Conversations: Iain McGilchrist, MD

 

SYNOPSIS

 

Emily speaks with psychiatrist-philosopher Iain McGilchrist about his book The Master and His Emissary, which explores the relationship between our brain’s right and left hemispheres and how they structure our understanding of the world.

 
 
 
 

GUEST

 

Dr. Iain McGilchrist is a psychiatrist, neuroscience researcher, philosopher and literary scholar. He is a Quondam Fellow of All Souls College, Oxford, a Fellow of the Royal College of Psychiatrists, and former Consultant Psychiatrist and Clinical Director at the Bethlem Royal & Maudsley Hospital, London. He is best-known as the author of The Master and his Emissary: The Divided Brain and the Making of the Western World (Yale 2009), and The Matter with Things: Our Brains, Our Delusions and the Unmaking of the World (Perspectiva, 2021).

 
 
 

RESOURCES

Mentioned in the episode:

 
 
 

CREDITS

Hosted by Emily Silverman

Produced by Emily Silverman, Sam Osborn, and Carly Besser

Edited and mixed by Sam Osborn

Original theme music by Yosef Munro with additional music by Blue Dot Sessions

The Nocturnists is made possible by the California Medical Association, and people like you who have donated through our website and Patreon page

 
 
 

TRANSCRIPT

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The Nocturnists
Conversations: Iain McGilchrist, MD
Episode Transcript

Note: The Nocturnists is created primarily as a listening experience. The audio contains emotion, emphasis, and soundscapes that are not easily transcribed. We encourage you to listen to the episode if at all possible. Our transcripts are produced using both speech recognition software and human copy editors, and may not be 100% accurate. Thank you for consulting the audio before quoting in print.

Emily Silverman
You're listening to The Nocturnists: Conversations. I'm Emily Silverman.

In the summer of 2021, I was invited to Galway, Ireland to speak at a conference called dotMD: A Festival of Medical Curiosity. And I was sitting in the audience at this conference, and onstage appeared this man in, I think, a tweed blazer. It may not actually have been a tweed blazer, but I feel like spiritually it might have been. But there was this man, Iain McGilchrist, who delivered this interview about the brain and the nature of reality that just kind of blew my mind. And so after I saw him speak, I rushed up to him and invited him onto the podcast, and he was kind enough to agree. Several weeks later, we did the interview. In my mind, I like to imagine Iain, sitting by the fire in his home in the Isle of Skye and toiling over his manuscripts.

Dr. Iain McGilchrist is a psychiatrist, neuroscience researcher, philosopher, and literary scholar. He's a Quondam Fellow of All Souls College, Oxford, a fellow of the Royal College of Psychiatrists, and former consultant psychiatrist and clinical director at the Bethlem Royal and Maudsley Hospital in London. His two books, The Master and His Emissary and The Matter with Things, are very, very well researched, very dense, but also completely and utterly fascinating. And a lot of his work recently has been looking at the functional asymmetry of the human brain. So in other words, the right hemisphere and the left hemisphere, how are they different? How do they see and process the world differently? And how do they work together? And the thesis of his argument is that the right hemisphere, which is the one that sees things as alive and whole, is the master. And the left hemisphere is really just kind of like the computer, or the emissary, of the right. But we in society have become confused and started to think that the left is the master, and that very fact is what leads to the downfall of civilizations, including the one we live in today. Not to get too grim. And I think as you'll listen, you'll see that the interview ends on a hopeful note. But just such an incredible body of work. I love this conversation. So before I sat down to chat with Iain, I asked him to read an excerpt. Here's Iain.

Iain McGilchrist
"This book is an attempt to convey a way of looking at the world quite different from the one that has largely dominated the West for at least three hundred and fifty years. Some would say, as long as two thousand years. I believe we have systematically misunderstood the nature of reality, and chosen to ignore or silence the minority of voices that have intuited as much and consistently maintained that this is the case. Now we've reached the point where there's an urgent need to transform both how we think of the world and what we make of ourselves. Attempting to convey such a richer insight is the ambition of this book. We have been seriously misled, I believe, because we have depended on that aspect of our brains that is most adept at manipulating the world in order to bend it to our purposes. The brain is importantly divided into two hemispheres. You could say, to sum up a vastly complex matter in a phrase, that the brain's left hemisphere is designed to help us apprehend, and thus manipulate the world. The right hemisphere to comprehend it, see it for what it is. The problem is that the very brain mechanisms which succeed in simplifying the world, so subjected to our control, militate against a true understanding of it. Meanwhile, compounding the problem, we take the success we have in manipulating it as proof that we understand it. But that is a logical error. To exert power over something requires us only to know what happens when we pull the levers, press the button, or alter the spell. The fallacy is memorialized in the myth of the sorcerer's apprentice. It is hardly surprising, therefore, that where we have succeeded in coercing the world to our will, to an extent unimaginable even a few generations ago. We have at the same time wrought havoc on that world, precisely because we have not understood it."

Emily Silverman
So, Iain, before we dive into the topic of your two magnum opuses–opi? I don't know what the plural is of magnum opuses. Before we dive into that, tell us a little bit about why you decided to become a doctor because a lot of our audience members are doctors, nurses, and healthcare workers.

Iain McGilchrist
Yes, I did it in a way which, certainly in Britain, would be unusual. The normal way for people to become doctors in Britain is when they leave school. If they've got the right exams, at a certain level, they may be accepted directly into medical school, so age 18 or 19. I, however, started medical school at 28 because my lifelong interest has basically been philosophy. And, to cut a long story short, I studied philosophy and literature at Oxford and then got the Prize Fellowship–and it only exists at this one college at Oxford, there isn't anything anywhere else like it. And, effectively, what it is...you sit in exam for three days and if you get accepted, you can do what you like. So I went off into science, I learned Russian, I read a lot of philosophers, I did all kinds of things. And, in the course of that, I wrote a book about why I didn't think that the way in which we study academic literature was right, that it denatured it, effectively analyzed it to pieces, and lost hold of the very things that were important in it. And I thought this had to do with the mind-body problem. But I thought that philosophers tended to approach the mind-body problem from a much too disembodied angle. And I thought I need to do this in a more embodied way.

And right at that time, Oliver Sacks' famous book Awakenings had come out. And there were two things about it that struck me. One was how he managed to make general points by going deeply into individual cases. So there were real studies of individual people who are alive on the page. But through that, he was able to draw general conclusions about the way the mind and body work. That was the first thing. And the other was simply that he was able to bring together in this exactly what I was interested in: What happens to the person when something goes wrong with their body, especially their brain? And I thought, well, I need to study medicine and become somebody like Oliver Sacks. That was what I naively thought.

And so I did medicine, as I say, starting much older than all the others. They would say, "How old are you?" And I would say, "28." And they'd all go, "Oh so brave. You've got one foot in the grave already." And it was wonderful because I spent 10 years in the humanities. And so, instead of finding anatomy a terrible bore in the labor, I thought, “How wonderful.” There are facts here that are right or wrong. You can get the insertion point of this muscle right, or you can get it wrong. I also thought how incredibly beautiful it all was. I remember the dissecting room, seeing a slice through a man's head. And there was the cerebellum revealed in all its beauty. And I thought, even an ugly person have one of those inside them somewhere. So I absolutely loved my medical training. I found everything in it seductive. And as I went through all the different specialties in training, I'd think, "Yes, I could do this...even intensive care or anesthetics." But in fact, my real aim and my love, my interest is always in the overlap between neurology and psychiatry. And so that's eventually where I ended up.

Emily Silverman
And along the way, you became interested in the way that the brain has an asymmetry to it. And so many of our listeners have been to medical school, have taken neuroanatomy classes, but they also might be a little bit rusty. So do you mind just reminding the audience...talk about the two hemispheres, the corpus callosum. And then in the book, you also go into these very subtle physical asymmetries in the brain. So explain that to us.

Iain McGilchrist
The first thing was some philosophical questions. Why, if the brain is all about making connections–that's what it basically is, a master of interconnections–and its power appears to be proportionate to the number of connections…Why would it be divided right down the middle like this? And why, over evolution, would the corpus callosum–the band of fibers at the base of the brain that connects the two hemispheres–be getting relatively smaller over mammalian evolution rather than larger? And why is the brain asymmetrical? The world is not in some clear way asymmetrical, nor is the skull. So how is that? And why is it that a lot of the traffic across the corpus callosum is actually inhibitory? So that set up a sort of vision that something was odd here. Our assumption that the brain just works together as a unit can't be right. Why was it separated? Why was it actually asymmetrical? And why was it careful about what it communicates?

Emily Silverman
Yeah, on one side, it's actually sort of larger in the front. And then on the other side, it's larger in the back, can you just briefly summarize these nuances to the physical asymmetry?

Iain McGilchrist
Yes. By the way, none of the things I've just mentioned was talked about at all in medical school. And in fact, I heard very little about the right hemisphere at all. It was all about the left hemisphere and how important and brilliant it was, which turns out on 30 years of research to be completely untrue. But it had been mentioned in medical school that the left hemisphere was broader. What wasn't mentioned is that the single greatest asymmetry in the brain is the fact that the right hemisphere is broader in the frontal region than the left hemisphere. This is the most obvious asymmetry. Now they said, well, the reason the left hemisphere is broader in the posterior region is because it is to do with language and language is very important. Which is fair enough, except that there are problems with that. For example, orangutans and gorillas have it, but they don't have language–they can't be taught language. And we know that from endocasts of skulls that primitive humans were already showing these asymmetrical enlargements, although we think they didn't have language. That was intriguing. And there's asymmetry which shows the right hemisphere jutting forward and being broader in the front and the left hemisphere jutting backwards and being broader towards the back. This is known as Yakovlevian torque after Yakovlev who first described it. I thought it was rivetingly interesting.

And perhaps I should just say that I spent some time doing neuroimaging research at Johns Hopkins. And there we were looking at asymmetry in the brain of schizophrenics. And what again, is not often talked about is that in schizophrenia, there is an absence of the normal asymmetries. And the normal brain has these asymmetries. The brain of the schizophrenic subject either lacks the asymmetry altogether or has it reversed. So this is interesting, partly because those areas have involved the role of...part of these asymmetries are gathered together in what one calls heteromodal association cortex, which is exactly the sort of...serves the functions that people with schizophrenia find hard. They have problems in those areas to do with understanding what other people mean, reading their faces, understanding emotion, being able to pass language, and produce language in an orthodox fashion. So all of this was very interesting, and my colleagues were very solicited. I had a lovely man who was my mentor, Elwin Leishman, and he said, "Don't go into that hemisphere thing. Nobody will take you seriously. You've got a promising career ahead of you. Don't ruin it."

Emily Silverman
So let's get into the functional differences a bit because I think if you just pulled someone off the street and asked them, "What does it mean to be left-brained or right-brained?" they might say, "The left side is linear, logical. The right side is more improvisational, free-associative." But you have a much deeper and more nuanced understanding of these left and right brain differences. And I'll just summarize briefly. You talk about how the left brain has a narrow beam, sharp, focused, attention that exists for the purpose of manipulation of the world, whereas the right side is more open and stays vigilant and is keeping an eye on how things fit into the bigger picture. So, I don't know if that was a good summary. But maybe you could elaborate a bit on both of those and help us understand what does it really mean to be left or right-brained?

Iain McGilchrist
Well, it's of interest that every neural network that we know, going right down through the brains of the tiniest creatures, but going even beyond that, to the most ancient neural network we know–700 million years old of Nematostella vectensis, a kind of sea anemone that's still extant–the neural networks are asymmetrical. All neural networks that we know are asymmetrical. Why? And it seems that this is to solve a conundrum that's very important for survival. That is, to be able to pay attention in a very narrowly targeted way to a detail that you want to grab and get. For that, you need fine manipulation. You need to know exactly what you're dealing with. There are no surprises. You're getting food, you're getting a twig, you're killing that animal. Whatever it is, you're doing something that is of utilitarian interest. But if that's all you're doing, you will not be aware of the predator who is about to get you while you're trying to get your own lunch. And you also don't see the whole of your shoal of fish or swarm of birds or whatever that are surrounding you and to which you belong. So all creatures need to be able to pay this piecemeal targeted, sharply focused attention to detail, but also to pay a much broader sustained vigilant open attention without any kind of preconception of what it's going to be that it will pick up.

What this results in is actually a different kind of a world. Because if you see a world that's made up of little bits that you're grabbing, that are static, because they've been frozen in the glare of your "get it and grab it" attention too so they're isolated, they are static, they are decontextualized, they are disembodied. They tend to be abstract, there's little that's unique about them. They're just exemplars of food, twig, whatever it is. And effectively, this builds an inanimate picture of the world where everything moves because we give it a shove. It's exactly the world as a machine. But the right hemisphere sees that, actually, nothing can be understood once it's taken out of its context. That changes, it is what it is only where it is in that context. And it's connected to lots of other things. It's not in isolation. That it contains information that is not explicit. Much of the stuff that is important to us is not the kind of stuff that can be stated explicitly and fed into a computer. It's assessing tiny changes in your interlocutors, facial expression, body language, tone of voice...all the things that make life worth living: love and poetry and religion and spirituality and music. It sees an effectively animate world. And interestingly, you can, using TMS, you can knock out areas in one hemisphere at a time. And if you knock out the right hemisphere, you find that people describe things they would normally describe as animate, like machines. If you knock out the left hemisphere, they describe things that they wouldn't normally think of as animate as alive, like the sun.

Emily Silverman
I know in the book, there's this idea, like you said, of the bird who wants to reach out and grab the twig. And that's like the left hemisphere, "I'm grabbing this." And then the right hemisphere would be looking around and, "Is there a predator?" and monitoring the environment. But there's also other examples. And there's like a metaphorical kind of grabbing. Like you even talk about how just language itself is a metaphorical way of grabbing a concept.

Iain McGilchrist
Generally speaking, the left hemisphere has reduced whatever it is to a concept. The right hemisphere has direct experience. We know this, that when the subject is confronting something new, their right hemisphere is taking in the newness of it. But once the left hemisphere has got hold of it, it says, "Oh, I see. It's one of those," and puts it in a category. So that has an effect. And this business about the implicit versus explicit takes us to what you're saying about metaphor because a metaphor...the whole point of a metaphor is that it's not a literal statement. So the point of saying that Churchill was a bulldog depends on the fact that Churchill was not actually a bulldog. He was a human being. So but what you're saying is, there's something there that by bringing these two concepts together, the man and the dog, something can be said.

So poetry works like this all the time. It's often setting up metaphors that have many resonances, half a dozen different resonances. If you think of a simple one, like the rose, it's a bit heartening, but it has so many meanings of beauty, of something that can prick you, of the color of blood, of so many things, the heart, so on. So metaphor is a very rich and living way to use language and the left hemisphere doesn't get it. So it does not compute and it sees a metaphor as simply a lie. Because, "Wait a minute, Churchill is not a bulldog." But it's not just a lie. It's not like saying, "Churchill is a bookcase." It's also true Churchill is not a bookcase, but it doesn't make it a useful metaphor.

So it's those links that are made implicitly, that are not their humor, and irony, and sarcasm, and kind of all the things we expressed. All this is not understood by the left hemisphere, which is something more like...I resist the image of the computer in comparison with the brain because the brain is only like a computer. But in some ways, the left hemisphere behaves a bit like the right hemisphere's personal computer. It understands the world and the scene. It gives it stuff to compute, and it does it very efficiently. And it then doesn't really understand what it's computed, but it gives it back to the right hemisphere, which can resituate it in the context of the whole. So you've always got this interesting interplay between one that oversees that the whole, and one that can deal with the parts. But we must allow that analysis of the parts not to end there, but we take it back into the enriched whole. And perhaps it would just help to use a map over here, that of a pianist who learns a piece. First of all, he or she is attracted to the piece. And that's the right hemisphere. It's a new thing, it understands it, it's great. It wants to play it, trying bar 28 is a hellish piece of fingering that's got to be gone over time and time again. So takes it apart, it analyzes it in terms of, "Oh I see, here we return to the tonic," and so on. But when the person goes back on the stage to give a performance, they must actually forget all of that. This doesn't mean that it was a waste of time. It was very important at one stage. But now all that must be just part of giving an enriched performance of the whole. And that's a good image of the way we can use the hemispheres in life.

Emily Silverman
Yeah, you talk about this idea of the parts and the whole. But there's also this idea of the map and the territory. And at The Nocturnists, one thing we do is we help healthcare workers stand on stage and tell their stories in front of the audience. And helping them to tell a successful story that lands is actually a really difficult thing, I think, especially because clinicians tend to be so in that left hemisphere. And one thing we've noticed is the difference between telling a story more like you're reporting something that happened, like you're giving a representation of a real experience that happened, but you're not having the real experience, you're just reporting it out or explaining it. And then making this switch into telling the story in such a way where you're actually having the experience onstage, as you tell it. And that's the more embodied way of performing. And that's the way that really hooks the audience in. And so, in addition to this parts and whole, can you talk to this map and territory? Like the difference between having an experience and representing an experience?

Iain McGilchrist Absolutely. There was a man called Alfred Korzybski, who actually made famous this distinction between the map and the terrain. And I think it's an enormously important one. Because we know that the first take, if you like on experience, is through the right hemisphere. But almost instantly, whatever that is, is transferred to the left hemisphere, where it becomes a representation, which literally means present again, after the fact when it no longer actually is present. So it's presencing, to use a technical term in philosophy in the right hemisphere, but it's actually represented in the left hemisphere. This is the difference between the living, which is...you get the living presence, and you communicate with it. It's a reverberate of relationship, and the kind of dead map or diagram of it, which is the representation. And this is such an important thing to bear in mind throughout one's experience of life. Once you see it, it crops up everywhere. And the right relationship here is, for that scheme, or theory, or diagram, or map, or whatever you like to put it as in the left hemisphere, is only a tool that may be helpful for a while and then discarded by the right hemisphere, which is actually able to understand far more than the latter. So that, you're seeing these things in a much more subtle and nuanced context, not just in a "machine says," "computer says 'no' or 'yes'", and, "it's got to be like this." But in life, it's very rarely like that very few things are certain very few things are final. Science is, in fact, the story of the continually mistaken.

Emily Silverman
You mentioned neuroscientists and neurologists. And earlier you mentioned different brain diseases or brain lesions like strokes, for example, which knock out parts of the brain and then show us how these hemispheric differences might declare themselves through this, you know, pathology or through this absence. So I'm wondering what are your favorite examples of disease states or abnormal states?

Iain McGilchrist
One of the marvelous developments in medical technology is–I've already mentioned–is that using TMS, transcranial magnetic stimulation, you can either suppress or enhance the activity of the underlying cortex in an entirely painless process using a magnet. Now if that's possible, you can actually simulate a lesion temporarily in a person for 20 minutes. And then they go on their way, and there's no damage done. So out of that literature, you see the most extraordinary things. I mean, perhaps a general remark is worth making at the outset about the values of the two hemispheres. And when they go missing, which is if you ask the carers for people who have had a left hemisphere stroke, "What is most frustrating for them and for their loved one or their charge?" They say things like, "He finds writing difficult," or, "He gets frustrated when he's reading," or something like that. Fine. Yeah, okay. But if you ask carers for somebody who's had a right hemisphere stroke, what's frustrating, they'll say, "He's a completely different person. He doesn't seem to understand what I mean when I say things. He doesn't get the meaning of ordinary discourse. He has no empathy anymore." Things like that. So it's a really core to being, you know, a functioning human. You can get by without language. And people with left hemisphere strokes understand perfectly well what's going on. They may not be able to articulate it. But with the right hemisphere, although they can articulate they, you know...which means they're harder to rehabilitate.

But let me just give one of the two of the most obviously, extraordinary examples. One has to be the business of neglect and the consequences of neglect. Because the right hemisphere pays a broad, open attention and the left is narrowly targeted attention to the right hemispace, in which its tool, the right hand, is doing its work, grasping, and getting, and using tools...After a right hemisphere stroke, are the subject is dependent on the left hemisphere, very often, they only see the right half of space. And they know that there must be another half of space. It's not that there's anything wrong with the optical system in itself. You know, that is registering, but they don't attend. And so, they will read only the right half of lines of a book, they will eat only the food on the right half of the plate, they will not respond to somebody who's standing to the left of midline. And actually, these are not unusual. I've seen them many times in clinical practice. I'm sure every neurologist and probably everybody who's been through medical school training has seen patients like this, who simply deny that there's either that they've got a left side of their body, or if they're shown if there's anything wrong with it. You say to them, "Is there anything wrong with your body having had the stroke? Is everything working?" "Yes, fine, doctor, thank you." And you go, "Oh that's very good. Any problems with your left arm, for example?" "No, no, no, it's fine." "Can you move it okay?" "Yes, sure." "Can you show us?" And they go, "There." You know, and actually nothing moves. And if you get hold of the hand and bring it round right in front of them, so they can't avoid it, and say, "Move that," they'll say, "Oh, that's not my hand, that belongs to the man in the next bed." Or, "That's your hand doctor, not mine." Or, "It's my mother's hand." These are not people who are psychotic, but for the moment, they totally left touch with reality.

Now, if you have the other stroke, a left hemisphere stroke, your right hemisphere is still functioning, and it gives you the whole picture. But in the case, as I say, of right hemisphere subjects, you get all kinds of phenomena that are bizarre, including some of the things I've mentioned–reduplicative paramnesias and things like that. But you also get this sense that people, including themselves, are not real, but are representations of people. Remember, the left hemisphere is the hemisphere of representation. So they will think that the nurses on the ward are not real nurses. They are actually machines that are made to look like nurses, or AI that has been made to look like nurses, or zombies, or just people who are play acting for their benefit. And they may think that they themselves are either dead, or dying, or are zombies. So you get this hyper-mechanistic, inanimate vision of the world, which is fragmented, two-dimensional. They say, "Sometimes I'll get a feeling that if I could just put my hand up to the top of the scene in front of me, I could pull it down, and I'd reveal if it was just a single sheet." So the depth, which we normally get from the right hemisphere, both depth of space, depth of time, and depth of emotion, is absent for them. And instead, they're in a slice of time, in a tiny piece of space. And with shallowness of emotion, all the depth has been drained. And that is a typical right-left hemisphere difference.

Emily Silverman
So the title of your first book is, The Master and His Emissary. Make the case that the right hemisphere is actually the master, as you said, in some ways, the left hemisphere is the computer that serves the right. And then help us understand why in the world have we become confused, and started to treat the left as the master.

Iain McGilchrist
The title The Master and His Emissary, and the book has the subtitle, The Divided Brain and the Making of the Western World. So in the second part of the book, we go on to look at the way this balance has shifted over time. The idea of that comes from a very simple tale, that there is a wise spiritual master who looks after a community so well that it flourishes and grows. And after a while, he realizes he can't look after all the business of this community himself. But he also realized there's something more important: that he must not get involved with certain aspects if he's to be able to maintain his overview of the whole. So he appoints his deputy, his ambassador, his emissary, to go about on his behalf and do the admin, a sort of high-level functionary. And he chooses somebody who is intelligent, but unfortunately, he's not intelligent enough.

There's a phenomenon in psychology called the Dunning–Kruger effect, which means that the more you know, the more you realize you don't know. And the less you know, the more you think you know it all. And unfortunately, the left hemisphere, knowing literally very much less than the right hemisphere, give masses of evidence that from neuroscience studies. In the book, the left hemisphere thinks it knows everything and thinks it's the master. And so it goes about his business going, "What does that master know? He's sitting back at the temple, sitting on his ass, meditating seraphically. He doesn't really know anything. I'm the one that knows everything and does all the hard work." And so he pretends to be the master. But not knowing enough, fatally, he allows things to fall to wrack and ruin. And that's the end of the master of the emissary and the community.

What I definitively show is that the left hemisphere is less able to take in information of the world and make sense of it. It is actually less intelligent, not just emotionally and socially, which it very obviously is, but it is also cognitively less intelligent. Its attention is less fruitful and less comprehensive. Its perceptions are poorer. Its ideas formed on attention and perception, its judgments, in other words, are more likely to miss the target very widely. Effectively, when we are in hock to this left hemisphere, and we're doing its bidding, we are on a track to ruin. We are basically committing suicide.

So what I showed in the second half of my older book from 2009, The Master and His Emissary, is looking at Western history since the time of the ancient Greeks, that three times as we have to have grown up a flourishing civilization, which lasted for a few 100 years. But then, the urge in every case further towards the left hemispheres take before collapsing. So you see this wonderful fruitfulness of the way in which things work together at the beginning of the Greek eruption of fertility in the sixth century BC, which produce major steps forward in science, in maths, and in the arts, and drama, and music–and you name it–in lawmaking, in mapmaking, in astronomy...And the same thing, a wonderful richness, occurred in the Roman Empire around the dark, and again, at our renaissance, in which all these things flourished.

But quite soon, the propaganda of the left hemisphere, that it knows everything and knows it better, takes over to the expense of the right hemisphere. There are different ways of answering why this comes about. But perhaps one of the most straightforward is that, when you have an empire, your prime value becomes control: being able to keep that empire under control, to exert power over it, and to use the resources that are made available by it. And that is massively served by the left hemisphere. It is, in fact, the raison d'etre of having this division. The left hemisphere can get on with grabbing stuff, and manipulating stuff, and making up procedures, rules, algorithms. Whereas the right hemisphere is perceiving that things are much more complicated than that. Partly, when a society becomes larger than a small group of say, up to 70 or even 100-120 people, we no longer really know one another. And, so, we rely very much on public pronouncements, and public statements, and things that are written, and things now that are on the web, and so on. And in being able to put a point of view across, if you try to express the right hemisphere's point of view, you have a very difficult task. It's much truer than the left hemisphere's point of view. But the difficulty is that it's much more subtle.

And, so, many nuances have to be conveyed, which are very difficult, particularly in the error of the soundbite. There's usually something to be said on both sides of the argument, which the right hemisphere is much better able to see. The left hemisphere..."Make up your mind. Is it this or is it that?" It thinks in a very "either/or" way. And a lot of what it has to say it could seem contradictory. But, actually, to be able to show that you need to hold two points of view, each of them has something to be said for it, but aren't strictly speaking to be fused into one. That is a more difficult task to do.

So I think that what happens is in these larger societies, as empires grow and flourish, is that this kind of rationalizing public discourse takes over. And therefore the messages is that the right hemisphere would have given are fainter. And in our modern society, the very ways in which they would have come to us in the past have been neutralized or minimized or almost dismissed. One is the proximity to the natural world, which we know doesn't work like a piece of machinery. And we know that it has great value to people for their mental and physical health and their general well-being to spend time in nature; it reconnects them with something that tells them of something beyond this mechanical structure we set up as being the cosmos. Another would be social cohesion. People who live in highly cohesive groups share their lives with one another, share their meals with one another, worship together. This is known to produce much higher rates of mental well-being and physical well-being effects on heart disease and so on.

Emily Silverman
I believe in the book, you say that the left hemisphere tends to be more optimistic, and also more incorrect. So maybe as my final question, where are you on the spectrum of optimism to pessimism?

Iain McGilchrist
Good question. I'm enough and call myself a hopeful pessimist, which is to say that my assessment is that things are not going well. But I'm always hopeful. And I think there will be a great crash. I think that there will be losses of life. I think that civilization, as we now understand, it may not have long, actually. But that may be just another important cycle, that we're really doing such foolish things, that the world needs to be rid of quite a few of the people who are inflicted on it. And that something better and wiser may emerge from those who have...and I'm sure people will survive and may live in small groups and rediscover things that we've forgotten, skills and understandings, a kind of wisdom that we have discarded. So in all those senses, I'm not too pessimistic. But I also think it's very important to be hopeful. Apparently, I don't think that we can predict things. I think the people who make big predictions end up with egg on their faces. So I'm not making any hard and fast predictions here. I'm just saying this looks like a possibility worth considering that it may go that rather unfortunate way.

But more than that, hope is a cast of mind. And it can't be reduced to a conviction that everything's going to get better. That would be to trivialize hope. I think it's a disposition that says that you trust that everything, although the moment it does look hard to unravel and to understand its importance, that even the things that we think of now as negative, including great suffering, may ultimately–does ultimately–have meaning. It's not entirely pointless or meaningless. And if the world has meaning, and I believe it does...So that in fact, it's our job to discover that meaning not to invent it. It's sometimes suggested that we need to paint a pretty picture on the walls of ourselves to cheer ourselves up. But I don't think it's about that. Once again, it's about an encounter, a reverberative encounter with something other than ourselves, which I believe is living, beautiful, and complex, and is the cosmos into which we have emerged and back into which we will fuse at some point. And that it's looking to those things rediscovering, or in the sense of wonder, rediscovering beauty, rediscovering compassion and love. I think you could do much worse than have those as an aim to produce a better world both individually, and, well, for the whole of humanity.

Emily Silverman
I think that's a beautiful place to end. I have been speaking with Dr. Iain McGilchrist, philosopher, writer, thinker, and author of two incredible, incredible works of art and science and thought called The Master and His Emissary, and The Matter with Things. Iain, it's been a pleasure. Thanks so much for speaking with me today.

Iain McGilchrist
Thank you very much, Emily. It's been a pure pleasure for me too. Thank you.