Mind and Body

Rene Descartes 1596-1650

Descartes took it for granted that "mind" or "soul" existed in different universes. He wondered about how these universes communicated. Specifically, he wondered how "spirit" can move "matter".

There are many who still take the idea of the spirit world seriously. They imagine the "soul" can be separated from the body and migrates on to some other universe (heaven) at death or somehow migrate to another body. Let's put this belief system to one side. From here on, I will speak to those who don't take this idea seriously.

These days, those of us who are scientifically inclined imagine the "mind" to be a phenomenon that somehow happens in the Universe that is governed by physical law (and perhaps other laws so far undiscovered). Exactly how this happens is a live debate and a key area of investigation in the new university departments of "Cognitive Studies". These same departments work on another hot subject: machine learning and "artificial intelligence". Naturally, these two issues tend to overlap, producing "computational" theories of "mind". It's quite respectable these days to consider "mind" to be some kind of computation that could, in principle, happen on a computer.

I'm not too impressed by "computational" theories. As far as I can see, they tend to side-step the core question and propose some kind of hypothetical process that bears no obvious relationship to "mind" as we experience it nor, for that matter, much to do with actual brains.

The debate over the mechanism of consciousness draws a lot of attention away from the core issue, whatever the mechanism may be. These debates also tend to assume that consciousness is something that happens in the brain: an assumption that has become so "obvious" that it is rarely questioned. This is partly due to the "computational" theories, which picture the brain as a kind of computer. What else could it be? It is an uphill fight to wrench people away from this metaphor, but the clues are easy to find if you examine what human consciousness is actually like. It also helps to have a few decades of experience with computers. My experience with simulated people like Alexis and Siri reinforces my impression that "there is nobody home".

The more you learn about the brain (and we are just starting to learn about this), the more we learn about how the brain plays a central role in creating "mind", but the picture changes when we ask What the brain is for? What is it doing? No organ in the human body exists for its own sake. The brain is one of the largest and most energetically expensive organs in the body. What is it doing?

Suppose Rip Van Winkle came to life in 2019 after a 40-year sleep. We hand him an iPhone and ask him about it. After a few hours of careful investigation, he might guess that it's a tiny computer operated with a touch screen, which is kinda true. What he might miss is that the essence of the thing is its ability to communicate with the outside world. It's a phone (which Rip may understand) but it's "aware" of its location and its orientation. It's constantly chatting with the owner and the outside world, warning of upcoming radar, suggesting places to eat, keeping the user up to date on the news and assisting the owner to navigate the real world. The essential role of an iPhone is to "know" the status of the owner and to connect relevantly to the outside world. It's like a little "mind". More precisely, it's a tool that extends the power of the mind.  It gives us a clue about what a mind is.

My claim is that an iPhone may be a computer, but this fact hardly describes its role in the world or the role it plays in the owner's life. Similarly, whatever the brain may be doing, and whatever neuroscience may tell you about how it "works", you will not know what it is for, how it works and what benefit it bestows on the owner. In fact, the role of the brain resembles the role of the iPhone. It "knows" about its internal state, the location of the owner. It handles inbound and outbound messages. Unbidden, it alerts the owner to relevant local information and opportunities and so forth. Subjectively, all these things add up to what we call "mind"*. The brain's role in creating mind is undisputed but, like the iPhone, that role makes no sense if we ignore the role of the outside world, the needs of the owner and the interests of the owner in participating in society by personal messages and general information. You may say that the brain creates consciousness but the consciousness is not "in" the brain. The brain strikes a match which lights a fire that joins in the conflagration that is the shared experience of all human society. Participation in this conflagration is what it feels like to be conscious.

The way that all that happens in the brain is still a huge mystery. It may not even make sense to ask why it feels the way it does (the "hard problem"). It is, however, quite clear to me that we will never understand consciousness by ignoring everything that goes on outside our brain. In my view, we can learn a great deal about "mind" by exploring the parts of "mind" that are wide open for investigation, such as language, memory, perception and decision making. I see the mind in two ways: mind in the world and world in the mind. By studying the world itself, we discover the mind that creates and "models" the world. We can also study the "mind" (especially the brain) as an object in the world.

It may turn out that the brain is, after all, doing a kind of "computation". It seems to be doing other things that computers do, such as retaining memory, sensing the body and the world, controlling a "puppet" body and so forth. All this is appropriate to any kind of brain - the brain of a worm, for example. But we don't want to stop there. We are interested in the mind of human beings. Human minds do things like write symphonies and build space ships. That's the part of "mind" that interests us. That's the phenomenon of mind that is interested in itself.

My dog is very smart. She has a brain that follows the same mammalian architecture of my own. Her brain does all the kinds of "brain things" that I mentioned above. The "computational" power of her brain is probably not orders of magnitude different from my own. But she doesn't know she's a dog, nor is she curious about it. It would certainly be interesting to know all about how her brain works and what kind of a "mind" she has. This would certainly tell us a lot about how my own brain works. But it would hardly tell me much about my mind, which seems to participate in all human experience.

It's natural to think of "mind" as something that arises in the brain due to the complex physical connections between neurons. That's kinda like a computer, isn't it? Perhaps we need a different metaphor. Maybe something based on 21st-century computers, not the computers of 1960. The Internet is created by connections between multiple "hosts" - usually computers. These connections need not be physical (think cell phones and WIFI). The way they are connected is irrelevant to the way they work and what they are for. Most of these hosts are in the business of communicating with other hosts, usually for the purpose of sharing information. Similarly, our "minds" are connected to other minds through speech (sound waves and marks on paper) and many other indirect ways. Breaking these non-physical connections produces a serious degradation in the function of "mind", like turning your computer into an old fashioned "stand-alone" machine with no Google, no Email etc. A brain that is never "connected" to the outside world or other minds is a baby without much of a mind at all. You may choose to call it a "mind", but it is hardly the kind of "mind" we wish to know about. Not the kind of mind you and I have.

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* Of course, the "mind" is more than what is hinted here. "Consciousness" is a faculty of mind but the mind is far more than that. In fact, it seems that most of what "mind" does operates on an automatic and unconscious level. When considered in detail, much of this operation slips out of the "computational" model, but that's a topic for another day.

Reductionism

Descartes is the poster-boy for the method of "reductionism", which I think of as "Math Envy". This is the idea that you can build up all knowledge from simple principles. These days, we pretend to start with Quantum  Mechanics, yet we are awarding Nobel Prizes for people who make "baby steps" from Quantum Mechanics to the chemistry of Hydrogen. The fact is that reductionism is dead. There is no path from "simple" to "complex". We need to start somewhere else. That's good news, since it turns out that we all know a Hell of a lot more than we thought we did.

It turns out that we can start with what we all share and what we know: the fantastic and virtually limitless capabilities of the human mind. We don't need to "boil it down" to something simpler, or "explain" it in terms of chattering neurons. We learn very little about our minds by comparing them to the "minds" of chimpanzees, cats and frogs. If we assume that our minds are "nothing but" two pounds of meat on our shoulders, we succeed in explaining almost nothing while ignoring almost everything we know about our minds from first-hand experience.

The most cogent attack on reductionism I've seen comes from Nobel Prize winner Robert Laughlin: "A Different Universe: Reinventing Physics From the Bottom Down". Laughlin is not commenting outside his field here. He has first hand experience of how we actually figure out what is going on in the invisible world of Quantum Mechanics. His point is that we infer properties of the "small" world from observations in the everyday world and not the other way around. He provides example after example of the fact that we always fail when we attempt to "explain" the whole in terms of the parts. This applies as we climb from simple to complex going from Quantum Mechanics => Physics=> Chemistry => Biology. At each new level, a whole new universe of "emergent" phenomena emerge. Laughlin makes the case that there is a natural barrier between these levels. It's not just the way humans partition the world into University departments. Each new level of complexity is characterized by chaos, non-linearity and a whole new class of organizing principles.

If Laughlin is right, this turns all of Science on its head. Since Descartes and before, the project of Science has been to break down phenomena into the simplest pieces, study the pieces and bring it all together to understand the whole. It just doesn't work [2].

I hope I'm not being unfair to Dennett in guessing that, in spite of his attempt to present himself as a knowledgeable observer of Science, Laughlin's book would be well beyond his ability to comprehend. You need to "weigh a few electrons" in the lab to get what Laughlin is talking about. There is a good reason why it takes a thousand physicists and the biggest, most expensive machine in the world to "discover" the Higgs Boson. It turns out to be exponentially difficult for Quantum Mechanics to "explain" itself in detail, let alone explain simple chemical phenomena, such as the eleven different ways water crystallizes into ice.

[1] It is often forgotten that the ability of Europeans to think in anything like a logical manner was relatively new in the 17th century.  The Moors from Spain  in the 11 the century, resulting in the rediscovery of the Greeks philosophers. Before this, Europeans were not in possession of anything we would call Mathematics or logic. It took centuries to shake off the dead hand of theology and absorb the logic of the Greeks and centuries more to advance it. Progress beyond the Greeks started with Galileo and blossomed with Newton, a contemporary of Descartes. Seen from this perspective, both Newton and Descartes were still in the thrall of "Math Envy", following from the fact that the only thing they "knew for sure" came from Greek Geometry, its axioms and proofs. At least in the popular imagination, Mathematics is the ultimate reductionist discipline.

[2] Stanford's Robert Sapolsky gives an entertaining lecture on reductionism in psychology.

[3] Hofstader provides a devastating attack on reductionism in "I Am a Strange Loop", ironically taking issue with his close friend, Daniel Denett, the poster boy for reductionism. A close read of "Strange Loop" will reveal a further irony: Hofstader takes for granted that, in reality itself, the wriggling of atoms ultimately (in principle) accounts for what we experience as "mind", except the account is irrelevant and useless. He goes to great lengths to convince us that a "higher level" way of seeing things "makes sense".

Deep down, a human brain is a chaotic seething soup of particles, on a higher level it is a jungle of neurons, and on a yet higher level it is a network of abstractions that we call "symbols."

Thus, he still clings to the idea that "out there" in the universe, physics is more "fundamental" than psychology. To let go of reductionism, one must finally accept that "emergent" phenomena are genuinely new and cannot be explained in simpler terms, even "in principle".