THE SOUL OF REASON

The material presented here is taken from a working paper titled The Soul of Reason:  An Argument for a New Post-Modern Realism in Social Theory and Philosophy.  (D. H. Bowles 2020)

VI.  The Divided Brain Thesis

In 2009, a British psychiatrist named Iain McGilchrist published a book that has given new life to an old idea:  the nature and significance of the asymmetric hemispheric structure of the brain.   In this exhaustive study, titled The Master and His Emissary: the Divided Brain and the Making of the Western World, McGilchrist argues 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 recognisably human world; and that their difference is rooted in the bi-hemispheric structure of the brain.  It follows that the hemispheres need to cooperate, but I believe they are in fact involved in a sort of power struggle, and that this explains many aspects of contemporary Western culture.

McGilchrist’s arguments are not universally accepted among brain scientists, but neither are they universally rejected.  In fact, his thesis has received considerable attention and support both within the scientific community, and in the public domain.  McGilchrist’s divided brain thesis actually consists of two related but distinct claims:  1) that the hemispheric asymmetry of the brain provides the basis for two radically different modes of experience in human consciousness, and 2) that these two distinct modes of experience are highly significant for the trajectory of human history and culture.  That is, while these two distinct modes of experience are–in theory–compatible and complementary, they are also–in fact–competitive, and the competition between them has resulted in a dialectic movement in human history and culture between an emphasis on what might be called reason (on the one hand) and intuition (on the other) as the fundamental ground of human knowledge.  It would perhaps be fair to say that McGilchrist’s second claim is viewed somewhat more skeptically among social scientists than the first is among brain scientists.

One brain scientist whose view on this is of considerable interest to us here is a former neuroanatomist specializing in brain structure from the faculty of the Harvard Medical School named Jill Bolte Taylor.  In 1996, Jill Taylor suffered the rupture of an arteriovenous malformation (AVM) in the left hemisphere of her brain.  My Stroke of Insight (2006) is her own story of that experience, of the catastrophic loss of her left‐brain functions, her experience of her liberated right‐brain consciousness, and her eight‐year struggle back to what she considers full recovery, all informed by her neuroanatomical training in brain structure and function.  The story she tells includes vivid and detailed descriptions of the hemispheric asymmetries of brain function which operate, she says, “like parallel processors”:

To the right mind, no time exists other than the present moment . . . the moment of now is timeless, and abundant.  By its design, our right mind is spontaneous, carefree, and imaginative.  The present moment is a time when everything and everyone are connected together as one.  . . . our right mind perceives each of us as equal members of the human family.  It identifies our similarities and recognizes our relationship with this marvelous planet, which sustains our life.  It perceives the big picture, and how we all fit together to make up the whole.  Our ability to be empathetic, to walk in the shoes of another and feel their feelings, is a product of our right frontal cortex.

          In contrast, our left hemisphere is completely different in the way it processes information.  It takes each of those rich and complex moments created by the right hemisphere and strings them together in timely succession.  By organizing details in a linear and methodical configuration, our left brain manifests the concept of time, whereby our moments are divided into the past, present, and future. . . . Our left hemisphere language centers use words to describe, define, categorize, and communicate about everything.  Via our left hemisphere language centers, our mind speaks to us constantly, a phenomenon I refer to as ‘brain chatter.’  One of its jobs is to define our self, by saying ‘I am.’  . . . Without these cells performing their job, you would forget who you are, and lose track of your life and your identity. . . .

          Among other things, our left hemisphere categorizes information into hierarchies, including our likes and dislikes.  It places the judgement of ‘good’ on those things we like, and ‘bad’ on the things we dislike.  Through the action of critical judgement and analysis, our left brain constantly compares us with everyone else.  It keeps us abreast of where we stand on the financial scale, academic scale, generosity‐of‐spirit scale, and every other scale you can imagine.  Our ego mind revels in our individuality, honors our uniqueness, and strives for independence. (30‐33)

In later chapters, Taylor describes her own experience of the loss of her left‐brain function and the resulting experience of right‐brain consciousness, in terms such as these:

The harder I tried to concentrate, the more fleeting my ideas seemed to be.  Instead of finding answers and information, I met a growing sense of peace.  In place of that constant chatter that had attached me to the details of my life, I felt enfolded by a blanket of euphoria. . . . In this void of higher cognition and details pertaining to my normal life, my consciousness soared into an all‐knowingness, a ‘being at one’ with the universe . . . I could no longer clearly discern the physical boundaries of where I began and where I ended.  I sensed the composition of my body as being that of a fluid rather than that of a solid.  I no longer perceived myself as a whole object separate from everything.  Instead, I now blended in with the space and flow around me.  (41‐42)

          The now off‐line intellectual mind of my left hemisphere no longer inhibited my innate awareness that I was the miraculous power of life.  I knew I was different now, but never once did my right mind indicate that I was ‘less than’ what I had been before.  I was simply a being of light, radiating life into the world.  . .(70-71)

A number of comments are in order with regard to Jill Taylor’s testimony.  First, note the similarity between Taylor’s reference above to “chatter” generated by the left-brain language center, and then remember Wright’s description of his experience with the quieting of the default mode network through meditation as producing “a sense of liberation from the chattering mind.”  And then note the attribution of self-consciousness, self-identity and interest, perception of hierarchy, and comparative judgement all to left brain functionality.  And finally, observe how her descriptions of the experience of right-brain consciousness as transcendence of self and oneness with the universe all bear an unmistakable similarity to both descriptions of mystical experience, and reports of experiences obtained through the use of psychedelic drugs.

To sum it up, in Jill Taylor’s remarkable narrative, we are presented with:  1) a clear biological (i.e. ontological) basis for homo duplex (to use Haidt’s term) in the hemispheric structure and function of the brain, and 2) in the function of the right hemisphere, an equally clear biological (ontological) basis of the human capacity for transcendental (i.e., not-self) experience and, with it, a compelling case for a moral intuition of expansive (vs. parochial) community.

VII.  Psychedelic Drugs and the Experience of Altered States

Table of Contents

Conceptual Schematic of the Argument

Abstract

Download Working Paper (PDF)