Metaphysics of Mind, Part 2: The Problem(s) of Consciousness

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Before we begin this episode, I’d like to apologise for the how long it has been since the last episode was released. I went back to work after the UK’s national lockdown ended, enrolled at university to study for a masters degree, took part in Nanowrimo, and am only now getting around to getting this episode done. Needless to say, my studies and my work come before this podcast, but I will try my hardest from now on to get episodes out on time, once a month, as promised in the first episode. I’d also like to take this time to thank those of you who have stuck around and who are still listening despite this absence. Now, Episode 4.

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Hi, and thanks for tuning in to Philosophical Investigations, the podcast all about philosophy with no prior knowledge required. In this episode, we’ll be continuing our look at the metaphysics of mind. However, I’ve shuffled around the schedule so that we can talk about the problem of consciousness today, instead of talking about token physicalism.

You may remember that, in the last episode, we talked about type physicalism and how the theory works: the world is purely physical, and as a result, the brain and the mind are the same thing — there is no such thing as a soul or non-physical mind; what we think of as different types of mental states are identical to corresponding types of brain states — pain is identical to C-fibres firing, for example. We followed this up with two big counterarguments: multiple realizability — that there is, in fact, no necessary link between a brain state type and the corresponding mental state type; and what we called the qualia argument — that qualia, the qualitative aspects of personal experience such as colour, taste, and texture, are not accounted for in this theory.

In this episode, we’ll be continuing this line of investigation and discussing the problem of consciousness, and the various responses to it. I personally believe that qualia are real, and that the problem of consciousness can’t really be solved, but I’ll leave it up to you to decide for yourself if you find the arguments for or against convincing.

So, what is the problem of consciousness, and why does the title have that bracket-s-close-bracket thing going on? Well, that’s because there’s an ongoing debate about how many problems of consciousness there are. Australian philosopher David Chalmers was the first to point out that there is a distinction to be made between the easy and hard problems of consciousness. In his 1995 paper, ‘Facing up to the Problem of Consciousness’, Chalmers writes,

“The easy problems of consciousness are those that seem directly susceptible to the standard methods of cognitive science, whereby a phenomenon is explained in terms of computational or neural mechanisms. The hard problems are those that seem to resist those methods.” (Chalmers, David, “Facing up to the Problem of Consciousness”, in Journal of Consciousness Studies, 2(3):200–19, 1995.)

This creates a distinction based on the method of solution for each of the problems: the easy problems can be solved by investigating the brain scientifically; the hard problems require some other method of investigation. Based on this, the easy problems are relatively straightforward questions, such as how the brain processes images from the eye or sounds from the ear; and how stimuli such as these can result in the changing of brain states and influence action. These problems are solved by rigorous and intense study of the brain and behaviour. The hard problems are more philosophical in nature, with questions such as how conscious experience is formed, where qualia come from, what their nature is, and what function they serve.

The answers to these questions don’t take the same form. For the easy problems, the explanation is merely physical in nature — the same as explaining how a computer is able to process information on a physical level, with circuit boards standing in for neural pathways, and so on; the hard problems require us to take something seemingly immaterial — which is to say, non-physical — and explain it in terms of the physical brain, or to explain how the physical brain can create immaterial experiences.

In a sense, the easy problems of consciousness are solved already, or are due to be solved over time: enough research will show us how the brain processes sound and understands it as language, even if it won’t necessarily tell us how able-bodied people experience hearing. It’s the first-hand experience of what it is like to hear, see, think, and feel that eludes explanation — so far, at least.

But to begin with, we have to ask how we even know that qualia exist. Obviously, we have first-hand experience of qualia, which shows that there is something there; but that first-hand experience doesn’t establish that qualia is separate or distinct from the biomechanical processes that make up the other aspects of life — the non-qualitative aspects. To do this, another Australian philosopher, Frank Jackson, presented an argument in the form of a thought experiment.

Imagine a scientist, Mary, who — for whatever reason — was raised from birth in a black and white room with a black and white TV, from which she gains all her knowledge. She has never seen the sky or the sun, and never seen any other source of colour. Yet, her TV teaches her everything there is to know about the science of colour: she learns about photons, wavelengths, which wavelengths are associated with which colours, how a photon causes a reaction with cones and rods in the eye and produces an electrical signal that is processed by the brain, and so on. She learns everything there is to know about colour — except she never sees it. Jackson writes,

“What will happen when Mary is released from her black and white room or is given a colour television monitor? Will she learn anything or not? It seems just obvious that she will learn something about the world and our visual experience of it. But then it is inescapable that her previous knowledge was incomplete. But she had all the physical information. Ergo there is more [knowledge] to have than that[.]” (Jackson, Frank, “Epiphenomenal Qualia”, The Philosophical Quarterly, Vol. 32, №127. (Apr., 1982), pp. 127–136.)

Jackson’s argument attempts to show that qualia exist separately from the physical properties of the world around us, and that any attempt to explain them away are doomed to fail: “she had all the physical information,” after all. (Jackson, 1982). Nevertheless, there are certainly critics of this argument. Most of these attack the methodological weak points of the thought experiment. For example, one might think that if Mary knows everything there is to know about colour — including how the brain produces the sensation of seeing colours — then she would simply be able to imagine colour. Another counterargument says that Mary might dream in colour, or experience some colour after looking at a bright light and closing her eyes.

These responses, for the most part, can be worked around by editing the argument to avoid them. You might also say that imagining what colour might look like is not that same as knowing what colour looks like and experiencing it first-hand. I have tasted scrambled eggs, rice and peas before; but if I’ve never tasted egg-fried rice, my imagination is at best a guess. Perhaps Mary knows everything there is to know about colour, and how a sensation of colour vision is produced in the brain, but when she tries to imagine seeing blue, she imagines what most people would call red. And this is the point of the argument: even if it’s possible for Mary to imagine seeing colour, she doesn’t know what it is like to see colour. For a point of comparison, see Thomas Nagel’s paper, ‘What is it like to be a bat?’, in which he asks the titular question. The point is that we don’t know, and that we can’t know; we can certainly imagine, but even if we know everything there is to know about bats, we will never know what it is like to be one. Mary has never seen colour; therefore, she does not know what it is like to see it.

Our second argument in favour of qualia as distinct, non-physical aspects of the world comes from many philosophers, but it is, again, championed by David Chalmers. The argument revolves around the idea of philosophical zombies, which are non-conscious, but otherwise unchanged, human beings. They are biomechanically identical with humans (or, in some cases, other animals), and act, speak, and otherwise behave, in exactly the same way we do; the only difference is that they do not experience consciousness.

The argument goes that we can imagine a world, with human beings, buildings, bridges, books, and so on, that is identical to ours in every physical way, but in which no conscious beings exist: every single human and non-human animal is non-conscious, but otherwise unchanged. We can imagine this world that is identical to ours, and yet — it seems — it is completely different. Imagine this world for a second: books, with words printed on their pages, but no ability for anyone to read them; people speaking, arguing about politics, ethics, and religion, but with no ability to comprehend the sounds they’re making — not even knowing that they are making sounds. Essentially, all life is like plant life: reactive to stimuli in a biomechanical sense, but completely noncognizant of what it is, its surroundings, or why it is doing what it is doing.

There is, so the argument goes, something different about this world, even though the physical aspects of it are identical: the philosophical zombies are lacking something, despite lacking nothing on the physicalist view — every part of them is there, because every part of them is physical. If there is a difference between these worlds, then qualia exist, and are essentially non-physical in nature. This argument also has a lot of detractors, and the counterarguments go about trying to defeat the argument by way of showing that you actually can’t imagine such a world, because philosophical zombies are impossible.

Let’s dissect what that means — “philosophical zombies are impossible”. One interpretation is that they are logically impossible. Logical impossibility occurs when there is a contradiction in how something is described that makes it analytically impossible for such a thing to exist. A good example of this is a triangle with four sides: of course, you can’t have a triangle with four sides because a four-sided shape would be a quadrangle, and a triangle must have three sides; such a shape is logically impossible because its own description contradicts itself. Another way of thinking about this is that if you can imagine such a thing, then it is almost certainly logically possible: I can imagine a triangle; I can’t imagine a triangle with four sides. There doesn’t appear to be anything in the description of philosophical zombies that contradicts itself, however, so it appears that philosophical zombies are, at least, logically possible.

The next interpretation is that they are metaphysically impossible, and this is where we find the true meaning of the argument. Philosophical zombies, if we imagine that they exist, would be identical, physically, to conscious humans — yet they have no consciousness. If we are to accept that qualia exist, and that qualia arise in some way from the physical world, or else are related to it, then any being that is precisely identical in every physical way to humans beings must, by necessity, experience qualia. Consider if you would, a toaster that is identical in every physical way to a normal toaster, except when you put the bread in, the toaster doesn’t toast it; of course, if it is identical in every physical way, it will make toast. Similarly, a human, provided they are physically composed in the right way to allow it (i.e., excluding people in persistent vegetative states, etc.), cannot be without consciousness — it is a necessary result of the physical composition of their brain.

It seems, I think, that the detractors are correct on this one: philosophical zombies are metaphysically impossible. But the question arises, does that make a difference? Suppose we can imagine philosophical zombies despite their metaphysical impossibility — that seems certainly true. Then doesn’t the argument stand? The argument isn’t about what is or isn’t possible, but what one can imagine: we can imagine a world without consciousness that is physically identical to ours, and so it seems that — even if such a world can’t actually exist — there is evidence that qualia are essentially non-physical. As a result, it doesn’t seem particularly relevant whether or not philosophical zombies are possible; the only relevant fact is that they can demonstrate, in conception at least, a distinction between qualia and the physical world.

There we have the two most common and popular arguments for qualia as non-physical in nature. This produces what is known as ‘the explanatory gap’, wherein the physicalist cannot explain the link between qualia and the physical world. Bridging this gap has been attempted many times, but never to much success. If it can’t be done, then physicalism is presumed to be false: there exist some non-physical properties of the world, therefore not everything in the world is physical.

There are, of course, people who reject this conclusion to the explanatory gap. First, you have the die-hard faithful who believe scientific research will solve the issue, given enough time. After all, scientific research has solved many other problems initially posed by philosophy; there’s no reason to say the researchers in their lab coats won’t do it again. But this argument is rather weak: there’s no reason to suppose scientific research won’t bridge the gap — sure — but there’s no reason to suppose that it ever will. It essentially just kicks the can down the road for future physicalists to worry about, which is never a good sign.

Related, though distinct, is Daniel Dennett’s argument that the distinction we made at the beginning, between the easy and hard problems, is, in fact, mistaken. Dennett argues that once all the easy problems are solved — which most philosophers are confident can happen through continued scientific research — the hard problems will disappear. In other words, consciousness and qualia exist in the functions of the brain, and it is a sort of trick of the mind that it appears non-physical to us. This is a highly contentious argument — especially as Dennett’s ultimate conclusion is that qualia don’t exist and are merely a product of ‘folk psychology’. It seems dubious to claim that qualia consist in the various functions of the brain, since there is no explanation that goes along with it to say how such a thing represents itself as non-physical, so to speak. He solves one problem by creating another: why and how does the brain trick us into thinking qualia are non-physical? Until such a question is answered, Dennett’s response to the hard problem stays in limbo — an incomplete argument.

The last thing we’ll talk about are the responses to the explanatory gap that accept that the gap is irresolvable. Whereas physicalism attempts to reduce qualia to physical terms, these theories are grouped together as non-reductionism.

The first to discuss is epiphenomenalism, which is also sometimes called property dualism. Under this view, the only substance in the world is physical in nature, but physical substance can have either physical or mental properties. These mental properties are what we call qualia or consciousness, and while they are produced by the brain, they do not cause anything else to happen: the mechanisms of the brain interpret stimuli, cause bodily movement and so on, and qualia are merely a biproduct of that process. Because they are unable to be a cause to anything else, we call them ‘causally inert’. The obvious issue with this is that, while it accepts that qualia exist, it doesn’t explain how the brain produces qualia — that question is presumably left to scientists to answer. It also stipulates the existence of something — mental properties of physical beings — which have no effect on the world because they are, according to the theory, causally inert; this makes them unverifiable, and so there is no way to scientifically test the theory — despite being a physicalist theory. Finally, the mental properties being causally inert makes them ‘nomological danglers’ — there in name only, dangling with nothing to do. This criticism, levied against epiphenomenalism by Jack Smart, highlights that the mental properties were theorised just to get around this criticism, and have no larger role to play because of the nature of their theoretical origins. As a result, epiphenomenalism — while popular among philosophers for a time — has fallen out of favour as an unsatisfactory answer to the hard problem.

The second theory is panpsychism, which is generally taken to say that all physical objects in the world have some kind of consciousness. There are many kinds of panpsychism, both philosophical and religious, but our focus here is on what Galen Strawson calls ‘realistic physicalism’. Traditionally, physicalism has assumed that the physical substance is non-experiential, and as a result, qualia must be explained away or somehow reduced to purely non-experiential, physical terms. But what if the physical world was conscious already? Perhaps a rock isn’t able to reason about ethics and government, but there is a piece of consciousness there — very basic and undeveloped. According to this theory, every atom in the universe has a small piece of undeveloped consciousness contained within, and once enough are collected together in the right pattern, they are able to team up to produce fully-fledged consciousness, with qualia and reasoning. This process is called emergence because fully-fledged consciousness emerges from things that, on their own, are not fully conscious to begin with. The mistake, Strawson says, that physicalists of the past have made is assuming that the physical world is distinct from the mental, and that the mental doesn’t exist. Instead, on this view, they are the same thing: every physical thing is mental in a small way, until enough come together in the right way, and consciousness emerges.

There is an obvious problem with this theory: it’s wacky as all hell. But the reason it’s wacky is because it’s new, relatively speaking: it isn’t familiar to us, and so it appears quite strange. The bigger problem is that there’s just no evidence of it, besides our own consciousness, and if we argue that the theory is true because humans are conscious beings, then we have created a circular argument — one that justifies itself — which isn’t a good kind of argument. Ultimately, I don’t think the theory works for the simple reason that there’s no reason to believe it.

Finally, the last theory is known as substance dualism, which is the belief that there exists a non-physical, entirely mental substance in addition to the physical substance of physicalism. This mental substance is known as the mind or the soul, and people have believed in its existence since as far back as the oldest surviving religious and philosophical texts. It has a very long and storied background, with many different interpretations, and for that reason, we’ll have to look at it in the next episode.

In this episode, we’ve talked all about qualia, the easy and hard problems of consciousness, and the arguments in favour of qualia as distinct, non-physical elements of experience; we also looked at some responses to the problems of consciousness and some alternative theories that try to get around it. As always, you can find the transcript, sources and notes for this and all episodes at the link in the episode description, or you can take yourself to <medium.com/philosophical-investigations>. Apologies again for the lateness of the episode.

Thanks for listening.

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Bibliography

[1] Chalmers, David, “Facing up to the Problem of Consciousness”, in Journal of Consciousness Studies, 2(3):200–19, 1995.

[2] Jackson, Frank, “Epiphenomenal Qualia”, The Philosophical Quarterly, Vol. 32, №127. (Apr., 1982), pp. 127–136.

[3] Robert J. Howell and Torin Alter, “Hard Problem of Consciousness” (2009), Scholarpedia, 4(6):4948. URL = <http://www.scholarpedia.org/article/Hard_problem_of_consciousness> [Accessed 2020–12–10]

[4] Van Gulick, Robert, “Consciousness”, The Stanford Encyclopedia of Philosophy (Spring 2018 Edition), Edward N. Zalta (ed.), URL = <https://plato.stanford.edu/archives/spr2018/entries/consciousness/>.

[5] Kirk, Robert, “Zombies”, The Stanford Encyclopedia of Philosophy (Spring 2019 Edition), Edward N. Zalta (ed.), URL = <https://plato.stanford.edu/archives/spr2019/entries/zombies/>.

[6] Weisberg, Joshua, “Hard Problem of Consciousness”, Internet Encyclopedia of Philosophy. URL = <https://iep.utm.edu/hard-con/> [Accessed 2020–12–10]

[7] Kind, Amy, “Qualia”, Internet Encyclopedia of Philosophy. URL = <https://iep.utm.edu/qualia/> [Accessed 2020–12–10]