The problem of consciousness hangs over both science and philosophy like a bad smell. Nobody is sure what to do with it. The problem of consciousness makes everything uncertain and unclear. In this article, Riccardo Manzotti offers us an ingeniously simple solution to this problem. So simple it becomes almost unintuitive. But possibly, this is exactly what we have needed to finally get to grips with consciousness.
Einstein claimed that when “the consistent use of traditional fundamental concepts leads us to paradoxes difficult to resolve […] it is necessary over and over again to engage in a critique of fundamental concepts, in order that we may not unconsciously be ruled by them”. The problem of consciousness falls precisely in this category. From the pioneering studies of Hermann von Helmholtz, more than 150 years ago, to the recent works of Anil Seth, Giulio Tononi, Christof Koch, neuroscientists have been trying to find something that resembles consciousness inside the nervous system; so far they have always failed to address the key issue: how can a brain experience something that the brain is not. The neural evidence they have observed never amounts to more than correlations. The nervous system is home to all kinds of interesting phenomena, but no consciousness has been found. In fact, the more we know about what goes on in the brain, the less space remains to find anything unexpected.
To cope with this discouraging situation, existing theories of consciousness have put forward various ad hoc hypotheses (IIT, quantum-based theories, emergent properties, panpsychism, illusionism) that simply shift the mystery elsewhere. In the spirit of Einstein’s remark, it is time to take a step back in order to move forward. This is precisely what the mind-object identity hypothesis (MOI) sets out to do. It is a radically physicalist hypothesis that proposes to locate consciousness without adding to or changing our scientific view of reality. If anything, it requires us to set aside the remnants of naïve naturalism that still haunt so much of consciousness research and start taking seriously what physics tells us.
Ever since Plato and more forcefully Descartes, we have conceived the matter thus: I am in here and the world is out there because I am separate from the world
Let’s start with the basics. At this precise moment, there is something in the physical world which is identical with you. As to what that something is in your case, I can only make educated guesses. However, I can reasonably assume that, if we start with perception, there will be a world of things that very likely includes a laptop, a room, a window, a desk, maybe a purple mug containing hot coffee. This is a physical subset of the physical world. So far, so good. No mystery yet. However, ever since Plato and more forcefully Descartes, we have conceived the matter thus: I am in here and the world is out there because I am separate from the world. This way of conceiving the matter produces a mystery. How can the world be present here as a part of me, while continuing to be out there? All solutions have invariably suggested that the subject must have some form of superpower, called consciousness (or aboutness, or representations, or mental images) which is the capacity, that is, to present the world inside the self (be it a body, a mind, or a soul) leaving the world outside.
As soon as we posit this pseudo-solution to what I will show is a pseudo-problem, consciousness becomes an unsolvable conundrum.
Can we do better? Yes, but only if we challenge our main premise that we are separate from the world. This is what MOI does. The hypothesis is simple: there is a world of physical objects that take place relative to your body – the laptop, the mug, and all the rest. There is no inside and no outside. There is no here and no there. There is just your existence, you, as one would expect in a physical world. Your ‘conscious experience’ of the laptop and the mug is nothing other than the laptop and the mug as they take place relative to your body. So what is your experience? It is the subset of physical objects taking place relative to your body. The mind is identical with the (relative) object. Hence the name of Mind-Object Identity.
The advantages of MOI are several. First, it is a physicalist hypothesis that is entirely compatible with all the science we have. Second, it does not require any ad hoc hypothesis (Ockham would approve). Third, it is compatible with our experience of the world (or perhaps I should write with “our existence as the world”)? Fourth, it explains many phenomena that puzzle the neuroscientists, such as the stability of perception despite the extreme variability of neural processes.
But hang on! I can hear many readers protesting that this hypothesis flies in the face of physicalism. How can you place our existence outside the body? But actually, physicalism has never been body-ism or brain-ism. Physicalism merely states that whatever we are must be part of the physical world. It does not say which part. MOI concurs that you and I are entirely physical; what we call consciousness is outside the head, yes, but part of the physical world.
Is MOI an idealist/panpsychist view? No. MOI is the ultimate physicalist view; it has no place for anything but objects in relation to each other (relative objects). Panpsychism supposes a mental patina spread over everything: it is just dualism on steroids. In MOI there is just one world made up of objects whose existence is defined by their relation with other objects (the mug in your world is as the mug takes place relative to your body and not the ideal or absolute mug). So no panpsychism.
Idealism, on the other hand, requires thinkers who have ideas, while MOI, has no place either for ideas or thinkers, only for relative objects that bring each other into existence by means of mutual causal relations. We are objects, yet not the objects – our bodies – that scientists have always pointed to, anxious that not to identify self with body meant accepting the notion of an immaterial soul. Fortunately, MOI advances another solution: we are the objects that take place relative to our bodies.
Once the identity between ourselves and the subset of objects relative to our body is accepted, there is no need to look for any “special thing inside the brain”
Two objections immediately have to be met: the variability of experience and experience’s supposed separation from the real world, particularly in dreams, imagination, memory, and hallucinations. Let’s tackle variability first. It’s true that different people perceive reality differently, at least to some degree? Take the purple mug on your desk. Due to color blindness, I might perceive it as reddish, while for you it’s more bluish. Doesn’t this prove that I see a mental mug, different from your mental mug? Nope. As a matter of fact, physics already provides a simple explanation: many physical properties are relative. The properties we perceive are all relative properties, relative, that is, to our specific body.
Let me give a very standard example from physics: relative velocity. On the highway, you’re driving at 30 mph. I’m driving at 50 mph. Ann is driving at 40 mph. John, who is very fast, is driving at 60 mph. All these speeds are relative to the ground of course, the tarmac. Yet, John is driving at 30 mph relative to you, 10 mph relative to me, and 20 mph relative to Ann. What is John’s real velocity then? The question is meaningless. All velocities are both real and relative. John’s car has as many relative velocities as there are objects around it. This is standard physics. The same rationale can be applied to all properties: length, size, shape, colors, smell, taste, heat, weight, texture, pitch. With MOI, the properties we find in our existence are only those taking place relative to our body.
Consider color. Your cell phone is displaying a white background. But if you get closer, or use a lens, you’ll see a uniformly-spaced grid of red, green and blue dots. So, is it really white, or really a multicolored mosaic? Both. Given the properties of your body, to which it is relative, the screen is white at a distance and colored close up. Given another body, something else.
The notion of subjectivity is an invention, a historical response to the desire to sustain our belief in a physical world made of either abstract Platonic forms or naïve absolute physical objects perceived by means of invisible mental properties. But if we consider the physical world in terms of relative properties we will have more than enough to explain why we live in different yet intertwined physical worlds.
Does this put you and, say, a camera on the same level? No. Because my body and the camera are two very different objects and hence bring very different relative properties into existence.
I have so far addressed the first objection: the variability of existence. What about the apparent autonomy of consciousness as in dreams, imagination and hallucinations? Are they not evidence that our consciousness is indeed distinct from the physical world? While I have no hope of providing a complete explanation, I will nevertheless give a general idea of the solution by starting with perception and then showing that dreams, imagination and hallucinations are a special case of it.
In our daily lives, the naïve model is that we are here and now. We imagine our existence as a point in space and time. However, this is contrary to our experience and to physics. We live in a spread now – consisting of melodies, voices, distant objects, gestures – that extends over a finite interval of time. How long is this interval that encompasses our existence? For practical purposes, we usually assume that it is very short. But such an assumption is not conditioned by a physical threshold. It is only a general assumption. Measured in terms of the time it takes light to reach our bodies, the sun is 8 minutes away from our bodies. Bright Jupiter can be up to an hour away. Stars can be years in the past. The traditional explanation is that we do not see the constellations themselves, but their images carried by light. Yet, if this model were correct, we would not see the world at all but images carried by light. We would then need to explain what the nature of those images is and how they are ‘represented’ to us, and we would be back to square one. These cases suggest that perception is not only spatially extended but also temporally extended. This is the first element we need.
The nervous system is home to all kinds of interesting phenomena, but no consciousness has been found
Once physical processes are considered to be spatially and temporally extended, memory, dreams, imagination and hallucinations can be explained as cases of perception in which the object of perception is a gerrymandered collection of objects and events that have taken place and are still affecting the present. So you dream of the proverbial pink elephant because, as in a kaleidoscope, two separate events (a pink something and an elephant) have merged into one through causal processes. Instead of explaining the perception as a reliable hallucination, MOI explains hallucinations as delayed perceptions. In such cases, MOI suggests that we are simply identical with such an object distributed in space and time. Is this any different from perception? Not at all, in perception too we are identical with an object distributed in space and time, only it is usually closer to our body.
If you dream of your deceased relatives with whom you enjoyed playing as a child, they are of course no longer there. But their causal influence is still there. Is not it the same with perception? MOI asks you to look at the physical world anew in the form of spatio-temporally extended processes.
In fact, there is very strong and consistent empirical evidence in favor of this model of dreams and hallucinations, namely that to the best of our knowledge our oneiric experiences are so mundane. We never experience radically alien basic properties. Our dreams or hallucinations are populated by our everyday, familiar properties – colors, shapes, bodies, tastes, sounds, voices – albeit jumbled and recombined in surprisingly unexpected ways.
Imagination is also a valid example of such identity with the physical world. For example, you can easily imagine a pink elephant with wings, but you cannot imagine a color you have not seen or a taste you have not perceived. Nevertheless, we should not despair. Recombination is extremely powerful as evolution shows – all living things are nothing more than the recombination of four bases.
This also provides an explanation for why we hallucinate or dream. We do this because, either due to physiological/environmental conditions (sleep) or unusual circumstances (drugs/illnesses/disorders), the relevance of the near world is diminished and the influx of past events takes over in any order.
What about the many problems that consciousness studies is so replete with – intentionality, aboutness, first-person perspective, reflexivity, self-consciousness? How does MOI deal with them? While I cannot address them individually here, I can hint at a general strategy. They are all pseudo-problems created to deal with the false premise I aimed at at the beginning, namely the separation between subject and object. They play the same role as the epicycles played to hold geocentrism. Once the false premise is put aside, they will follow.
To recap, different people perceive objects differently because they have different bodies. Thus they are identical with different relative worlds. There are as many relative worlds as bodies. The role of your body is that of providing a causal reference frame to the world that you are identical with. The expression “I perceive the world from my relative position” becomes “there is a world of physical properties relative to the position of my body – that world is what I call I”.
MOI does neither claim that, say, a camera or a microphone have experience of the world, nor that experience is everywhere. MOI suggests that the so-called hard problem has always been a pseudo-problem resulting from the assumption that subject and object are separate, and consequently the search for a ghost world inside the body and specifically the brain. Once the identity between ourselves and the subset of objects relative to our body is accepted, there is no need to look for any “special thing inside the brain”. The existence of that special thing (call it qualia, consciousness, or phenomenal experience) was the byproduct of a naïve conception of the physical world in terms of absolute objects combined with the common belief that we are distinct from the physical world. In fact, the world is not divided into ordinary objects and mental objects. There are only (relative) objects. So which objects are you exactly? You are made of those objects that exist relative to your body, which is just yet another object. Once we set the distinction between us and the world, the objects (the desk, the mug) that exist relative to our body are all we want. We no longer need to place us inside our head. Look at your existence and you’ll find out. You are the objects you find in your existence. Perception is identity. What you perceive is what you are. Has consciousness really been hidden in plain sight all this time?
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