Altered Egos: How the Brain Creates the Self, 1st Edition

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Being and Brain

I cannot know as an object that which I must presuppose in order to know any object.

--Immanuel Kant, 1781

Descartes, Sherrington, and Sperry argued for the separation of body and mind. Their reasons for positing this separation were similar. These thinkers sought to explain how the unified mind, the “inner I” and the coherent self, was constructed from the diverse parts of the brain. In the final analysis, they concluded that the mind could not be reduced to the material brain. I have offered a solution to the problem of mental unification—namely, that the mind is a nested hierarchy of meaning and purpose created by the brain. The nested nature of the hierarchy of the “inner I” allows the self and the mind to be subjectively unified despite the diversity of the brain.

Does this proposal constitute the solution to the mind-body problem? Although I have tried to demonstrate why Descartes', Sherrington's, and Sperry's explanations for the separation of mind and brain were in error, there are real differences between the mind and brain, but not for the reasons proposed by these authors. In this chapter, I will argue that the reason the mind cannot be equated with the brain is the absolutely personal nature of meaning, purpose, and being. The mind is subjective and personal, and for this reason the mind and the self cannot be reduced to the brain.

The Subjective and Objective Points of View

Many scholars have made the argument that subjective and objective viewpoints on the brain are different in fundamental ways.¹ The philosopher Kant insisted that the perception of an object is presupposed by an experiencing self, and it therefore follows that the self can never be an object unto itself. The nineteenth-century philosopher Arthur Schopenhauer (1788–1860) was influenced by Kant's philosophy. Schopenhauer also insisted that no thing could be simultaneously subject and object. In Schopenhauer's words:

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Our knowledge, like our eye, only sees outwards, and not inwards, so that when the knower tries to turn itself inwards, in order to know itself, it looks into a total darkness, falls into a complete void. That the subject should become object for itself is the most monstrous contradiction ever thought of: for subject and object can only be thought one in relation to the other. This relation is their only mark, and when it is taken away the concept of subject and object is empty: if the subject is to become the object, it presupposes as object another subject—where is this to come from?²

The distinction between subject and object was emphasized again by the evolutionary psychologists George Henry Lewes (1817–1878) and Herbert Spencer (1820–1903):

When I am told that a nervous excitation is transformed into a sensation on reaching the brain, I ask, who knows this? On what evidence is the fact asserted? On examination it will appear that there is no evidence at all of such a transformation; all the evidence points to the very different fact that the neural process and the feeling are one and the same process viewed under different aspects. Viewed from the physical or objective side, it is a neural process; viewed from the psychological or subjective side, it is a sentient process.³

When the two modes of Being which we distinguish as Subject and Object, have been severally reduced to their lowest terms, any further comprehension must be an assimilation of these lowest terms to one another; and, as we have already seen, this is negatived by the very distinction of Subject and Object, which is itself the consciousness of a difference transcending all other differences. So far from helping us to think of them as of one kind, analysis serves but to render more manifest the impossibility of finding for them a common concept—a thought under which they can be united.⁴

The relationship between the subjective or inner mind and the objective reality of the material brain remains a puzzle to this day. In fact, this old problem has found a new life in the current debates among philosophers and neuroscientists on the nature of consciousness. Philosopher Thomas Nagel argued that the subjective nature of the mind could not be eliminated from discussions of the brain in his classic paper “What Is It Like to Be a Bat?”⁵ Nagel insisted on the subjective nature of mental phenomena and

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he argued against simple reductionism and physicalism because “every subjective phenomenon is essentially connected with a single point of view, and it seems inevitable that an objective, physical theory will abandon that point of view.”⁶ A central theme of Nagel's argument is that the subjective-objective dichotomy lies at the heart of the mind-body problem, and that “the subjectivity of consciousness is an irreducible feature of reality.”⁷

Other contemporary philosophers, including John Searle, have argued that the mind is phenomenally irreducible to the brain. Searle pointed out that successful reductions in science aim to remove any subjective element in the analysis. A feature of the world that “appears” a certain way in nonreduced form is ultimately reduced to its scientific “reality.” However, when we consider the mind, Searle argued that “we can't make that sort of appearance-reality distinction for consciousness because consciousness consists in the appearances themselves. Where appearance is concerned we cannot make the appearance-reality distinction because the appearance is the reality.”⁸ This led Searle to suggest that “the ontology of the mental is an irreducibly first-person ontology.”⁹

I agree with Searle that the mind cannot be reduced to the brain. In order to see why mind, and ultimately the self, cannot be reduced to the brain, and why the ontology of the mind and self is indeed an irreducibly first-person ontology, it is necessary to further explore the neurological origins and basis of meaning and purpose.

The Neurological Basis of Meaning

We first must understand what meaning and consciousness entail from the perspective of neurology. Lord Brain, one of the most influential neurologists of the twentieth-century, provided this beautiful example of how the brain creates meaning:

When my hand has been exposed to cold air, I say, “My hand is cold,” but when I grasp a stone I say, “This stone is cold.” In each case what I am experiencing is a cold sense datum, but in the one case I feel it in my hand and in the other case as belonging to an object. How do I perceive the size, shape and solidity of the stone? The touch and pressure sense-data which contact with the object evokes in my fingers are localized and distinguished as relating to different parts of the skin. Furthermore, my fingers themselves will be bent or straightened and separated to a greater or less extent; and each successive movement and posture of any finger arouses sense-data from the tendons and joints. If you move your fingers

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when your eyes are closed you are aware of these sense-data as originating in and referring to your fingers; but if you are holding an object in your hand these sense-data become fused with those just described and are felt as collectively conveying awareness of the size, shape and solidity of the object. Thus all the sense-data which are said to belong to an object when it is handled can in suitable conditions be experienced as belonging to the body.¹⁰

In neurology, we call the process of tactually identifying an object stereognosis. For a simple object such as a stone, recognition is almost immediate. But how does this happen? No single point of the body feels the entire stone; rather, the overall shape of the stone is extrapolated from the bending of the joints to accommodate it; its size by the distance between the fingers as they spread to cover as much surface of the stone as possible; its texture by the smoothness or roughness of the stone on the skin tips. If the task at hand is to identify the object, all these sensations that are actually occurring in the joints and skin are perceived as attributes of the object. The sensations within the hand are experienced within the “stone.” When the sensations of the body are referred to the stone, these sensations have created a meaning for the subject.

How did brains that create meaning come into being? To understand how meaningful brains evolved, it is helpful to first point out what nervous systems can accomplish without meaning or consciousness. Neural complexity, in and of itself, does not create meanings or consciousness. Some very primitive reflexes, such as the blink of the eye to a puff of air (known as the corneal reflex), a reflex that is present in any animal with a cornea to protect, involve highly complex neural states. But this reflex will occur even if the animal is asleep. Thus, pure reflexes do not necessarily entail conscious neural states.

Consider, for example, frogs, cats, and dogs whose spinal cords have been surgically separated from the brain. The hind limbs in these animals still will withdraw reflexively in response to certain stimuli, even though the spinal cord connected to that limb is disconnected from the animal's brain. Chemical irritants, tickling, or noxious mechanical irritation would normally invoke pain, itch, or other sensations in the intact animal. But since the involved segments of the spinal cord that receive these stimuli are disconnected from the brain (specifically the part of the brain called the thalamus necessary for conscious pain perception), the animal “feels nothing.” Sherrington pointed out that these reflexes occurred without mental accompaniment. Without the central connections to the brain,

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reflexes can occur and be accompanied by quite complex neural activity, but not by consciousness.¹¹

Another circumstance that demonstrates neural complexity in the absence of mind is the unfortunate patient who has had the spinal cord severed. If the spinal cord is severed completely, there is a physical separation of the nervous system above and below the lesion. Neural path-ways, which under normal circumstances convey pain impulses, can travel up the spinal cord only partway before being prevented by the cut through the spinal cord from reaching the parts of the brain where conscious sensation occurs. Under these circumstances, if one were to apply a painful stimulus to the foot, such as forcefully squeezing the toe, the foot might still withdraw—reflexively—yet the patient will report she “feels” nothing.

On the other hand, while some quite complex reflexes can occur without consciousness, some very simple organisms display behaviors that I would argue do involve meaning and consciousness. In the frog, a small, stationary stimulus situated directly in front of the animal evokes no response; it is for all intents and purposes invisible to the animal. But a small moving stimulus anywhere in the frog's visual field evokes an immediate dart of its tongue. Lettvin and coworkers recorded electrical activity from single fibers in the frog optic nerve during various stimulation procedures. They found one fiber population, called “net convexity detectors,” that responded when a small dark stimulus entered the receptive field, stopped, and moved about in a jerky fashion—just the kind of activity a mosquito might make if it were flying about in range of the frog's tongue. In fact, they found these fibers so exquisitely suited to detect a flying insect that they suggested they were best described as “bug perceivers.”¹²

For the bug perceivers of the frog brain to have “meaning” to the frog, the frog's brain has done something quite remarkable: it has created “an object” for the frog. Now you may say, “Dr. Feinberg, surely you're not suggesting that this frog is thinking to itself ‘Oh what a lovely fly . . .I think I'll eat it!’” No, not at all. But let us look at what is happening. The neural activity that creates the meaning “bug” is certainly within the frog's brain. But the frog reacts to that neural activity as though it were not occurring within itself. The frog reacts to that neural activity as if it were in the world signifying fly as something that occurs outside the frog's brain and being. The creation of outside objects is the fundamental starting point of all minds and the manner in which meaning is created.

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Sherrington called this projection of sensation on the body into the world projicience, and he had an explanation for its evolutionary origins. Sherrington reasoned that it was the development of the distance receptors (nose, ear, and eye), that enabled the registration of sensation from stimuli at a distance (smell, sound, and light). For an animal to register a stimulus that really is “out there in the world,” the animal had to be wired to react to the stimulus as if it were external and not on the body where the sensory stimulation really is occurring.¹³

Meaning, Qualia, and the Mind-Body Problem

Now here is the crux of the mind-body problem. The very point at which certain neural firings take on meaning for the frog is also the point at which the frog's point of view of its own brain and the observer's point of view of the frog's brain diverge. The frog's brain has now taken on a dual aspect: from the “outside” or external point of view, the point of view of the neuroscientist who studies the frog, the frog's neurons are palpable, material, tangible objects; but from the frog's “inner” point of view, those same neurons mean “bug.” It follows from this example of the frog's brain that meaningful neural states will always entail two irreducible perspectives: the “inside” subjective perspective and the “outside” objective perspective. The experience that the brain creates is meaningful only to one “I,” its possessor. In this way, meaning and consciousness are irreducibly personal. When a neurological event carries meaning, the subjective aspects of the experience cannot be reduced to the objective neurological events.

Consider again the patient with the spinal cord injury. Suppose I, the neurologist, also acquired the same spinal injury, such that I, like my patient, had no sensation from the waist down. It would make little difference, from the standpoint of my consciousness, if I squeezed my patient's toe or my own. In either circumstance the withdrawal of the toe could occur but neither of us would “feel” anything. If there is no “first person” or “I” associated with the response, there is no mind or subjective meaning involved with the reflex. With the subjective aspect of the response entirely removed, the withdrawal of the foot occurred without a subject. If I as the neurologist wish to analyze in this circumstance the reflex, I have no problem reducing the entire reflex to the neurons that created it. I can reduce the entire neurological event, beginning to end, to the firing of the neurons involved in the spinal reflex without recourse to a “mind” or self or an inner “I.” However, if either of us feels the toe as it is squeezed, if there is an “inner I” that has an experience that means

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“pain,” we do have a problem reducing the neurological event to the brain. Once an event is meaningful, as was the case with the frog and the fly, the observer's point of view and the subject's point of view diverge.

We are now confronted with the difficult issue of qualia, or the “raw feels” of experience. Qualia are the feelings and sensations attached to experience. They are the sensations of “what it is like to be” in a certain brain state. Thus, tastes, smells, sounds, pains are qualia. Some philosophers, like Daniel Dennett, have denied that qualia exist;¹⁴ others, like the philosopher Joseph Levine, claim that there is an unbridgeable gap between qualia and the brain.¹⁵

The problem of qualia, and the seemingly unbridgeable gap between observing a brain in a feeling state and being a brain that it is in a feeling state, is highlighted by the use of a fictional device that the philosopher Feigl called an“autocerebroscope.”¹⁶ Actually, no one to my knowledge has ever built an autocerebroscope, but nothing in theory would prevent the construction of a fully functional prototype. The autocerebroscope is a contraption that attaches to your head with a probe that goes through your skull. There is a viewer attached to the probe with a magnification device that allows you to observe the neurons of your own brain. Suppose one day, as you are merrily viewing your brain, you come upon your thalamus, the source of your feeling of pain. Suddenly you sneeze, and the scope's eyepiece pokes you in the eye! You now experience intense pain while you are looking through the scope at the very neurons in the thalamus that created that pain.

Now you ask yourself: Did you see anything through your autocerebroscope that was equal to the pain that you experienced? Was there anything that you observed that explained your pain? You surely saw the neurons responsible for your pain, and you could analyze the brain chemistry of these neurons, but does this allow you to reduce your pain to those neurons? It was your neurons themselves, not your image of the neurons through the viewer, that hurts! It occurs to you that there appears to be a gap between the neurons as they are observed by you and the neurons themselves as they are experienced by you within your brain. And you cannot find the source of this difference no matter how long and hard you observe your brain and think about the thalamus.

The problem of qualia and the uncertain ontological status of how things feel is also due to the irreducibility of the inside and outside perspectives of the nervous system. Consider again squeezing the toe of a patient who has spinal cord damage. When the spinal cord is intact, it should be obvious that the quale of having one's toe squeezed—the pain involved in the experience—differs fundamentally depending on whether

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one has the experience of the pain oneself or observes it as a brain having the experience of pain. What is the importance of these differences for the neurologist? If one actually feels pain, one experiences the quale “pain.” When the neurologist observes the brain experiencing “pain” from the outside, she sees specific patterns of neural activity that can be accurately defined, but cannot see in the brain something neurological that is equivalent to the experience of “pain.” When viewed from the outside therefore, the quale “pain” really does not exist materially. From the outside point of view, my patient's qualia are illusory. Qualia are personal and the relationship between a givenbrain and a given mind differs whether one is the person having that brain and that experience.

Therefore, the idea that “being something,” like a bat, is necessary for an understanding of what it is like to be that thing, in my opinion, does not go far enough. Being in a state is necessary for its existence. It only exists relative to something being in that particular state. In order for there to be consciousness, there must be something being that consciousness.

This is why qualia, like meaning and purpose, have a fundamentally, irreducibly, first-person ontology. From the outside, we cannot ultimately reduce the experience of “pain” to the neural state that creates it because there is nothing material from the outside perspective to reduce. There is no materiality to the experience “pain” from the observer's point of view because the experience of pain from the inner point of view only exists as neural activity from the outside perspective.

This does not mean that qualia don't exist, or that the mind is “immaterial.” I do not aim to support any form of Cartesian dualism. To deny that feeling or qualia or consciousness exists is not only wrong, it avoids the question of what qualia really are. I only wish to point out that qualia, like meaning and purpose, only exist from the subjective point of view of the self. Consciousness is a “personal mosaic.” The neural states that carry meaning about objects in the world are uniquely “possessed”by the organism and are a nested part of that organism's totality. Qualia and being ultimately are not dissociable. Qualia and being are a unity. Teller puts this succinctly when he says “so-called qualia are not some separable feature of brain states which, logically, might or might not accompany them. Talk about qualia is just a confused way of talking about having an experience or of being in the state.”¹⁷ Qualia are meanings and meanings are personal. Our visions, our minds, our pains, are personal and have no material existence for anyone but ourselves. This is how neural states can mean something for the individual, can be that person's “mind,” but for the observer, that mind does not materially exist.

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The Brain Is Not About Itself

Now here comes the tricky part. What is it about the brain, what neurological factor or property allows the brain to create subjective neural activities? There is a simple fact about the brain that is often neglected that provides the answer to this question. The conscious brain has no sensation of itself. It has been known since the time of Aristotle that the brain is insensate.¹⁸ For instance, sticking a pin in the cortex itself evokes no pain that is referable to the brain itself. The brain has no sensory apparatus directed toward itself. As Globus puts it, the brain does not “represent in any way its own structure to the subject.”¹⁹ There is no way that the subject can become aware of his own neurons “from the inside.” They can be known only objectively from the “outside.” We have already seen that there is no “inner eye,” no inner homunculus watching the brain itself, perceiving its own neurons, no “brain-skin” which feels the neurosurgeon's knife. When I test a patients’ pinprick sensitivity by applying a pin to the hand, and I ask them to localize where on the body the sensation is, no one has ever pointed to their head. Conscious neural activity refers to things, not to the brain itself. Conscious neural states are about things, not about the neurons themselves (Figure 9-1).

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Just as meaning has a personal ontology, individual purpose also possesses a first-person ontology and exists only from the“inside” perspective of the self. From the observer's standpoint, we cannot locate in the brain an individual's purpose. The “will”is not something that can be touched or pointed to. One can identify the pattern of neural firing that creates volitional action within the brain, but there is nothing about the pattern of a particular neuron's firing that distinguishes its firing as part of a willful action per se. Just as meaning is embodied within the pattern of neural firing within the brain, individual purpose is embodied within the nested hierarchy of a person's actions. The ontology of purpose and action, like the ontology of meaning, is irreducibly personal.

Many philosophers have argued that one of the essential characteristics of the mind is the property of intentionality. The use of the word “intentionality” dates to medieval times. The term derives from the Latin verb intendo, which means to “point at” or“extend toward.” Intentional phenomena are said to be about or of or directed at something. For example, beliefs are considered intentional because they are about a state of affairs. A fear is considered an intentional state because it is a fear of something. Perceptual states are considered intentional because if I experience an object in the world, whether I see, hear, touch, or smell it, then I have a perception of an object. In a similar way, action states are considered intentional when they are directed at something in the world.²⁰

The seventeenth-century philosopher and psychologist Franz Brentano argued that intentionality is the defining feature of the mental, and only mental phenomena possess the characteristic of intentionality. Consider how Searle spoke about intentional states:

The second intractable feature of the mind is what philosophers and psychologists call “intentionality,” the feature by which our mental states are directed at, or about, or refer to, or are of objects and states of affairs in the world other than themselves.”²¹

From the philosophical perspective, intentional mental states are directed at or refer to something other than themselves. On the basis of neurological considerations, I have argued that the origin of meaning and minds—from frog to human—are based on the fact that the conscious brain does not refer to itself. The similarity between the neurological perspective and the philosophical point of view is striking.