There are parallels for our “outer” senses. You can, for example, be fooled about what color a thing is, because you might be looking at it in bad lighting. But you can’t be fooled about the way it *looks*. You might inadvertently pick the wrong word for the color a thing looks to you, but hardly makes sense to say that a thing might seem to look to you other than the way it does look to you. The way a thing looks just is its appearance, and while things in your kitchen can appear other than they really are, appearances themselves can do no such thing.

Many leading views say that the same thing holds for pain. There is simply no difference between feeling a pain, or having something appear to you as a pain, and actually having a pain.

Many leading philosophers also believe that this view – “There is no appearance/reality distinction for pains” – is not a philosophical theory. They are not claiming to say what people *ought* to believe about pains and they are not claiming to have made a philosophical discovery. They regard themselves as merely making explicit what is already implicit in the way people in general speak about their pains.

It is this attribution to the general public of the “No appearance/reality distinction for pains” view that Reuter directly challenges.

The key ground for the challenge is something one does not often see in a philosophy paper. It is a statistical analysis of remarks by non-philosophers – in this case, remarks found on health-related internet sites. Reuter gives details about his methods of search and analysis, but I will just summarize the key results, which I think his evidence clearly supports.

To wit: (1) People use both “I feel a pain” and “I have a pain” (and grammatical variants) in reporting both mild pains and severe pains. However, (2) “feel” is used about as often as “have” when mild pains are referred to, whereas “have” is used far more often than “feel” when the reported pain is severe (about 6 times as often on average, ranging from equally often to 14 times as often, depending on exactly what word — e.g., “major” , “severe”, “bad” — is used).

Result (2) is then combined with another observation: When people use variants of “seems” (e.g., “feels” “looks”, “sounds like”, etc.) in the case of senses such as touch, vision, or audition, they are making an appearance/reality distinction, and they are indicating lower confidence in their judgment. For example, if you speak of a blue tie, or say a tie is blue, you are confidently committing yourself to the claim that the tie is blue. But if you say it looks blue, you are leaving open the possibility that it might not really be blue, and that the way it looks – its appearance – is misleading as to how it really is.

The conclusion is then drawn that the difference in frequency of use of “feel” versus “have” that correlates with mildness versus severity of pain indicates that, at least for mild pains, people – users of health-related internet sites – are making an appearance/reality distinction.

Of course, this conclusion depends on supposing that there is not a better explanation of the correlation between “feel”/”have” and mild/severe. Reuter considers several more or less plausible alternative explanations, and adequately rebuts them. The most plausible of these is that “I have a pain” is, implicitly, a request for help. If the pain is mild, there may be no need for help, so the person reduces the help-seeking implication by using “feel” instead of “have”.

Reuter’s point about this suggestion is that more direct means of seeking aid are easily available, so it is unlikely that pain reports have the function of indirectly asking for help.

There is, however, a variant of this alternative that Reuter does not consider. People know that others are likely to empathize with a reporter of pain. So, if the pain is mild, the person who reports it may want to convey something like “Don’t worry, don’t feel bad for me, it’s only a little pain”. Perhaps using “feel” is a way of indicating this lack of need for empathy.

Of course, it’s unlikely that anyone thinks explicitly that this is what they are doing. So, we might wonder whether such an unconscious adjustment of language is too subtle to be plausible. I do not think so. Consider the shades of politeness in the following list:

Shut the door.

Shut the door, ok?

Would you shut the door?

Please shut the door.

Would you shut the door, please?

If you’ll shut the door, we’ll be less likely to be interrupted.

Which of these we use depends on how we are related to the person we’re addressing, and on circumstances. We do use different degrees of politeness, and we may sometimes pay careful attention to how to put a request. But on many occasions, we tailor what we say to relationships and circumstances without reflecting on or attending to our choice of phrasing, or even realizing that we are adjusting our words to relationships and circumstances. So, perhaps we are sometimes engaging in a similar, unreflective shading of politeness when we say that we “feel a pain” instead of that we “have a pain”.

Whether or not that is a good explanation, we should not forget result (1): People sometimes use “feel” even for severe pains that they cannot plausibly be taken to regard as unreal.

[Kevin Reuter (2011) “Distinguishing the Appearance from the Reality of Pain” _Journal of Consciousness Studies_ 18(9-10):94-109.]