Touching a Nerve: Our Brains, Our Selves by Patricia S. Churchland

Patricia Churchland is a well-known professor of philosophy. She is married to another well-known professor of philosophy, Paul Churchland. The Churchlands were profiled in The New Yorker in 2014 in an article called “Two Heads: A Marriage Devoted to the Mind-Body Problem”. They are both associated with a philosophical view known as “eliminative materialism”. Very briefly, it’s the idea that we are mammals, but with especially complex mammalian brains. and that understanding the brain is all we need in order to understand the mind. In fact, once we understand the brain sufficiently well, we (or scientists anyway) will be able to stop using (eliminate) common mental terms like “belief” and “desire” and “intention”, since those terms won’t correspond very well to what actually goes on in the brain.

So when I began reading Touching a Nerve, I expected to learn more about their distinctive philosophical position. Instead, Prof. Churchland describes the latest results in neuroscience and explains what scientists believe goes on in the brain when we live our daily lives, i.e. when we walk around, look at things, think about things, go to sleep, dream or suffer from illnesses like epilepsy and somnambulism. She admits that we still don’t understand a lot about the brain, but points out that neuroscience is a relatively new discipline and that it’s made a great deal of progress. I especially enjoyed her discussion of what happens in the brain that apparently allows us to be conscious in general (not asleep and not in a coma) vs. what happens when we are conscious of something in particular (like a particular sound), and her reflections on reductionism and scientism, two terms often used as pejoratives but that sound very sensible coming from her.

The closest she comes to mentioning eliminative materialism is in the following passage, when she seems to agree (contrary to my expectations given what I knew about the Churchlands) that common mental terms won’t ever wither away:

If, as seems increasingly likely, dreaming, learning, remembering, and being consciously aware are activities of the physical brain, it does not follow that they are not real. Rather, the point is that their reality depends on a neural reality… Nervous systems have many levels of organization, from molecules to the whole brain, and research on all levels contributes to our wider and deeper understanding [263].

I should also mention that the professor shares a number of stories from her childhood, growing up on a farm in Canada, that relate to the subject of the book. She also has an enjoyable style, mixing in expressions you might not expect in a book like this. For example, she says that reporting scientific discoveries “in a way that is both accurate and understandable” in the news media “takes a highly knowledgeable journalist who has the writing talent to put the hay down where the goats can get it” [256].

Here is how the book ends [266]:

Bertrand Russell, philosopher and mathematician, has the last word:

“Even if the open windows of science at first make us shiver after the cozy indoor warmth of traditional humanizing myths, in the end the fresh air brings vigor, and the great spaces have a splendor of their own.”

Rock on, Bertie.

Consciousness As Mental, As Physical

It’s been argued that a scientist who grew up in a black and white room and never saw the color red could learn everything there is to know about the physics of light and the physiology of the human body, including what happens in the brain when someone sees red, but not know what red looks like. Presumably, a blind scientist with the same training would be in the very same position. Likewise, a deaf scientist could know everything about the physics and physiology involved in hearing a violin but not really know what a violin sounds like. This is supposed to show that there is something in the universe beyond the reach of the physical sciences: the mysterious mental phenomenon of consciousness.

“Mental” is a word I haven’t used much (or at all) in writing about consciousness, yet consciousness is clearly a mental phenomenon if anything is. But what does it mean for a phenomenon to be “mental”?

The obvious answer, although it’s not very helpful, is that “mental” means “not physical”. But what does that mean?

An exchange of letters I referred to last month between the philosopher Thomas Nagel and a professor of bioengineering, Roy Black, tries to deal with the question. Prof. Black criticizes the idea that “nonphysical factors” are involved in consciousness:

As is frequently noted, the physical basis of life itself used to be just as mysterious as consciousness, and it’s now well explained by biochemistry and molecular biology, without nonphysical factors. So although science as we know it doesn’t explain the link between neurons and consciousness, why expect the link to be “nonphysical” rather than “novel physical”? What is a nonphysical factor, anyway? If the dark energy propelling the expansion of the universe, the strong force holding atomic nuclei together, etc., etc., are physical, do we really need anything more exotic?

… Lots of things in biology—like the development of an organism from an egg—seem impossible, until we stretch our imagination to conceive of simple precursors and mechanisms that could have been worked on by natural selection over billions of years. To quote one of [the philosopher Daniel Dennett’s] nice lines, “evolution is a process that depends on amplifying things that almost never happen.” We need to determine what “thing,” what activity of neurons beyond activating other neurons, was amplified to the point that consciousness arose. What would a precursor of “feeling like” be? That’s what we need to stretch our imaginations further to figure out.

Prof. Nagel responds, but his response is based on an assumption:

The difficulty is that conscious experience has an essentially subjective character—what it is like for its subject, from the inside—that purely physical processes do not share [how does he know this?]. Physical concepts describe the world as it is in itself, and not for any conscious subject….

I agree with Black that “we need to determine what ‘thing’, what activity of neurons beyond activating other neurons, was amplified to the point that consciousness arose.” But I believe this will require that we attribute to neurons, and perhaps to still more basic physical things and processes, some properties that in the right combination are capable of constituting subjects of experience like ourselves, to whom sunsets and chocolate and violins look and taste and sound as they do. These, if they are ever discovered, will not be physical properties, because physical properties, however sophisticated and complex, characterize only the order of the world extended in space and time, not how things appear from any particular point of view [again, how does he know this?].

Nagel’s assumption is that a purely physical process cannot have a subjective character (it cannot “feel like something”). It cannot be “how things appear” from a particular point of view. But if consciousness is a physical process, it does have a subjective character. In that case, how things feel or appear are indeed physical properties of a process that occurs in space and time (it happens inside your head when you’re conscious).

Here’s my take on the mental/physical distinction. Nobody knows what the universe contains at the most fundamental level (or if there is a most fundamental level). But suppose that quantum field theory is correct and, quoting Prof. David Tong of Cambridge University (who I wrote about earlier this year):

The best theories we have tell us that the fundamental building blocks of nature are not particles but something much more nebulous and abstract. The fundamental building blocks of nature are fluid-like substances which are spread throughout the entire universe and ripple in strange and interesting ways. That’s the fundamental reality in which we live. These fluid-like substances, we have a name for, we call them “fields”.

Furthermore, when the fields ripple or are agitated in certain ways, we get sub-atomic particles. An electron, for example, is a kind of ripple in the electron field.

So when I say that consciousness is a physical process, what I’m saying is that consciousness is at bottom constructed from one or more quantum-level fields – or whatever the fundamental building blocks of the universe are – that somehow interact with the quantum-level fields – or other building blocks – from which everything else in the universe is constructed. Maybe consciousness involves a kind of fundamental field that physicists can’t measure or detect yet. Maybe it involves a new kind of interaction between fundamental fields that physicists already know about.

But consciousness seems to be part of the natural world in the same way other physical phenomena are. And because it’s part of the natural world – not a kind of free-floating spiritual or supernatural substance or phenomenon – consciousness can represent other physical events and processes outside itself. Consciousness being part of the world is why we can be consciously aware of our bodies and the world around us.

“Mental”, therefore, refers to what happens in our minds, but at bottom mental phenomena are physical phenomena. Consciousness, like gravity, digestion and baseball, is one of the things that happens in the world. In other words, the “mental” is a subset of the “physical”. Or so it seems to me.

The Way Consciousness Is

Thinking about the United States plumbing the depths of kakistocracy (rule by the worst) is all well and good, but back to consciousness.

The human brain is the most complex object anyone has ever tried to understand. It might be the most complex object in the universe. We might never understand how it works. Robert Burton, a neurologist, writes about being surprised by a patient with a paranoid fear of the FBI that was apparently caused by a mutation in his brain:

Though I didn’t know it at the time, I had run headlong into the “hard problem of consciousness,” the enigma of how physical brain mechanisms create purely subjective mental states. In the subsequent 50 years, what was once fodder for neurologists’ late night speculations has mushroomed into the preeminent question in the philosophy of mind. As an intellectual challenge, there is no equal to wondering how subatomic particles, mindless cells, synapses, and neurotransmitters create the experience of red, the beauty of a sunset, the euphoria of lust, the transcendence of music, or in this case, intractable paranoia.

Neuroscientists have long known which general areas of the brain and their connections are necessary for the state of consciousness. By observing both the effects of localized and generalized brain insults such as anoxia [total lack of oxygen] and anesthesia, none of us seriously doubt that consciousness arises from discrete brain mechanisms. Because these mechanisms are consistent with general biological principles, it’s likely that, with further technical advances, we will uncover how the brain generates consciousness.

However, such knowledge doesn’t translate into an explanation for the what of consciousness—that state of awareness of one’s surroundings and self, the experience of one’s feelings and thoughts. Imagine a hypothetical where you could mix nine parts oxytocin, 17 parts serotonin, and 11 parts dopamine into a solution that would make 100 percent of people feel a sense of infatuation 100 percent of the time. Knowing the precise chemical trigger for the sensation of infatuation (the how) tells you little about the nature of the resulting feeling (the what).

But why should we expect that knowing what chemicals cause the feeling of infatuation would tell us anything about what infatuation feels like? Aren’t those two different questions?

Suppose, however, that we keep improving our techniques for studying the brain, as Burton suggests, and eventually figure out how certain kinds of brain activity become consciousness. It doesn’t seem impossible that one day (maybe 1,000 years in the future) that we will fully understand how “subatomic particles, mindless cells, synapses, and neurotransmitters” allow us to be conscious, just as well as we understand how lungs allow us to breathe (although lungs are a lot less complicated than brains). Suppose we discover how one kind of brain activity becomes a feeling of infatuation and another kind becomes a feeling of resentment. 

Burton implies that we would still be left with what he calls the “what” question, although it might be better to call it the “why” question. Why does our consciousness have the specific properties it does? Why does a note on a violin sound just the way it does? Why does red look like this and not like this or this? In the case of color, scientists might understand perfectly well the relationship between different wavelengths of light, the physiology of our eyes and nervous system, and the colors we see. They would understand that such and such conditions, structures and processes are correlated with seeing red and others are correlated with seeing blue. All of our “how does this happen?” questions would have been answered. So would it still make sense to ask why a particular kind of light looks the way it does or a particular feeling feels the way it does?

I’m not sure it would. Once we understood what leads to colors looking the way they do, or what makes feelings feel the way they do, any “why” questions might disappear. Once we understand the “how” of consciousness, maybe there won’t be anything more to figure out. If there are any neurologists or philosophers still asking “why”, the best answer will be “that’s just the way it is” or “stop asking questions and go to sleep”.

That wouldn’t necessarily be a bad thing. After all, in science, we sometimes arrive at what appear to be “brute” facts. Why is the speed of light in a vacuum 186,282 miles per second instead of 186,300 miles per second? We may never know. That’s just the way the universe works. No further explanation is available. If you have a problem with our speed of light, go live in another universe. If you don’t like the particular colors you see, keep your eyes closed. Or become a cat.

Next up on this subject, assuming I stay conscious: What does it mean to say consciousness is a physical phenomenon? It’s obviously a mental phenomenon, so how can it be a physical one too?

What We Have In Mind (Consciousness Again)

Last week, I suggested that consciousness is a type of brain activity, the kind that consists in having a phenomenal field that includes sights, sounds, pains and the internal monologue depicted by authors as the “stream of consciousness”.

I also recommended that we reserve the phrase “conscious of” for the most important things we’re conscious of, things like our everyday surroundings, our feelings and our thoughts, not consciousness itself. This approach would rule out questions like “Are you conscious of consciousness?” that to me seem misguided and misleading. I don’t think we’re conscious of consciousness, but rather conscious of other things.

To say that we’re conscious “of” other things is to say that the components of consciousness represent other things. Thus, some of the brain activity that is consciousness represents things outside our bodies (e.g. trees falling in the forest). Some of it represents things inside our bodies (e.g. heartburn). And some represents things that exist neither inside nor outside our bodies: abstract things like possibilities (e.g. sanity in Washington), fictional characters (Wonder Woman) and ideas (justice or the number twelve).

From an article about dreaming, which is usually considered a kind of consciousness:

One of the main functions of our brain is to constantly create a model of the world around us, a sort of virtual reality that helps us interact with our environment.

When we’re awake, that model is heavily influenced by what we are seeing and hearing and feeling. But during sleep, when there’s not much input from our senses, the brain’s model of the world is more likely to rely on internal information, like memories or expectations.

I’d add that the model is also a model of the world within us and the abstract world of memory, intention and imagination. But thinking of the model our brains create as “a sort of virtual reality” is what I have in mind (that’s a pun). It’s the “sort” of virtual reality that isn’t virtual, however. Patterns of neural activation in the brain (what the model is made of) are quite real. And it’s a model or representation of other things that are quite real too, like falling trees and sprained ankles.

One of the things that makes our conscious model interesting is that it includes events and processes that are strictly or primarily mental, like having a premonition. I don’t know if such things are representations of unconscious mental events and processes. Maybe they aren’t representations at all; maybe they’re patterns of neural activation that don’t refer to or represent anything else. But the evidence suggests that we all have a lot of unconscious brain activity that plays a very large role in what we think and how we feel.

So it would be consistent with the view I’m trying to explain that when you have something like a premonition, what you’re conscious of is a representation of the underlying brain activity (the unconscious premonition processing), as well as any related events in your body (like chills).

To sum up, the position I’ve arrived at seems to be a strange, possibly ridiculous mixture of ideas associated with two great philosophers who are generally seen as opponents: the idealist George Berkeley and the materialist Thomas Hobbes.

Berkeley (1685-1753) argued that nothing exists independently of minds: “To be is to be perceived (or to perceive)”. A person is an immaterial mind or soul. The physical world (the Earth, for example) doesn’t exist independently of our minds. Fortunately, our individual minds are able to get along because God (a kind of super-mind) synchronizes our perceptions. He makes sure that when I perceive a red apple (in my mind), you do too.

Hobbes (1588-1679) argued that nothing exists except physical stuff. We human beings, including our minds, are material things. Even God may be a kind of material being. When I see a red apple, and you see a red apple, therefore, it’s because there’s an apple out there and it’s red. That’s the whole story. 

Where I’ve ended up is to agree with Berkeley that our consciousness has the various elements in it that he called “perceptions” and “ideas”. But I agree with Hobbes that consciousness is a physical phenomenon, a very cool physical phenomenon, but a physical one just the same. And the reason my perceptions usually line up with yours so nicely is because our perceptions represent the same physical world, albeit observed from our individual perspectives. 

Being Conscious, But Not of Consciousness

A reader (!) asks: Does [what you posted about consciousness yesterday three days ago] mean that we are only conscious of what’s going on in our brains?

That’s an excellent question. When I say that consciousness is certain kinds of brain activity or patterns of neural activation, it may sound like I’m saying that we’re only conscious of brain activity. In other words, we’re not conscious of the rest of the world or the rest of our bodies.

Given what I’m saying about consciousness, I might explain that we are “directly” conscious of our brain activity and “indirectly” conscious of the rest of the world. Or I could say that our consciousness of what’s going on in our heads is “immediate”, while our awareness of everything else is “mediated”, i.e. conveyed through intermediaries, such as the air that carries sound waves to our ears and the nerve impulses that travel from all over our body to our brain.

So when I raised this question yesterday (“Does this mean we are only conscious of what’s going on in our brains?”), I began by saying “in one sense, yes, because that’s where the physical phenomenon of consciousness takes place”. I then said, however, that in the most important sense our brain activity enables us to be aware of what’s happening outside our brains.

Actually, I recommend that we reserve phrases like “conscious of”, “aware of” or “what we experience” for the things we are ordinarily and importantly conscious of. That’s the standard way of speaking and the best way to describe what’s happening when we are conscious. For instance, when you’re awake, are you conscious of your surroundings? When you raise your arm, do you experience any discomfort? Now that you’re on Social Security, are you experiencing any memory loss?

Asking whether we are conscious of what’s going on in our brains amounts to asking whether we are conscious of our consciousness. It’s a misleading question. It’s like asking someone at the North Pole which way is north. To be conscious is to have a certain kind of brain activity. To be conscious of whatever is to be conscious of something other than your brain activity. That’s because there is no way to be conscious of your consciousness. There is no mechanism, no mental apparatus, no meta-consciousness that allows being conscious of consciousness. Consciousness just is. The world you see, that rumbling in your stomach, is what it looks like, feels like, to have the right kind of brain activity. 

You can think about being conscious. We’re doing that right now. But that’s different from being conscious of consciousness. When you think about consciousness, you’re conscious of your thoughts (about consciousness), just like you can be conscious of thoughts about other things. But consciousness itself just is (I could say it is what it is, but that would be redundant and annoying).

Could an evil demon be tricking you, like Descartes wondered? Could you be a brain in a vat, like later philosophers ask themselves? Sure, it’s possible to be seriously wrong about what you’re conscious of. Maybe what you’re conscious of isn’t ever what you think it is. I’m not worried. You shouldn’t be either. 

If a tree falls in the forest, does it make a sound? Yes, it makes the air vibrate and if it creates enough vibrations and there’s anyone around who’s conscious and isn’t deaf, they’ll hear (be conscious of) the crashing sound. 

I’m not sure what I’ve been saying makes sense. I’ve thought about this topic for a long time but never expressed my thoughts this way before. Maybe what I’m saying is way off the track, but it’s all I’ve got right now. Maybe I’ll get back to it again. In the meantime, stay conscious.

In my opinion, that implies being conscious of other things, not consciousness.