The Master and His Emissary

The Divided Brain and the Making of the Western World

By Iain McGilchrist
Yale University Press, 608 pages, 2009

Edited by Andy Ross

From the Introduction

This book tells a story about ourselves and the world, and about how we got to be where we are now. While much of it is about the structure of the human brain — the place where mind meets matter — ultimately it is an attempt to understand the structure of the world that the brain has in part created.

Whatever the relationship between consciousness and the brain — unless the brain plays no role in bringing the world as we experience it into being, a position that must have few adherents — its structure has to be significant. It might even give us clues to understanding the structure of the world it mediates, the world we know. So, to ask a very simple question, why is the brain so clearly and profoundly divided? Why, for that matter, are the two cerebral hemispheres asymmetrical? Do they really differ in any important sense? If so, in what way?

Iain McGilchrist is a psychiatrist and writer who works in London and lives on the Isle of Skye.

He believes that the mind and brain can be understood only by seeing them in the broadest possible context, that of the whole of our physical and spiritual existence, and of the wider human culture in which they arise.

After a scholarship to Winchester College, he was awarded a scholarship to New College, Oxford, where he read English. He graduated with a congratulatory first in 1975 and was awarded a Prize Fellowship at All Souls College, Oxford, where he taught English literature and read philosophy and psychology until 1982. He then trained in medicine and was elected to another All Souls fellowship in 1984. He made a career in psychiatry and was elected again to All Souls in 2002.


"A beautifully written, erudite, fascinating and adventurous book. It embraces a prodigious range of enquiry, from neurology to psychology, from philosophy to primatology, from myth to history to literature. It goes from the microstructure of the brain to great epochs of Western civilisation, confidently and readably. One turns its five hundred pages — a further hundred are dense with notes and references in tiny print — as if it were an adventure story ... McGilchrist tells us about the rapidly evolving technologies and experimental work in fascinating and lucid detail."
A. C. Grayling, Literary Review

"[McGilcrist] extends [the] received wisdom with a hugely ambitious, absorbing and questionable thesis: the two hemispheres have radically contrasting personalities; that they live in a state of creative tension, sometimes declining into open war; and that their struggle for supremacy provides the key to understanding the major cultural movements of human history."
Adam Zeman, Standpoint

"McGilchrist's careful analysis of how brains work is a veritable tour de force, gradually and skilfully revealed. I know of no better exposition of the current state of functional brain neuroscience."
W. F. Bynum, The Times Literary Supplement

"Like Jaynes, McGilchrist interprets human history as an unresolved quarrel between the left and right hemispheres. ... While Jaynes argued that the Greek gods were invented to explain the breakdown of the bicameral mind — our hemispheres were finally able to listen to each other — McGilchrist argues the opposite."
Jonah Lehrer, Bookforum

"[T]his remarkable survey of the human brain is one of few contemporary works deserving classic status."
Nicholas Shakespeare, The Times

"McGilchrist persuasively argues that our society is suffering from the consequences of an over-dominant left hemisphere losing touch with its natural regulative 'master' the right. Brilliant and disturbing."
Salley Vickers, The Observer

"A giant in his vital field shows convincingly that the degeneracy of the West springs from our failure to manage the binary division of our brains."
David Cox, Evening Standard

"[A] grand theory for our times. If properly understood and acted upon, it has the potential to transform our view of our selves and our cultures, and prevent us from making a huge number of mistakes that might otherwise seem like sensible decisions ... a truly wonderful book."
Jonathan Rowson, RSA blog

"A seminal book"
Ervin László, State University of New York

"McGilchrist, who is both an experienced psychiatrist and a shrewd philosopher, looks at the relation between our two brain-hemispheres in a new light, not just as an interesting neurological problem but as a crucial shaping factor in our culture ... clear, penetrating, lively, thorough and fascinating ... splendidly thought-provoking ... I couldn't put it down."
Mary Midgley, Newcastle University

"[A] masterpiece"
Todd Feinberg, Beth Israel Medical Center, New York

"[McGilchrist] is immensely erudite. He writes with great clarity, and while the book develops an argument it is also a treasure chest of fascinating detail and memorable quotation. Its thesis is profoundly interesting: most readers who enter here with time to spend will be richly rewarded ... the effort to make sense of the totality of our lives in terms of brain function is exhilarating and worthwhile."
Adam Zeman, Standpoint Magazine

"[A] genuine tour de force, a monumental achievement — I can think of no one else who could have conceived, let alone written, a book of such penetrating brilliance."
David Lorimer, Scientific and Medical Network Review

"One of the most exciting and thought-provoking books that I have read in a very long time, and beautifully written into the bargain."
Robin Briggs, Oxford University

"McGilchrist's demonstration of the damage which has been done, and is increasingly being done, by the dominance of the left hemisphere operating alone, is masterly and totally convincing."
Keith Sagar, University of Nottingham

"Novel, compelling, and profoundly consequential ... obviously the product of many years of research and thought on the part of a thinker of depth and originality as well as deep learning across a number of fields that are very seldom combined ... McGilchrist is an unusually good writer, with as much talent for clear and exciting exposition as anyone I can think of ... unbelievably rich ... the formulations are often beautifully done, managing to state in maximally clear fashion issues of the utmost subtlety. The erudition is staggering. The overall arguments are compelling and well-handled. I think the basic thesis is indeed of absolutely crucial cultural and intellectual importance."
Louis Sass, Rutgers University

"A brilliant, exciting and important book ... The conclusions seem to me extremely robust ... of extraordinary importance for both scientists and humanists. ... But in the end the value of the book is really in the rich and complex exploration of the two hemispheres and their cultural correlates."
John Onians, University of East Anglia

AR  I have to read this book immediately. It will rival and perhaps replace the intriguing classic
The Origin of Consciousness in the Breakdown of the Bicameral Mind by Julian Jaynes (1976)
in my personal treasury.

January 9, 2011

My Amazon review:

A long march on the left-right brain

The Master and His Emissary
by Iain McGilchrist

March 9, 2011


Iain McGilchrist has poured his life's work into the capacious frame of this book. Only a thinker who first spent some twenty years getting his case together could have produced so massively buttressed an argument for greater awareness of hemispheric differences between the two halves of our cerebral cortexes. The scientific need for a deeper and more nuanced understanding of our brains' lateralization is clear and acute, and the social pathologies consequent upon our ignoring this key feature of our anatomy are correspondingly important. That said, the investigations brought together in this book can only represent a small start on a huge task.

Dr. McGilchrist is certainly to be congratulated for having made a start. Previous work on this topic has been of variable quality, a fact which becomes alarmingly clear as McGilchrist reviews the panorama of that work. Such contrasts as intuitive versus logical, or emotional versus rational, or even male versus female, hardly do justice to the subtle and often tricky nuances of our hemispheric specialization. In future, any researcher who wishes to do justice to this topic will have to take due account of this fundamental book. In fact, any such researcher will have to start here, for it brackets all that went before.

At first I expected a monograph that in its scope and ambition would essentially update the classic work on the bicameral mind published in 1976 by Julian Jaynes, but Iain McGilchrist takes a rather different tack. Although the depth and the scope of his work invites comparison with Jaynes, who was thinking so far ahead of the empirical work of the time that parts of his classic work now seem almost nutty, McGilchrist has wisely held back from speculating on the evolution of consciousness. Given the cataract of works on consciousness that have appeared in recent decades, this is perhaps only prudent, but it also reflects the fact that hemispheric lateralization cannot really be expected to shed much light either on the physiological question of how the operation of neural networks sustains or creates phenomenal experience or on the psychological question of how the emergence of consciousness can be traced in the cultural evolution of Homo sapiens. However, McGilchrist does not shy away from conjecturally tracing any number of historic cultural impacts back to our differentially lateralized brains.

One reservation is worth emphasizing. This book is not a work of science in the modern data-driven sense. It is much more correctly considered as a work of philosophy in the sense that prevailed a century ago before the logicians took over. Iain McGilchrist is a writer who in comparison with William James or Sigmund Freud is more inclined to cite artistic works that have no scientific credibility in support even of his more scientific claims. For example, he expects his readers to accept that poetic thinkers like Wordsworth or Goethe had insights that we can translate reliably into harder modern terms. I doubt that this translation is possible without controversy, and hesitate to endorse the pursuit of science in such a manner. Gilchrist also writes in a dense and allusive manner that many scientists will find hard to take. The fact that readers of a more reflective disposition will enjoy the style is beside the point. The message of this book, if summarized too sharply, will sound to many scientists like a rant or a jeremiad against modern civilization and its evils. My five stars are intended to persuade such scientists to read the book anyway.