Book review: Touching a Nerve
Raymond Tallis finds Patricia Churchland’s neurophilosophy to be more neuro than philosophy
Touching a Nerve: The Self as Brain by Patricia Churchland (W. W. Norton & Co)
Patricia Churchland has been promoting the central thesis of her latest book – that we are our brains – for several decades and now she is tired of arguing. Instead, she accuses those who challenge this (eminently challengeable) dogma of being resistant to “knowledge that betokens a change in a whole way of thinking”. She compares them to the cardinals who refused to accept Galileo’s discovery of the moons of Jupiter and declined to look through his telescope, or the benighted souls who deny Darwinian evolution.
This ad hominem strategy is especially culpable in a book such as Touching a Nerve that appears to be for general readers who may be unaware that there are many pre-eminent philosophers (including Saul Kripke, Thomas Nagel and David Chalmers) and well-informed neuroscientists who do not subscribe to her belief that minds and brains are identical. They are not flat earthers; they believe that the theory is inadequate even to explain simple sensations such as pain, never mind the more complex modes of awareness that persons have.
In short, many of those who are unimpressed by the metaphysical claims of the neurophilosophers suffer not from an inability to set aside cherished beliefs in the soul, or a ghostly self, but from an allergy to bad arguments, elementary errors and unfounded claims. As one who researched in clinical neuroscience for the best part of 30 years, it has not escaped my notice that every aspect of our lives requires a brain in some kind of working order; but it does not follow from this that our lives consist in being that brain.
Nor does the observation that there is some correlation between brain activities and the levels and contents of consciousness demonstrate that brain activity is either the sole cause of, or is identical with, the levels and contents of consciousness.
Like many other neurosceptics, I agree that the brain is a necessary condition of consciousness, personality and so on, without feeling obliged to think that it is a sufficient condition of consciousness, personality etc. Of course, even wrong theories can be fruitful. So what does Churchland’s dogma bring to the party? What insights flow from it? She admits that we do not have anything close to a neural explanation for any of our ordinary functions, such as memory, how we solve problems, or even why we sleep and dream. But she is sure that something will turn up because, she tells us, she was afforded a realisation at the outset of her philosophical career that “mental processes are actually processes of the brain”. She has kept faith with her initial revelation.
Her confidence that advances in understanding human consciousness and tricky subjects such as ethics will come primarily from neuroscience is kept alive not by a steady flow of empirical data which somehow address metaphysical problems (itself somewhat unlikely) but by the way she talks about brains. “The mammalian brain” she says “is wired both for self-care and for care of others.” “Brains love predictability.” “[T]he brain makes fast and complex interpretations.”
By thus personifying the brain, she makes it easy for herself to get away with brainifying the person. And her personifications do not stop at whole brains. The insula – a small area of the cerebral cortex – is “a sophisticated how-am-I-doing area”. Even neurons in the motor cortex can make “a decision to turn the head in the direction of a sound”. If a neuron (a few thousandths of a millimetre in size) can make decisions, just imagine what nine billion can do.
If you think you are identical with the material goings-on in a material brain you may be inclined to conclude that free will is an illusion. Churchland, however, does not believe that her book was produced by events over which she had no control. There is a difference, she says, between brains with self-control and brains lacking self-control; indeed, there are brain mechanisms for self-control. Mechanisms do not seem to be the kind of entities that can confer free will. And exactly how the self, the control and its targeting are to be found within a buzz of neural activity is not clear, but she is confident that neurotransmitters such as adrenaline and dopamine may be key. Even so, she is not entirely sure what to do with the “my brain made me do it” plea, in part because her treatment of the philosophical problem of free will is perfunctory (to say the least).
Just how little neurophilosophy brings to the party is betrayed in the chapters dealing with morality, aggression and sex, where most of the insights she offers seem to originate from her inner Village Explainer, though she gives them an evolutionary gloss. There are frequent references to her early life and Lessons Learned Down on the Farm. From this we gain many home, not to say homely, truths. “Learning to exercise self-control is important not only concerning fears, but also concerning various temptations, impulses, emotions and seductive choices.” “Social life can be very subtle, often calling for wise judgement rather than strict adherence to rules.” “[D]eveloping good habits as early as possible is a sound if not infallible guide to living well.” As Gertrude Stein said of village explainers, they’re all right if you are a village but if you’re not, they’re not.
Significantly, her insights into human behaviour are not only banal but they seem to owe little to neuroscience. Admittedly, given that the brain deals largely in unconscious processes, we must try to develop (unconscious) habits that go with the grain of the brain, since, as she argues, “your values are what they are because your brain is what it is”. But then she remembers that “Our intuitions about what is right and wrong are strongly shaped by the prevailing conventions”. There’s the bit where you say it and the bit where you take it back.
Against the background of Churchland’s insistence that we are brain processes, the truism that “We live in a matrix of social practices, practices that shape our expectations, our beliefs, our emotions, and our behaviour – even our gut reactions” seems like a revelation. The yawn-worthy observation that “Our personalities and temperament are bent and formed within the scaffolding of social reality” is a refreshing acknowledgement of the extra-cranial realm within which we live and have our being.
Readers have to wait until the last chapter for a direct treatment of consciousness and the brain. Churchland gives a sketchy summary of some of what is known about the different neural activity that seems to be associated with being conscious of anything at all and being conscious of this and that. She does not say much about the conceptual problems of separating the level from the contents of consciousness – a proper job for a philosopher – but sticks to neuro-journalism. She devotes several pages to Bernard Baars’ “global workspace” theory of consciousness that tries to explain several of its most mysterious aspects: the way sensory signals from different sources are integrated; how sensory information is integrated with stored information; the limited capacity of consciousness; the need to be preferentially conscious of novel stimuli; and the ability to use information in planning, deciding and action. Unfortunately this theory, far from solving the problems, simply restates them, as the liberal sprinkling of personifying terms betrays.
Risibly, Churchland compares the elements that come together in the workspace with representatives of different departmental heads, bringing their wares to a progress meeting about a new MacBook under development, each armed with their own devices – a magnet plug, a solid state component etc. One of the most obvious inadequacies of this kind of “explanation” is that it does nothing to help us understand how the elements of consciousness come together, at a time, and over time, and yet still retain their distinct identity.
Churchland’s neurophilosophy is more neuro than philosophy. Touching a Nerve repeatedly slides away from the real philosophical problems of consciousness into aspects of neuroscience better expounded elsewhere. Ernest Gellner once observed that when priests lose their faith, they are unfrocked, but when philosophers lose theirs, they redefine their subject. Churchland’s redefinition of the philosophy of mind as neurophilosophy has brought little either to neuroscience or to our understanding of our conscious minds and even less to what it is to be a human being.