McGilchrist is a former psychiatrist, neuroimaging researcher, and professor of English at Oxford. He believes that the left and the right sides of the human brain, while exhibiting signs of plasticity, do have unique capabilities. The thesis of his book is that “for us as human beings there are two fundamentally opposed realities, two different modes of experience; that each is of ultimate importance in bringing about the recognizably human world; and that their difference is rooted in the bihemispheric structure of the brain. It follows that the hemispheres need to co-operate, but I believe they are in fact involved in a sort of power struggle, and that this explains many aspects of contemporary Western culture.” This thesis is at once simple and revolutionary. McGilchrist begins by pointing out some hard biology. “The corpus callosum contains an estimated 300-800 million fibres connecting topologically similar areas in each hemisphere. Yet only 2 per cent of cortical neurons are connected by this tract.” That is, most of our brain’s neurons are not connected by the only pathway that links our right and left hemispheres. Furthermore, when comparing various animals, the bigger the brain size, the less interconnected the hemispheres are.
McGilchrist points out that “lateralisation brings evolutionary advantages, particularly in carrying out dual-attention tasks…. The right hemisphere appears to be deeply involved in social functioning…. Where there is divided attention, and both hemispheres appear to be involved, it seems probable that the right hemisphere plays the primary role…. More specifically there is evidence of left-hemisphere dominance for local, narrowly focussed attention and right-hemisphere dominance for broad, global, and flexible attention…. What is new must first be present in the right hemisphere, before it can come into focus for the left…. Only the right hemisphere can direct attention to what comes to us from the edges of awareness…. The right hemisphere understands from indirect contextual clues, not only from explicit statement…. The right hemisphere takes whatever is said within its entire context. It is specialised in pragmatics, the art of contextual understanding of meaning, and in using metaphor. It is the right hemisphere which processes the non-literal aspects of language…. The left hemisphere is the hemisphere of abstraction, which, as the world itself tells us, is the process of wresting things from their context. This, and its related capacity to categorise things once they have been abstracted, are the foundations of its intellectual power…. The left hemisphere operates an abstract visual-form system, storing information that remains relatively invariant across specific instances, producing abstracted types or classes of things; whereas the right hemisphere is aware of and remembers what it is that distinguishes specific instances of a type, one from another…. The right temporal lobe deals preferentially with memory of a personal or emotionally charged nature, what is called episodic memory, where the left temporal lobe is more concerned with memory for facts that are ‘in the public domain’…. Not only does the right hemisphere have an affinity with whatever is living, but the left hemisphere has an equal affinity for what is mechanical. The left hemisphere’s principal concern is utility. It is interested in what it has made, and in the world as a resource to be used. It is therefore natural that it has a particular affinity for words and concepts for tools, man-made things, mechanisms and whatever is not alive…. Self-awareness, empathy, identification with others, and more generally inter-subjective processes, are largely dependent upon…. right hemisphere resources…. The right hemisphere plays an important role in what is known as ‘theory of mind’, a capacity to put oneself in another’s position and see what is going on in that person’s mind…. It is a capacity that children do not acquire fully until the age of four…. The right hemisphere is the locus of interpretation, not only of facial expression, but of prosody (vocal intonation) and gesture…. The left hemisphere reads emotions by interpreting the lower part of the face…. The right hemisphere alone seems to be capable of understanding the more subtle information that comes from the eyes…. It is the right hemisphere that understands the emotional or the humorous aspect of narrative…. It is the right hemisphere that mediates spontaneous facial expressions in reaction to humour or other emotions, including smiling and laughter. It is also the right hemisphere that is responsible for the peculiarly human ability to express sadness through tears…. The left hemisphere has a much more extensive vocabulary than the right, and more subtle and complex syntax. It extends vastly our power to map the world and to explore the complexities of the causal relationships between things…. The superiority of language stems from its nature as the hemisphere of representation, in which signs are substituted for experience…. The right hemisphere plays a vital part in language, too. It uses language not in order to manipulate ideas or things, but to understand what others mean…. It is therefore particularly important whenever non-literal meaning needs to be understood - practically everywhere, therefore, in human discourse, and particularly where irony, humour, indirection or sarcasm are involved…. The right hemisphere represents objects as having volume and depth in space, as they are experienced; the left hemisphere tends to represent the visual world schematically, abstractly, geometrically, with a lack of realistic detail, and even in one plane…. The left hemisphere exhibits a strong tendency to confabulate: it thinks it knows something, recognises something, which it doesn’t, a tendency that may be linked to its lack of ability to discriminate unique cases from the generalised categories into which it places them…. The left hemisphere needs certainty and needs to be right. The right hemisphere makes it possible to hold several ambiguous possibilities in suspension together without premature closure on one outcome. The right prefrontal cortex is essential for dealing with incomplete information and has a critical role to play in reasoning about incompletely specified situations…. The self as intrinsically, empathically inseparable from the world in which it stands in relation to others, and the continuous sense of self, are more dependent on the right hemisphere, whereas the objectified self, and the self as an expression of will, is generally more dependent on the left hemisphere…. The unconscious, while not identical with, is certainly more strongly associated with, the right hemisphere.” The right and left side might work in conjunction with each other, but there is a clear tension between the two hemispheres in each human brain.
After sketching the basic functions, McGilchrist continues by exploring how each hemisphere interacts with language, music, and truth. He suggests that music has ancient origins, even predating language. In prehistoric society, music played an integral role in religion, ritual, celebration, and in uniting the community. It was not passively experienced, but as shared-performance, binded the people in a single experience. Poetry also evolved before prose. “Most forms of imagination, for example, or of innovation, intuitive problem solving, spiritual thinking or artistic creativity require us to transcend language.” Words influence our perceptions, but thinking evolved prior to language. “What language contributes is to firm up certain particular ways of seeing the world and give fixity to them…. Language may not, after all, have originated in a drive to communicate - that came later - but as a means of mapping the world…. It is a means of manipulating the world…. Language enables the left hemisphere to represent the world ‘off-line’, a conceptual version, distinct from the world of experience, and shielded from the immediate environment, with its insistent impressions, feelings, and demands, abstracted from the body, no longer dealing with what is concrete, specific, individual, unrepeatable, and constantly changing, but with a disembodied representation of the world, abstracted, central, not particularised in time and place, generally applicable, clear and fixed. Isolating things artificially from their context brings the advantage of enabling us to focus intently on a particular aspect of reality and how it can be modeled, so that it can be grasped and controlled.” The right hemisphere plays with metaphor. “Everything has to be expressed in terms of something else, and those something elses eventually have to come back to the body…. Metaphor embodies thought and places it in a living context…. Language originates as an embodied expression of emotion.”
McGilchrist begins to show how the functions of each hemisphere have consequences for how humans interact with the outside world. “Attention is a moral act: it creates, brings aspects of things into being, but in doing so makes others recede.” He posits that philosophy in the Western tradition is a left hemisphere process. “It is verbal and analytic, requiring abstracted, decontextualised, disembodied thinking, dealing in categories, concerning itself with the nature of the general rather than the particular, and adopting a sequential, linear approach to truth…. [After all,] manipulation and use require clarity and fixity, and clarity and fixity require separation and division…. According to the left hemisphere, understanding is built up from the parts; one starts from one certainty, places another next to it, and advances…. It conceives that there is objective evidence of truth for a part outside the context of the whole it goes to constitute. According to the right hemisphere, understanding is derived from the whole, since it is only in light of the whole that one can truly understand the nature of the parts…. The left hemisphere is always engaged in a purpose: it always has an end in view, and downgrades whatever has no instrumental purpose in sight. The right hemisphere, by contrast, has no designs on anything. It is vigilant for whatever is, without preconceptions, without predefined purpose…. The right hemisphere is the primary mediator of experience, from which the conceptualised, re-presented world of the left hemisphere derives, and on which it depends…. The left hemisphere does not itself have life…. The means of argument - the three Ls, language, logic and linearity - are all ultimately under left-hemisphere control…. Its point of view is always easily defensible, because analytic…. The left hemisphere builds systems, where the right does not. It therefore allows elaboration of its own working over time into systemic thought which gives it permanence and solidity…. The existence of a system of thought dependent on language automatically devalues whatever cannot be expressed in language…. The left hemisphere is not keen on taking responsibility. If the defect might reflect on the self, it does not accept it. But if something or someone else can be made to take responsibility - if it is a ‘victim’ of someone else’s wrongdoing, in other words - it is prepared to do so.” Imitation is the function of the right hemisphere. Only humans imitate means as well as ends when trying to achieve a goal. Imitation is at root escaping one’s own experience to enter the mind of another. “More empathic people mimic the facial expressions of those they are with more than others…. The process of mimesis is one of intention, aspiration, attraction and empathy, drawing heavily on the right hemisphere, whereas copying is the following of disembodied procedures and algorithms, and is left-hemisphere-based.”
Through the rest of his book McGilchrist posits that, in the Western world, there has been a historical battle between the two hemispheres that has ebbed and flowed through the ages. At first, the right hemisphere was ascendent. “In the Homeric era, the sense of self is intimately bound up with ‘interpersonal and communal dialogue’ in a shared ethical life…. The hiddenness or necessarily implicit quality of Nature requires a particularly alert flexibility on the part of those who go to approach her. ‘Hidden structure is superior to manifest structure’; and openness is required by the seeker of wisdom.” Heraclitus’ philosophy did not turn inward, but sought to carefully study the phenomenal world. “Opposites define one another and bring one another into existence.” However, soon after, the left hemisphere would gain sway. Plato’s “legacy includes the (left-hemisphere-congruent) beliefs that truth is in principle knowable, that it is knowable through reason alone, and that all truths are consistent with one another…. Plato’s belief that knowledge must be unfailing and general led to the position that we cannot know things that are changing or particular.” The ideal forms were all that were worth knowing and striving towards. Ideas about things were prized over the things themselves. Plato particularly disdained poetry, putting in Socrates’ mouth, “all the poets from Homer downwards have no grasp of reality but merely give us superficial representation.” Hans Peter L’Orange writes that this trend away from nuance continued in the traditions of the Roman Empire where “there is a movement away from the complex towards the simple, from the mobile towards the static, from the dialectic and relative towards the dogmatic and the authoritarian, from the empirical towards theology and theosophy.” McGilchrist posits this trend furthered with the early Christians, whose “passion is for control, for fixity, for certainty; and that comes not with religion alone, but with a certain cast of mind, the cast of the left hemisphere.”
McGilchrist suggests that in the Renaissance priority begins to shift back to the right hemisphere. Giotto, in the late thirteenth and early fourteenth centuries, is the first painter to employ perspective. “Perspective mediates a view of the world from an individual standpoint.” The Renaissance ushered in an age of more cultural tolerance and plurality. Melancholy was co-mingled with wit and intelligence. Sadness and pleasure were intertwined. This growth in nuance was, to a large degree, countered by Luther’s Protestant Reformation. “The outer world was in itself empty, and therefore the only authenticity lay in the inner world alone…. The Reformation is the first great expression of the search for certainty in modern times.” The literal Word replaced metaphors in the quest for human understanding. This need for certainty continued with the Enlightenment, which replaced Luther’s religion with a secular science of positivism. Rationality imposes an either/or mentality on life. “Whereas reason respects the implicit, the ambiguous, the unresolved, rationality demands the explicit, the clear and the complete.” This trend was in opposition with artistic creation and this tension grew into the Romantic movement. “Art is by its nature implicit and ambiguous. It is also embodied: it produces embodied creations which speak to us through the senses, even if their medium is language, and which have effects on us physically as embodied beings in the lived world.” Max Scheler stated, “For this reason poets, and all makers of language having the ‘god-given power to tell of what they suffer’ [Goethe, Marienbader Elegie], fulfill a far higher function than that of giving noble and beautiful expression to their experiences and thereby making them recognizable to the reader, by reference to his own past experience of this kind. For by creating new forms of expression, the poets soar above the prevailing network of ideas in which our experience is confined, as it were, by ordinary language; they enable the rest of us to see, for the first time, in our own experience, something which may answer to these new and richer forms of expression, and by doing so they actually extend the scope of our possible self-awareness. They effect a real enlargement of the kingdom of the mind…. That indeed is the mission of all true art: not to reproduce what is already given (which would be superfluous), nor to create something in the pure play of subjective fancy (which can only be transitory and must necessarily be a matter of complete indifference to other people), but to press forward into the whole of the external world and the soul.” The Romantic movement was a move back towards the incompatible. Goethe emphasized, “we are, and ought to be, obscure to ourselves, turned outwards, and working upon the world which surrounds us.” McGilchrist suggests the Romantics returned to the theme of childhood again and again as “childhood represents innocence, not in some moral sense, but in the sense of offering what the phenomenologists thought of as the pre-conceptual immediacy of experience (the world before the left-hemisphere has deadened it to familiarity). It was this authentic ‘presencing’ of the world that Romantic poetry aimed to recapture.” Goethe stressed the impermanence of reality when he stated, “the phenomenon must never be thought of as finished or complete, but rather as evolving, growing, and in many ways as something yet to be determined.” Shelley suggested, “poetry lifts the veil from the hidden beauty of the world, and makes familiar objects be as if they were not familiar…. It creates anew the universe, after it has been annihilated in our minds by the recurrence of impressions blunted by reiteration.” The familiar is the realm of the left hemisphere, whereas the unique and particular of the right.
Industrialization, modernity, and post-modernity were each turns back towards the primacy of the left hemisphere. “The world is either robbed of its substantiality, its ‘otherness’, its ontological status as an entity having an independence from the perceiving subject; or alternatively seen as alien, devoid of human resonance or significance…. The more we rely on the left hemisphere alone, the more self-conscious we become; the intuitive, unconscious unspoken elements of experience are relatively discounted, and the interpreter begins to interpret - itself. The world it puts into words for us is the world that words themselves (the left hemisphere’s building blocks) have created…. [We become] modern man as homo consumens: concerned with things more than people, property more than life, capital more than work…. Socialism and capitalism are both essentially materialist, just different ways of approaching the lifeless world of matter and deciding how to share the spoils.” Modern man becomes passive to the world. “An admiration for what is powerful rather than beautiful, a sense of alienated objectivity rather than engagement or empathy, and an almost dogmatic trampling on all taboos, lies at the heart of the modernist enterprise.” There is novelty and shock, as opposed to newness- seeing afresh what one once thought of as familiar. The explicit reigns over implicit meanings. “Originality as an artist (as opposed to as a celebrity or a showman) can only exist within a tradition, not for the facile reason that it must have something by ‘contrast’ with which to be original, but because the roots of any work of art have to be intuitive, implicit, still coming out of the body and the imagination, not starting in (though they may perhaps later avail themselves of) individualistic cerebral striving…. Language makes the uncommon common. It can never create experience of something we do not know - only release something in us that is already there.” In modern society, knowledge has become professionalized. “Expertise, which is what actually makes an expert (Latin expertus, ‘one who is experienced’) would be replaced by ‘expert’ knowledge that would have in fact to be based on theory, and in general one would expect a tendency increasingly to replace the concrete with the theoretical or abstract.” Measurability and quantification become the standards of knowledge. Context could be neglected for general rules. Uniformity and equality become the overriding goals. In art, “metaphor and myth have been replaced by the symbolic, or worse, by a concept.” The world is seen as a collection of objects. However, “certainty is the greatest of all illusions: whatever kind of fundamentalism it may underwrite, that of religion or of science, it is what the ancients meant by hubris.”
