Some philosophers call it “the hard problem”. Here’s how Norwegian philosopher Hedda Hassel Mørch describes it:
The nature of consciousness seems to be unique among scientific puzzles. Not only do neuroscientists have no fundamental explanation for how it arises from physical states of the brain, we are not even sure whether we ever will….
Our brains do not merely seem to gather and process information. They do not merely undergo biochemical processes. Rather, they create a vivid series of feelings and experiences, such as seeing red, feeling hungry, or being baffled about philosophy. There is something that it’s like to be you, and no one else can ever know that as directly as you do.
Consider the colored objects below. Scientists can describe what happens when a person sees them. They can tell you why the color of a tomato is more like the color of an orange than a lemon. They can point out that if you mix red and yellow light, you’ll get orange. They can use words and numbers to say what’s happening as light is reflected into your eyes and impulses are transmitted along your optic nerves.
But scientists cannot express or capture how any of these colors look when they, or you, or I see them. Words and numbers aren’t up to the task! The best anyone can do is show you examples. See, this is red!
Consider how the word “red” is defined in dictionaries. Merriam-Webster says “red” means “of the color red”. Not terribly helpful. Consider how Wikipedia introduces its article on “Red”:
Red is the color at the longer-wavelengths end of the spectrum of visible light next to orange, at the opposite end from violet. Red color has a predominant light wavelength of roughly 620–740 nanometers.
That would be helpful in some circumstances, but the Wikipedia writers added color pictures of strawberries, a cardinal and the Chinese flag to make things perfectly clear. That’s because pointing out examples is the best way, in one sense the only way, to express the meaning of a word like “red”. That, by the way, is called an “ostensive” definition. When language won’t do the trick, show an example.
The same difficulty applies to the way a violin sounds, the way roses smell and the way tickles tickle. There is something elusive about the way the world appears. There is something incommunicable about experience. Another way of saying this is that the contents of consciousness are a first-person phenomenon. Science as the formal study of the world can describe and explain what’s happening when you hear a violin from a third-person perspective, but the particular sound you hear is beyond words or numbers. There is something about being a person, what it’s like to be a person (or a bat), that has to be experienced firsthand.
Okay, well, that’s interesting. But I’m tempted to say: so what?
That hasn’t been the usual reaction in the history of Western philosophy. Many philosophers have drawn big conclusions from the scientific elusiveness of consciousness. Here, for instance, is Thomas Nagel writing in an exchange of letters a few months ago (he is the author of the famous philosophy paper “What Is It Like to Be a Bat?”):
I do not deny that patterns of neural activation cause experience. What I doubt is that patterns of neural activation alone constitute or are experience—if neural activation is a purely physical process.
The mind-body problem that exercises … me is a problem about what experience is, not how it is caused. 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. Physical concepts describe the world as it is in itself, and not for any conscious subject…. But if subjective experience is not an illusion, the real world includes more than can be described in this way.
I agree … 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.
Nagel accepts that patterns of neural activation cause consciousness, but he doesn’t think they constitute consciousness. I think he has two reasons for saying this. The first is what we’ve been considering so far: consciousness has properties (“raw feels”) that cannot be captured by science. The second is that neural activation is physical – it occurs in space and time – but, according to Nagel, consciousness doesn’t.
His conclusion is that consciousness is a mental phenomenon that somehow stands apart from the rest of the universe. Our experience is supposedly a special kind of “stuff” that’s somehow separate from the physical world of quantum fields, waves and particles. (How events in space and time can make something happen that isn’t in space or time has always been a problem for positions like Nagel’s. Another philosopher, Daniel Dennett, says it would be a miracle.)
My own view is that patterns of neural activation don’t cause consciousness. Nor are they correlated with consciousness. Instead, certain patterns of neural activity are consciousness. In other words, consciousness is having certain kinds of neural activity.
If consciousness is a certain kind of activity in one’s brain, that kind of activity in one’s brain doesn’t cause consciousness. That’s because a phenomenon cannot cause itself, so saying there is a causal relationship between particular kinds of neural activation and consciousness implies that they are separate phenomena. Nor are such patterns of neural activity correlated with consciousness, because, again, saying that two series of events are correlated implies that they are separate phenomena. But having various patterns of neural activity occurring in your brain can be and is consciousness.
This isn’t to deny that there are correlations of a sort. When a scientist or technician measures or records someone’s brain activity (or even their own), they are collecting data from an outside, third-person perspective, i.e. the perspective of the equipment that does the measuring or recording. Looking at the data that’s gathered, we can say there is a correlation between the data and the subject’s consciousness.
But we shouldn’t go on to say that the patterns of neural activity detected in the brain are correlated with the subject’s conscious experience. That would imply that the neural activity stands apart from the conscious experience, when they’re really the same phenomenon talked about in two different ways or considered from two different perspectives (i.e. the third person “outside” perspective and the first-person “inside” point of view).
This view is known as the “identity” theory. To me it seems obvious. Consciousness is brain activity. Certain brain activity is consciousness.
Not so fast, however. How can consciousness and having appropriate brain activity be the same? Don’t “they” have different properties? I don’t think so.
Until there is reason to think otherwise, consciousness should be viewed as a physical process that occurs in the brain. Since the brain is in space and time, so is consciousness. When a person is conscious, they are presented with a phenomenal field, a set of representations, including three-dimensional sights (for most of us) and corresponding sounds (for most of us) and smells, tastes and feelings, as well as thoughts (for most of us). Some of these representations have properties like being red or sweet. These properties belong to the components of the phenomenal field. Another way of saying this is that these properties belong to the experience of having certain brain activity.
Of course, if you were to somehow travel around inside a conscious person’s brain, you wouldn’t see any redness or taste any sweetness. Nor would you find any movie screens or loudspeakers. The most you’d observe would be nerve cells, electrical impulses and chemical reactions with their own distinctive properties. You certainly wouldn’t detect the person’s phenomenal field as the person experiences it.
But if enough of those nerve cells, electrical impulses and chemical reactions are functional, a phenomenal field is present. There is consciousness occurring in there with its various properties, by virtue of the fact that having certain patterns of neural activation is enough for consciousness to occur. (As far as we know, it’s also necessary for consciousness to occur.)
Does this mean that we are only conscious of what’s going on in our brains? In one sense, yes, because that’s where the physical phenomenon of consciousness takes place. In another sense, however, and the most important sense, no, not at all. It’s reasonable to believe that consciousness evolved to help us make our way in the world, partly by representing the world to us. Our conscious experience of the world is damned good, in fact phenomenally good, when you think about it.
In fact, it’s so good that we don’t ordinarily have to think about it at all. We just use it to get around, rather like we use maps, photographs, recordings and other representations. Someone shows you a picture of Miami and asks if you’ve ever been there. Do you say “Yes” or “No” or “What do you mean? Have I ever been in that photograph in your hand?” If you’re not being a smart ass, you’ll answer “Yes” or “No”, because that’s how representations work.
In similar fashion, if someone asks you if you want the banana lying on the table, do you say “Yes” or “No” or “What do you mean? Do I want the portion of my visual field that is mostly yellow with a little bit of brown and green?” Saying “Yes” or “No” is the natural way to respond. It’s true that you can’t keep your consciousness in your glove compartment or put it on Facebook. Plus, your consciousness is what makes it possible to use those other kinds of representations. Consciousness doesn’t represent the world in the same way that maps and photographs do. But in addition to helping us think about the world, remember the past and imagine the future, consciousness also helps us observe and navigate the world, like less simple representations do.
So that’s what I think about consciousness. Understanding how or why consciousness happens in human and animal brains is a major challenge for scientists who study brains, but it isn’t “the hard problem” most philosophers make it out to be.