From The Philosopher, Volume LXXXXVIII No. 2


Plato’s Cave

and the 
Bicameral Brain
 

Jim Danaher




Throughout most of our Western history, and especially our modern history, during which 'mathematics and everything akin to mathematics' has exercised an hypnotic appeal against which we have had the most difficulty resisting. 

Modernity became obsessed with analysis and the elimination of vague, ambiguous, or contradictory ideas. We fell almost completely under its sway and came to imagine that the picture of reality that such thinking provided gave us the best way to understand our world and our place in it. 

It was as if we had finally found our way out of the cave and into the kind of light that Plato had thought existed with the Platonic forms. It appeared that modern thinkers had found their way out of the shadowy and mysterious realm of our actual experience and found the kind of certainty that Plato had sought.

Today, however, we are able to see that from a very different perspective because of what we know concerning the human brain. We now know that as appealing as such certainty is, it merely represents one way that the human brain is capable of thinking. Instead of the moving picture of our actual experience, we are capable of ideas that represent snap shots, which make the distances, perspectives, and relations that we actually experience appear fixed and give us the kind of clear and distinct ideas that we crave. 

Until recently, it was easy to fall under the sway of such analytic, abstract thinking and imagine it gave us the best way to truth and was therefore synonymous with reason itself. We now know, however, that such a mode of reason is merely one way we have of thinking about our world and ourselves. We now know that our desire for clear and distinct ideas, which began with Plato and culminated in the Cartesianism of Modernity, was merely one way we are able to think about the world, and although it gives us the kind of certainty that makes us feel divine, it does not give us a very realistic picture of our human experience.

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In the seventh book of the Republic, Plato sets forth his famous allegory of the cave. The traditional understanding interpreted it as Plato arguing that both becoming and being were real because there were two different worlds or realms of reality. One was the world of sense-data, which the Pre-Socratic philosopher, Heraclitus argued was purely a matter of becoming. In this world, nothing ever exists in a pure state of being but is always becoming something else. 

Plato however, claimed that there was another world where things did exist in a pure state of being. Parmenides and several other Pre-Socratic philosophers had long claimed that the world of which Heraclitus spoke was an illusory world produced by a naïve trust in our unreliable senses and that in fact reason showed us that only being truly existed and all becoming and change was illusory. Plato agreed with both Heraclitus and Parmenides: he believed that the world of our sense data was real and not merely illusory, but there was also a world of pure being - the parallel universe that Plato would come to describe as the world of the forms.

Since we have ideas of things that were eternal and unchanging, quintessentially geometirical andmathemematical concepts such as numbers or the idea of a circle as a figure with every point equal distance from the center, Plato believed that such entities must be more real than the temporal and mutable things we experience in the world of our senses. 

Everything that we call a circle in the world of our senses is never the real circle or a figure whose every point is perfectly equal distance from the center. It is only a mutable replica of that eternal and immutable idea of a circle. Plato further imagined that if there were things as perfect as asuch eternal and immutable ideas of things like a circle, perhaps there were also eternal, immutable, and perfect ideas of courage, justice, love, or virtue - the instances of which appear in this world of our senses as mere shadowy replicas.

But what kind of thing is this parallel univese? Plato set us on a course to overcome the ambiguous and vague ideas that arise out of our experience and discover clear and distinct ideas by which we might organize our understanding. He further imagined that since such clear and distinct ideas were very different from those that arise out of our experience in this world of sense-data, there must be another world that houses these immutable and eternal ideas upon which we desire to found our understanding. 

Although Plato spoke of another world that housed these eternal and immutable forms, and we equally have interpreted him in those terms for centuries, today we are open to a very different reading of Plato. That is because we now understand that what we naively attribute to the world outside of ourselves is often more a matter of how we think about the world than how the world actually is.

Since the time of Kant, philosophy has stressed that we bring much more to our experience of the world than we had previously thought. Furthermore, in the two centuries following Kant, we have come to discover that what we bring to our experience is much more than the innate mental hardware that Kant imagined. 

We now accept that we interpret our experience through linguistic concepts that are culturally and historically relative. Perhaps creatures without language, culture, or history perceive their experience as given, but human beings certainly should not.

Once we realize how relative our understanding is to our own culture, history, and language community, we become much more philosophical. Reality is no longer simply data that we experience but an interpretation that is open to reinterpretation given different cultural and historical concepts. As we gain ever-greater insight into our human condition, those insights provide interpretations not available to previous generations. One such insight concerns what we have recently come to understand about the nature of our bicameral brains.

Since at least the time of the Greeks, we have known that the human brain is composed of both a left and right hemisphere. Today, our advanced technology has brought us to a much better understanding of the two hemispheres and the way they function. With functional magnetic resonance imaging, neuroscientists think that they are able to see how the different parts of the brain respond to different types of stimulus and thus involve different types of thinking. One thing that they say they have found is that although the two hemispheres certainly work together, they alternate in dominance with different types of thinking. In a book on The Physiology of Behavior, Neil Carlson says:

In general the left hemisphere participates in the analysis of information . . . In contrast, the right hemisphere is specialized for synthesis; it is particularly good at putting isolated elements together to perceive things as wholes.
The consensus today is that we are naturally equipped with two very distinct abilities in terms of how to think about our experience. We can analyze our experience and break it down into ever-smaller parts, or we can join the parts of our experience together into ever-greater wholes. Both modes of thought are within our power and both have a logic, which governs their reasoning. To prefer one mode of thought to the exclusion of the other is to limit our rational capacity and leave us ‘half-witted’. 

Sadly, much of the Western intellectual tradition has done just that, focusing on the ‘analytic’ and neglecting the ‘holistic’. We have come to associate reason itself with left-brain analysis.

What is so attractive about left-brain analysis is that it divides our objects of thought into ever-smaller parts that eliminate all contradictions and leave us with clear and distinct ideas. For example, take any paradoxical or contradictory phenomena and begin to analyze it into its parts and the contradiction eventually disappears. Life as a whole, maybe both joyful and sorrowful, but we can analyze it into sorrowful parts and joyful parts thus eliminating the paradoxes and contradictions and leaving us with clear and distinct ideas. 

Both Plato and Aristotle certainly set us on that course, and in the interest of establishing such clear and distinct ideas, they introduced what we have come to know as the laws of thought. These laws of thought include the law of identity (A equals A), the law of non-contradiction (A does not equal not A), and the law of the excluded middle (either A or not A, but not both A and not A). Plato endorses the laws of non-contradiction and excluded middle in the Republic where he has Socrates say:

It is obvious that the same thing will never do or suffer opposites in the same respect in relation to the same thing and at the same time.
Likewise, in the Metaphysics, Aristotle says:
The same attribute cannot at the same time belong and not belong to the same subject and in the same respect. 
Both Plato and Aristotle understood that we naturally encountered contradictions but we could eliminate them by thinking analytically and dividing things up into ever-smaller parts until all the contradictions disappeared. Socrates is a contradiction in that he is both a father and not a father. We can eliminate that contradiction, however, by thinking about Socrates at one particular time or in relationship to one particular person. These are the qualifications that Plato and Aristotle ascribe above in order to analytically break things down into ever smaller parts and thereby eliminate contradictions and give us clear and distinct ideas.

In the modern era, Descartes took this a step further and convinced us that all clear and distinct ideas are true. This Cartesian thinking came to have such a hold on the modern mind that we eventually came to believe that only clear and distinct ideas were true. Consequently, analytic thinking came to be seen as synonymous with reason itself and ideas that were vague, ambiguous, or contradictory simply were not true.

Of course, there had always been an alternative, synthetic way of thinking that resisted the urge to analyze our experience into ever-smaller parts but instead leaves things whole and bears the contradictions and ambiguity that is so much apart of our actual experience. We can trace That tradition can be traced back to Heraclitus in the Greek world, and during the Christian period, the medieval mystics continued to practice such thinking in spite of the overwhelming influence of Plato and Aristotle. In the modern period, it found some expression with the Romantic Poets, but it was not until Hegel that it received a full philosophical explication and the status of logic.

Just as Plato and Aristotle had developed laws to govern analytic thinking, Hegel offered laws to govern synthetic thinking. With synthetic thinking, we deal with the whole rather than the parts, and when thinking about all the parts or respects together we certainly encounter contradictions, and the truth is often both/and, rather than either/or.

For Hegel, Plato and Aristotle’s laws of analytic thinking were artificial and made 'abstract identity its principle (Logic, 75).' When, according to traditional logic, we reason about whether Socrates was or was not a father, it is not Socrates we are reasoning about but one aspect of Socrates' life at one particular time. By abstracting one aspect of Socrates' life, at one particular time, toward one particular person, we create an abstract idea over which the traditional laws of thought rule. But when we think about things in their wholeness rather than as clear and distinct abstract ideas, however, 'everything is inherently contradictory', says Hegel in his Science, and the law of contradiction, rather than the law of non-contradiction is the guiding principle.

Hegel specifically attacked the law of identity, saying that, 'the law of identity says very little in itself '. The fact that A equals A is merely a tautology and has little meaning. It tells us almost nothing about the identity of a thing. The only way a thing truly takes on identity is through its otherness; that is, by including in its identity what it is not. Only a thing's otherness provides the boundaries that give it definition and meaning. Likewise Hegel also agreed with Heraclitus that since living things are always becoming, they must contain within themselves that which they are not.

It is one of the fundamental prejudices of logic as hitherto understood and of ordinary thinking, that contradiction is not so characteristically essential and immanent a determination as identity; . . . but contradiction is the root of all movement and vitality; it is only in so far as something has a contradiction within it that it moves, has an urge and activity.

A little later, he says something that is even more shocking to those who strictly adhere to the traditional laws of thought and imagine them to be universal and the basis of reason itself.
Something moves, not because at one moment it is here and at another there, but because at one and the same moment it is here and not here, because in this 'here', it at once is and is not. 

This is an obvious contradiction, and the laws of thought would say that something could not be here and not here at the same time, but that is only true if we think of time analytically whereby time moves from one fixed, analyzable point to another (for example, t1, t2, t3…), thus constituting a series of present moments. If that is the nature of time, then Hegel is certainly wrong, since something is here, for example, at the present moment (for example, t4) and not anywhere else. If, however, there are no fixed points on the continuum that is time, and time, like motion, cannot be arrested without it becoming something other than time, then Hegel is right and something is both ‘here’ and ‘not here’ at the same time. To think of time as an ongoing continuum forces us to think contrary to the laws of non-contradiction and excluded middle. Like motion or time, living things, in their livingness, also defy arrest. 

Hegel also writes:

Abstract self-identity is not as yet a livingness.... 
Something is therefore alive only in so far as it contains contradictions within it. Yet, of course, we would not want to be without our ability to reason abstractly. Abstract analysis is certainly useful when constructing artifices like bridges and skyscrapers, or when we want to balance our checkbooks, but it is a grave mistake to believe that such thinking provides the best way to understand our human condition. The truth is that we are equipped with the ability to think analytically in order to get clear and distinct ideas, but we are also able to resist that temptation and bear the vagueness and ambiguity that so naturally comes with our human experience. 

The challenge is to resist the impulse to believe that one way of thinking is superior to the other. As Leo Straus says in What is Political Philosophy, human beings:

… are constantly attracted and deluded by two opposite charms: the charm of competence which is engendered by mathematics and everything akin to mathematics, and the charm of humble awe, which is engendered by meditation on the human soul and its experiences. Philosophy is characterized by a gentle, if firm, refusal to succumb to either charm.
What Plato expressed so long ago with his allegory of the cave was not, as he imagined, about another world, but rather about the way we desire to think about our human experience. Not only do we desire to know the forms so we might organize our understanding correctly, but we want them to be the kind of clear and distinct ideas we find in geometry. 

In the modern period, Descartes convinced us that such a Platonic ambition was the way to solve all of our problems and consequently the modern mind came to associate the analytic thinking of the left-brain as synonymous with reason itself. 

Consequently, no contradictory, ambiguous, or vague ideas could claim to be true. With such thinking, there were no mysteries, only puzzles that in time we would solve through a single mode of right thinking. Modern science told us that they had discovered a singular right way of thinking that if followed would eventually bring us to a complete understanding of the world and our place within it.

What we now understand much better than both Plato and Descartes is that we are hard-wired to reason in two very different and distinct ways: we can think analytically in order to get clear and distinct ideas and thereby eliminate all ambiguity and vagueness, or we can leave our experience whole and bear the paradoxes and contradictions that are so much a part of that actual experience. Plato might have imagined these as two different worlds but we now have the benefit of another way to interpret them - not as two universes that never interact but two distinct ways to think about the same world.

Furthermore, since the human brain provides us with two very distinct ways of interpreting our experience, there should not be a question of which is superior to the other. Both are part of our natural capacity and we should not have to choose one to the exclusion of the other. The trick is to have a whole mind that is capable of both modes of reason; that is, that we can think analytically, do mathematics, and create computers and bridges, but we can also think in ways that bear the contradictions, vagueness, and ambiguity that is so much a part of our actual experience.


contact: Professor Jim Danaher, <philos1011@gmail.com
 

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