“The Master and His Emissary” – The Fate of Iain McGilchrist’s Magnum Opus

by Dr Liam Kavanagh

Since its 2009 publication, many have been captivated by Iain McGilchrist’s The Master and His Emissary (TMAHE). The book, whose jacket is decorated by approving quotes from famous thinkers and neuroscientists, provides a compelling exploration of the curious division of the brain into two hemispheres. It also relates this hemispheric divide, which has fascinated and frustrated neuroscience for centuries, to a profound perspective on the nature of being and the evolution of western culture, all in erudite but still relatable language.

To offer the reader a preliminary, crass, and simplistic summarization of the book’s argument — the hemispheres create two worlds, and that of the right is holistic, embodied, living, and intuitive, while the left is more focused, linear, and analytical. McGilchrist is wary of such attempts at summary throughout, aware of the temptation for a nuanced account to slide towards crude dualistic hemispheric myths (right intellectual, left artistic.) He nevertheless demonstrates in painstaking detail over a few hundred pages that there is valuable substance to the idea of hemispheric duality. The book then diagnoses a widely suspected cultural illness in the West as resulting from its gradual alienation from the right hemisphere’s world. Highly compelling stuff, to say the least. Many readers seem to wonder why the book’s impact has not been still greater, given how well it seems to capture a pattern that those readers profoundly sense.

This review is a response to the above concerns. It is divided into self-standing sections with clear headings so that (hopefully) readers can find what they want. First, I review the main thesis of the book, and highlight aspects of the recent history of neuroscience and of the work itself that are important for understanding its reception. Second, to assess whether the book contradicted experimental evidence available at the time of its publication, I review its reception by qualified reviewers. Reviewers voiced notable praise and no damning objections on the basis of the neuroscience, and more guarded reactions to the historical arguments. Third, I address objections that I and likely many readers have heard repeated to the effect that any hemispheric specialization story conflicts with well-known facts about the brain. Fourth, I look at the nature of “viral ideas” and argue that TMAHE cannot by its nature be highly viral except within a particular, but nebulously defined, subset of the thought community. Fifth I discuss
structural factors within science that work against its wide acceptance. Sixth, I review the results of experiments and of reviews of related neural evidence that have emerged since the book’s publication. Finally I discuss the connections between mindfulness and the book’s thesis on hemispheric specialization, including existing evidentiary
connections and the difficulties and promise of establishing these.

You can download the full essay from our Institute page.