Right-left brain hemispherics has, like MBTI and enneagram, worked its way into the popular psyche as a personality theory. Decades of research, however, have debunked many of the more popular myths that, for example, the left side is for math and science and the right for art and music. Both are involved in both activities.
In fact, the two hemispheres are involved in most mental activities, but, like the left and right hands, they play different roles, often countering and inhibiting the actions of the other. For example, while the left hemisphere is largely responsible for producing syntax for spoken and written language, the right gives it its meaning. While appreciating music is largely a right brain activity, the left brain is required for understanding music theory. Rote mathematics is a left brain activity but intuitive mathematics seems to take place on the right.
If one could give a theme to the right hemisphere it would be that it is responsible for seeing the gestalt or whole while the left sees the parts. Without the right, everything loses its meaning and becomes merely a collection of dead parts. Without the left, meaning becomes indistinct and thoughts are poorly articulated.
Another function of the left hemisphere is to create representations of reality. That is why it is used in spoken and written language, since these are abstract models of reality. The left hemisphere is concerned with what we know about the world not the world itself. The right hemisphere, although silent in language, is the opposite: concerned with the world as it is. We know from studying people with right-left separation, where the corpus callosum connecting the two halves is separated, that you use the right hemisphere to draw accurately to life while the left is only good for diagrams and near cubist drawings of three dimensional shapes as if seen from all angles at once. Normally, people can use either left or right hand to draw accurate shapes, but, with the callosum separated, only the left hand, as it is controlled by the right hemisphere, can draw true-to-life.
The right hemisphere not only presents external reality as it is, it also experiences internal reality as it is. Volition, social cognition, facial recognition, and values all appear to originate on the right while articulations of those experiences appear to come from the left.
This is the thesis presented in the heavily technical 2009 tome: The Master and his Emissary by psychiatrist Iain McGilchrist which released its 10 year anniversary edition in 2019.
Far from being a question about rational versus feeling, science vs. nature, McGilchrist argues that the right brain is the “master” to the left brain’s “servant”. The right brain’s job is to see everything as it is, perceive the big picture, and then allow the left brain to research or carry out the details and report back.
McGilchrist provides extensive detail in this 500 page book from literally thousands of individual pieces of research stretching back 200 years to support his thesis. Drawing on studies of people with left and right hemisphere damage, split brains, and modern imaging, he shows that while the difference between right and left is subtle, it is real and important. In particular McGilchrist argues compellingly that many of today’s problems stem from a role reversal between right and left, with the left imposing its mechanistic, diagrammatic, research assistant approach to reality upon reality itself. Like a leader who forgets the nation she serves, the left brain has forgotten her true master.
While one paper argues that McGilchrist’s neuroscience resembles the process and reality philosophy of the mathematician Whitehead, I have found that McGilchrist’s thesis has an uncanny resemblance to an earlier philosophy developed in the early 19th century encapsulated in the weighty book Will and Representation. Author Arthur Schopenhauer developed this philosophy, as he claims, by examining his own thoughts, and, given how neatly will and representation map to what we know about the right and left brains respectively, it is possible that he was intuitively aware of their distinct roles.
Schopenhauer defines Will as follows:
Will constitutes what is most immediate in [our] consciousness, but as such it has not wholly entered into the form of Representation … it makes itself known in an immediate way in which subject and object are not quite clearly distinguished
Meanwhile, McGilchrist says of the relationship between right and left hemisphere
[T]hinking is prior to language. What language contributes is to firm up certain particular ways of seeing the world and give fixity to them. This has its good side, and its bad. It aids consistency of reference over time and space. But it can also exert a restrictive force on what and how we think. It represents a more fixed version of the world: it shapes, rather than grounds, our thinking…
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.
The left hemisphere in its attempt to represent the world has to make truth decisions about what is right and wrong, true and false. It cannot handle the ambiguity that is so commonly found in our reality.
So 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.
Schopenhauer’s Will, while associated with volition and decision making, also includes the perceptual awareness of reality as itself before it is represented. This is not “mere perception” however but closer to what Heidegger called Dasein or the peculiarly human experience of being— the essential nature of things as we see them.
By perceiving reality as ambiguous, contradictory, through metaphor, art, music, and impressions, the right hemisphere presents to us what reality actually is. The left meanwhile presents reality as black and white with straight lines and hard edges.
Our Western civilization has been shaped by this attitude. The very shape of our cities with their sharp, abstract lines, road grids, signs and rules is a reflection of the world of the left hemisphere externalized. The natural world, by contrast, with its chaotic and contradictory behavior is much more in tune with the right hemisphere.
Both Will and the right hemispheric thinking are in line with the Buddhist notion of emptiness. The right hemisphere embodies general, unfocused awareness of reality as it is as well as inner silence. Through meditation one can escape the Representation of the left for a while and, by silencing the mind, experience reality as essentially as it possible for human beings.
It isn’t clear that volition itself is unique to either the right or left brain. Feelings that involve engaging with and approaching the world (anger for example) tend to take place on the left while those involves in retreating and withdrawing from it (disgust and sadness) tend to be on the right. Decision making, however, may be buried deep in the unconscious mind and may indeed have its seat on the right.
McGilchrist argues that neuroscience experiments that attempt to debunk free will by appealing to our conscious awareness of decision making (such as Libet’s hand motion experiment) are problematic. And they only debunk free will
if one imagines that, for me to decide something, I have to have willed it with the conscious part of my mind. Perhaps my unconscious is every bit as much ‘me.’
Thus, both Schopenhauer and Buddhist thought seem to intuitively grasp both the conflict between left and right and the primacy of the right over the left, both the conscious and unconscious minds. Neuroscience is proving that the brain is built that way both structurally and functionally.
Our civilization has been built on left brain representation and its tendency to want more and go faster. Probably nothing so exemplifies it than the present obsession with emptiness of space while the vibrant natural world we inhabit disintegrates around us. With global warming, climate change, and habitat destruction made worse by political polarization and paralysis compounded by the misery of grasping and getting for status, money, or beauty, and mental illness on the rise, the world desperately needs to embrace the fuzzy, many sided, retreating, big picture perception of right brained thinking. Art, music, spirituality, as well as the inter and intrapersonal skills are all at risk in a mechanized and increasingly empty world of plenty. The black and white thinking of the left that got us into this mess will not get us out no matter how appealing its certainty.