Natasha Mitchell: From Bach's Chorale Prelude Ich ruf Zu Dir, Herr Jesu Christ, Andrei Tarkovsky opened his classic 1972 movie Solaris with it and my guest today uses it to reflect on the emotional and spiritual needs of the psyche.

Gone with the Wind, eat your heart out, today on Radio National Summer I've got a grand and provocative saga of vast proportion for you. Vast, but also deeply intimate; because it's cast across the history of Western civilisation but also inside the crevices of your brain. Dr Iain McGilchrist started out as a scholar in English literature and philosophy; his second career though saw him become a leading consultant psychiatrist and clinical director at the Bethlem and Maudsley hospital in London.

His latest book is something of a magnum opus, you can tell by its title, The Master and His Emissary: The Divided Brain and the Making of the Western World. At its heart is a warning about the way we live. 'There's a reason we have two hemispheres of the brain,' he says, 'it's because we need both versions of the world.'

Well Iain McGilchrist, welcome to the program, thanks for joining us from London.

Iain McGilchrist: Thank you very much.

Natasha Mitchell: Your account, Iain, of where western civilisation has arrived at is a dark one, it's a pessimistic one. You suggest that we, and these are your words, 'occupy an increasingly fragmented, decontextualised world marked by unwarranted optimism mixed with the feeling of emptiness.' This is a dark conception of the world -- what prompted you to turn to the brain for an explanation when others might instead turn to social and economic shifts?

Iain McGilchrist: Yes, I don't think that it was really that I was turning to the brain for an explanation of those social changes, the changes in our culture and the structure of our civilisation even, but in fact that whole perspective that there's a greater reality by accounting for things at the brain level is one that I would be sceptical of. Instead it's more trying to suggest that there are two broad takes on the world if you like, and that in what I learned about differences between the hemispheres suggests that these actually underwrite two competing ways of being in the world and thinking about the world, only one of which we seem capable of entertaining these days.

Natasha Mitchell: And that's the left hemisphere view. But for you the brain has very much played a role in creating the world we occupy. It doesn't just experience the world, it generates it.

Iain McGilchrist: That's right, that my idea is that the world is something that isn't exactly given before we experience it but also isn't just something our brains or minds make up. It's a coming together of whatever it is outside of us with our minds. And that in the process of the two meetings there is a sort of what I call between-ness which brings things into being. And depending on which mode of attention we bring to bear on the world, a different sort of world will come into being.

Natasha Mitchell: Let's come to the title of this book, The Master and His Emissary, it draws from a lamentation on your behalf about the status of modern society.

Iain McGilchrist: Yes, it's very loosely based on a little story in Nietzsche about a wise spiritual master who is the head of a small community which flourishes under his care and grows in size to the point where he can't actually look after it all himself so he needs to have an emissary that he trusts. And his most trusted and gifted emissary is sent off to get on with business in the further flung parts of the domain. And I think an important point is that the master realises he can't actually get involved with that and can't know those things. In fact not only can't but shouldn't know what's going on there, he must deputise that to the emissary otherwise it would jeopardise what he is able to do.

And I think this is in a way an image of what...the relationship between the right and the left hemispheres. The right hemisphere sees a great deal but in order to refine it and to make sense of it in certain ways in order to be able to use what it understands of the world and to be able to manipulate the world, it needs to delegate the job of simplifying it and turning it into a usable form to another part of the brain. And if that brain, if that part of the brain was actually attending to it in the same way as the other part, they wouldn't be able to achieve this double act, if you like.

And in the story what happens is that the emissary feels that he's actually the one who is doing all the hard work here and doesn't really need the master, who's just an irrelevance, and through his sort of pride and short sightedness the community collapses and fails.

Natasha Mitchell: So the emissary betrays the master and in this way you're seeing the master as the right hemisphere and the emissary as the left hemisphere in today's world.

Iain McGilchrist: Yes.

Natasha Mitchell: Now what's gone wrong with today's world?

Iain McGilchrist: The way that metaphor works in the modern world is that the right hemisphere, from all that we know of neuroscience, conceives the world in a certain sort of way which is primary and we mustn't lose sight of it. But the left hemisphere has a narrow, decontextualised and theoretically based model of the world which is self consistent and is therefore quite powerful. And it becomes more important in the modern world, it seems to have taken over, there seems to be a process whereby its vision has become the only vision and the vision that would be possible through the right hemisphere has been undercut and excluded.

There are a number of reasons why that might happen. The first is, as I say in the book, I call the left hemisphere the Berlusconi of the brain because it controls the media, it's the one with which we do all our talking and arguing. But also it's fascinating in looking at the way in which the two hemispheres mutually inhibit one another across the corpus callosum, the band of tissue at the base of the brain through which they're connected. And the function of the corpus callosum is to convey information but very largely to inhibit the other hemisphere from acting when one of them is active. So there's a constant reciprocal interaction between them. But the fascinating thing is that the left hemisphere is better able to inhibit the right than the right is to inhibit the left.

Natasha Mitchell: Right, so it is in a sense dominant.

Iain McGilchrist: It's dominant in that way, even though in terms of the importance of what it can tell us it's secondary. The other thing is the left hemisphere is a system, as I say, is self consistent in a simplified way.

Natasha Mitchell: So it can delude itself.

Iain McGilchrist: So it can delude itself that it knows everything, whereas I see the right hemisphere as seeing things that lie beyond what we ourselves can see. So it is all the time as it were grasping or trying to grasp, reaching out towards something that is beyond us.

Natasha Mitchell: And in this way you suggest that the right hemisphere is our bullshit detector, it's more in touch with reality. But on what scientific basis do you...

Iain McGilchrist: Well there's a lovely piece of research by Dennett and Kinsborne, two quite prominent neuroscientists. They asked the same questions to individuals with both their hemispheres intact and working; with just the left hemisphere functioning, and with just the right hemisphere functioning. There are ways of temporarily inactivating one hemisphere or the other, and what is extraordinary is that when completely false propositions are put to the left hemisphere it accepts them as valid because the internal structure of the argument is valid. So the individual who has previously said this can't be right says well that's what it says on this bit of paper.

The right hemisphere on the other hand cries out this can't possibly be right, I know from experience this isn't correct. And that's much closer to the position that we adopt actually when we've got both our hemispheres working. That's how we detect that this is most probably not right.

Natasha Mitchell: Let's come to the contemporary world, because I mean you think it's come about through what you describe as the unopposed action of a dysfunctional left hemisphere, that in effect we've entered a phase in cultural history where the left hemisphere has all the cards and looks set to win the game. Is that more than a metaphor in your mind?

Iain McGilchrist: Yes, I think it is more than a metaphor in that it's at least my very real conception and concern about the way our culture in the west is heading and I think it's shared by a lot of people; which is that it is a rationalistic rather than reasoned or reasonable and mechanistic model of who we are and of the world that we inhabit, which is based on a relationship of exploitation (the left hemisphere is there to help us use and manipulate the world) and has come to displace a sense of ourselves as in connection with the world and playing an important reciprocal role with one another and with the planet on which we live.

So I think it has a very real meaning for where we are heading now, both in terms of the increasing abstraction bureaucratisation and technicalising of our lives and the sort of paranoia in which we can't trust one another anymore and have to monitor absolutely everything, versus you know a richer and more inter-connected sort of vision of the world.

Natasha Mitchell: And this you cast as very much a left hemisphere way of framing our world.

Iain McGilchrist: Yes.

Natasha Mitchell: And viewing the world.

Iain McGilchrist: Yes. And one of the fascinating things is that if you look at what happens to people when they have a stroke in the right hemisphere, a very, very usual phenomenon is that people underestimate or even deny the extent of their disability. As I say in the book the left hemisphere is an eternal optimist, it constantly believes in itself to a degree which is unsound, and that means in terms of the patient that they may deny that they've got a paralysis altogether.

There's a nice little bit of research looking at people who -- again you can isolate the right or left hemisphere experimentally and ask questions -- and when people estimate themselves with their right hemisphere they are more realistic about themselves. When they estimate themselves with the left hemisphere they give an unrealistically optimistic assessment of their own skills and abilities compared with what other people would say of them.

Natasha Mitchell: If we think about the two hemispheres of the brain, I mean they've been heavily popularised: left brain/right brain. You suggest that they've been hijacked by management, trainers and advertising copy writers and I would add probably new age aficionados as well.

Iain McGilchirst: Indeed, the idea was that the brain was like a machine that carried out certain functions, and because there were two hemispheres there was twice as much computing power as it were, but we would compartmentalise things. So there was a story that language was in the left hemisphere, reason was in the left hemisphere and something like creativity and emotion were in the right hemisphere. That's a complete and utter....misconception of things. Every single brain function is carried out by both hemispheres. Reason and emotion and imagination depend on the coming together of what both hemispheres contribute. So that particular dichotomy is incredibly unhelpful and misleading and I keep trying to steer away from it, but there is still, nonetheless, fairly obviously a dichotomy.

I mean I begin by asking the rather simple question which I'm not aware really has ever been properly addressed which is you know if the brain is all about making connections why is it that it's evolved with this whopping divide down the middle?

Natasha Mitchell: An interesting question indeed. I mean nevertheless, even though we now understand both hemispheres of the brain are involved in all the activities of the brain, you make the case, Iain, that there is quite literally a world of difference between the two hemispheres of the brain.

Iain McGilchrist: Yes that's right, because I think attention is a very interesting thing, it doesn't sound like; it just sounds like another function of the brain. But in fact attention is a remarkable thing, it's the nature of attention determines what it is we find, and equally what we find determines the appropriate kind of attention to pay to it so it's a reciprocal process.

Natasha Mitchell: Your case here is that the left and right hemisphere attend to the world very differently so ultimately they construct a different world.

Iain McGilchrist: Yes, well we do know from lesion studies from every kind of neuropsychological information that the left hemisphere tends to adopt a narrowly focused attention which does bring into focus a very, very small part of the world. And we need that in order to be able to grasp things, the left hemisphere is not for no reason the hemisphere that controls for most of us the right hand with which we grasp things and the bits of language which make things precise -- whereby we say we grasp something.

So it's about that precision. And in birds and in animals the left hemisphere focuses on prey or on something that is there to be eaten, and the right hemisphere at the same time is keeping a sort of broad open attention for predators. And we know also that animals and birds use their right hemisphere for social interaction, not just of course with foes but also with kin, with con-specifics. So one of them is a sort of uncommitted and relational mode in which one is looking at the world in a broad sense for whatever it may contain.

Natasha Mitchell: That's the right hemisphere?

Iain McGilchrist: That's the right hemisphere and one sees oneself in relation to it, whereas the left hemisphere takes a very detached and precise view of something that we already know is important. Now if you put that sort of information together you end up putting together a lot of little pieces of information and you get a different sense of what something is from the mind that is able to take a much broader view.

Natasha Mitchell: Another way you describe the left hemisphere in the brain is an ambitious bureaucrat with their own interests at heart; it's a virtual bloodless affair, parasitic on the right.

Iain McGilchrist: Yes, I let it rip slightly in that phrase, there's a limit of course as to how helpful it is to anthropomorphise the hemispheres. On the other hand I would say there's no obvious reason why comparing them to human beings and after all each hemisphere is perfectly capable of sustaining consciousness for a human being; there's no reason why that should be a worse metaphor than the machine metaphor.

Natasha Mitchell: Yes, interesting. Psychiatrist and author Iain McGilchrist is my guest this week on ABC Radio National and Radio Australia's All in the Mind, I'm Natasha Mitchell and we're discussing the battle he thinks is being played out between the two hemispheres of the brain. The stage -- no less than the history of civilisation as we know it.

I mean let's head back in history, because you look at the present through the lens of the past. What you describe effectively, Iain, is a power struggle that's unfolded over time, over the last 2,000 years in fact, between the two hemispheres of the brain that's played out in the formation of western culture and its key transitions from the ancient Greeks to the present day. So let's dig in to that historical narrative, where does it begin?

Iain McGilchrist: Well I think it probably begins -- at least my understanding of it is that I can see it in the ancient world and there's a similar progression actually in ancient Greece, in ancient Rome and indeed from the Renaissance onwards in our own world. And that is, that for reasons that are complex and one can only speculate about, there appears to have been a quite sudden shift, an efflorescence of activities that are characteristic of both the best of the right hemisphere and the best of the left hemisphere working together in the 6th century BC in Athens. So you get a culture which is enormously productive across the whole field of humanities and science. But as time passes, and by the time the 4th century BC comes along, already there is a drift towards a more theoretical and conceptualised abstracted bureaucratic sort of view of the world. And so there's a tendency for things to move further and further towards the left hemisphere's conception.

This happens again in ancient Rome in the Augustan era there was a brief period where I see the best of the right hemisphere, the best of what the left hemisphere offers together producing an enormously rich mix which generates what we think of as the bequest of classical Roman culture to our civilisation. But again, within a couple of hundred years, things have drifted towards a more unwieldy and bureaucratic, power-hungry and militarised, very hierarchical structure.

Natasha Mitchell: Which you describe as a leftward shift in the brain as well.

Iain McGilchrist: A leftward shift in the brain.

Natasha Mitchell: And where does that impulse come from do you think?

Iain McGilchrist: Well I think it's an inevitable process which, because of the relationship between the worlds of the right and the left hemisphere produce, when the left hemisphere is allowed to conceive the world relatively independently from the right hemisphere -- which is initially something rather wonderful as long as it's in conjunction with what the right hemisphere gives -- it produces a very rich, productive and fertile and creative imaginative world.

Natasha Mitchell: Because if we think of the ancient Greeks it was a time of analytical philosophy but it was also a time of how you describe it as a greater empathetic engagement with the world.

Iain McGilchrist: Yes.

Natasha Mitchell: It sort of had a bit of both didn't it, the abstract and the empathetic?

Iain McGilchrist: Absolutely, yes and that's very much to simplify it but yes, we see aspects of what each of them in a specialised way produces, working together. But the right hemisphere contribution seems to decrease and the left hemisphere gains in confidence through its view, which one can see in aspects of Plato's philosophy, that he can account for everything in certain ways. You can find Plato eventually saying that astronomy is done by looking inwards by not looking at the stars, which you know is quite a remarkable thing to be saying. only a few hundred years after the first empirical scientists were observing the heavens and making very good and robust deductions from what they saw.

So that's the drift there and one sees the same thing happening in Roman civilisation and I see this happening also in our civilisation when, again, there is this sudden efflorescence of creative life in the sciences and the arts in the Renaissance, but with the Enlightenment there is a hardening up of the certain rather dogmatic and left-hemisphere-based view of the world, which we are still struggling with.

Natasha Mitchell: Are you giving the left hemisphere a bit too much flak here, I mean you seem to associate it with an absence of feeling, an absence of depth and context, but on the other hand, I mean the left hemisphere you also suggest lies at the basis of western civilisation. You know the great push to reason and rationality that was born of the Enlightenment, gave birth to modern science.

Iain McGilchrist: Well I slightly dispute that, I think modern science originated earlier than the Enlightenment and that's really what I'm saying, it was an enormously rich period in the 15th, 16th and early 17th centuries before the Enlightenment kicked in. And of course the left hemisphere is not devoid of feelings at all, it has its own range of emotions and the capacity to appreciate emotions. Interestingly anger is one of the emotions that is most obviously lateralised towards the left hemisphere, so it's not that it's able coolly to get on with science, I think that's a total misconception.

Natasha Mitchell: Which is relief, I'm glad it's a misconception.

Iain McGilchrist: Yes, exactly. Science is something much more wonderful than that, science is patient attention to things as they are, which means actually seeing them in context, and this was very much the way, the spirit in science from Bacon through to Goethe, but there is another strand in which it's become in a way decontextualised and dehumanised, which is a mistake in my view. So although you say I give the left hemisphere too much flak and in a way of course you're absolutely right, I'm trying to redress a balance. As I keep saying in the book nobody needs telling that rationality is important, it's bloody obvious really and nobody needs telling that the capacity to create sequential reasoning is a very important feature of the human mind.

But I think because it is so eloquent on its own behalf, it's neglected to allow us to perceive that there are other very important things that need to be combined with it and that's really the message. It's not that somehow the right hemisphere has got it all right and the left hemisphere has got it all wrong. That's another either/or black and white misconception which is much more typical of the left hemisphere's take on the world. The right hemisphere's take is broadly inclusive, as in the metaphor, the master knows that he needs the emissary; it's the emissary that thinks it doesn't need the master.

So my view is the right hemisphere is perfectly aware that it's a symbiotic relationship and when that works well, as it has done in periods in the west, it's a recipe that can't be beaten. What I say at the end of the book is to speculate as to why this doesn't seem to have happened to the same extent in oriental cultures.

Natasha Mitchell: Yes, that's a very interesting observation; because you're focused very much is on western civilisation here isn't it?

Iain McGilchrist: Well it is largely because of course that's what I'm familiar with and it's also the civilisation that seems to me to be presenting the world with a crisis at present. But it is interesting that in the last 15 to 20 years there has been a consistent and growing body of neuropsychological research asking far eastern people: Koreans, Chinese and Japanese to address problems, to make observations and then comparing them with the same problem-solving strategies and attentional strategies of people of western extraction.

And what one finds there is not that in some sort of new age-y way that oriental peoples are right-hemisphered and we are left-hemisphered -- that's another of these ridiculous and unhelpful dichotomies. But what one finds is that the far eastern peoples are much more able to use, in a balanced way, strategies of either hemisphere, which is how one would hope we would use our brain and minds. Whereas there's an enormously skewed distribution for the way in which westerners look at things, it's very much heavily skewed towards the way of looking at things with the left hemisphere.

Natasha Mitchell: I mean you saw the romantic era as a great blossoming again of the right hemisphere, but the Industrial Revolution to the present day for you represents a major shift leftward in the brain, and of course we're not saying politically here, we're saying hemispherically in the brain.

Iain McGilchrist: Yes, that's right.

Natasha Mitchell: I mean just describe that shift for us to the present day.

Iain McGilchrist: I mean one of the striking things about the Industrial Revolution is that for the first time we were able to put into the outside world artefacts which conform very much to the way the left hemisphere sees the world -- simple solids that are regular, repeated, not individual in the way that things that are made by hand are. And to transform the environment it was a sudden and obvious move forward in our ability to control our environment and to project outwards onto it the world as conceived inwardly by the left hemisphere.

That's gone on into the 20th century but the interesting thing is that one might think of the Industrial Revolution and scientific materialism which emerged in the 19th century and is still with us at least in the biological sciences although I would say that physics has long moved on from that vision of the world to one that's closer to what both hemispheres see. But that movement is often seen as in opposition to modernist and postmodernist culture. I argue in the book that in fact that's not the case and that modernism and postmodernism are in fact also symptomatic of a shift towards the left hemisphere's conception of the world.

Natasha Mitchell: Which is interesting because I guess the postmodernist view would be that everything exists within a context and that perhaps there is no absolute truth and in a sense I would have thought that contextual framing of the world is more right hemisphere if your argument is to hold?

Iain McGilchrist: Well of course I agree that things are contextual and there's no absolute truth but unfortunately in postmodernism this often comes to mean there is no truth at all. There is nothing out there actually beyond the sort of paintings on the wall of the inside of our mind. And that seems to be very much more like what the left hemisphere sees, and in fact the products of the art of modernism and postmodernism bear striking resemblances to what the world looks like to people whose right hemisphere is not working very well.

That was something that was first pointed out indirectly by a marvellous book by Louis Sass, an American psychologist who wrote a book called Madness and Modernism in which he draws extensive parallels between the phenomena of modernism and postmodernism and of schizophrenia. Deficits of the right hemisphere present a world in which the literal triumphs over the metaphorical, things taken out of context triumph over their meaning in a context, particularly a social context, and the sense of connectedness to others -- empathy and so forth is lacking and the world appears to be a heap of fragments and one can see that in the sometimes wonderful but bizarre and exotic artistic productions of people with schizophrenia.

Natasha Mitchell: You, Iain, do lament the loss of our relationship to beauty, to body, to spirit and art. Is that to blame on the left hemisphere as well?

Iain McGilchrist: Well again because its approach is largely reductionist, I think yes, it doesn't really have the capacity to understand what it's not able to see. There's a rather nice article by Stanley Fish called 'Does Reason Know what Reason Doesn't Know' which I think is a good point. The problem really in essence is that the left hemisphere is not aware of what it is not aware of in that sort of like Rumsfeld-like formula but you know that's what gives it a sort of confidence which one can anthropomorphise as sort of an arrogant stunt. And that's the difficulty that we face, is getting a hearing at all for what the right hemisphere has to say.

Natasha Mitchell: But clearly you're at risk of further dichotomising between left and right hemispheres in the brain in the way that all the sort of popular mythologies about the hemispheres would have us believe. Clearly beauty, the body, the spirit, art, emotion aren't purely the domains of the right hemisphere?

Iain McGilchrist: They certainly aren't and both are contributed to by both hemispheres absolutely. But at the moment what I think is that a rather reductionist version of what they might be is evident not just in science but in our popular culture and indeed is expressed in the kind of art that is created nowadays too. So I think a lot of the power of art to alert us to things beyond ourselves, yes, what is known as the transcendent I think that has been lost. There's a sort of ironising undercutting of the power of beauty, the power of art, the power of the spirit; don't want to sound evangelical here, but these things are important and need to be mentioned. You know a lot of very great scientists have always said that these things are an important part of what science acknowledges and pays tribute to. So, you know, I'm hopeful that the synthesis that I consider would be fruitful can be re-established. At the moment things seem to be very skewed.

Natasha Mitchell: Well Iain McGilchrist, it's a grand, provocative, epic and enticing thesis and thank you for joining me on the program this week.

Iain McGilchrist: It's been a pleasure, thank you very much.

Natasha Mitchell: Iain McGilchrist, calling for a peace agreement, a reunion, in the hemispheric battleground of the brain. His vast book is called The Master and His Emissary: The Divided Brain and the Making of the Western World published by Yale University Press.