NONFICTION
Is It Possible to Explain How Consciousness
Works?
Credit...Evan
M. Cohen
By Jim Holt
Nov. 2,
2021
FEELING
& KNOWING
Making
Minds Conscious
By Antonio
Damasio
https://www.nytimes.com/2021/11/02/books/review/antonio-damasio-feeling-and-knowing.html
We all know
what it means to be conscious. Consciousness is what distinguishes being awake
from being in a coma or a state of dreamless sleep. I am now conscious, and so
(presumably) are you. Many animals — probably all mammals — have conscious
minds, but plants and bacteria do not. Nor do computers (so far). Nor do stars,
or rocks.
Why is
consciousness important? Well, in a way, it’s the basis of everything that’s
important. Without consciousness, there would be no pleasure or pain; no good
or evil; no experiences of beauty, or of love. In a universe that never evolved
conscious minds, nothing would matter.
Intimately
familiar though we are with it, consciousness confronts us with a mystery. It
doesn’t readily fit into our scientific conception of the world. Consciousness
seems to be caused by neural firings in our brains. But how can these objective
electrochemical events give rise to ineffable qualitative experiences, like the
smell of a rose, the stab of a pain or the transport of joy? Why, when a
physical system attains a certain degree of complexity, is it “like something”
to be that system?
This is the
“hard problem” of consciousness: the problem of how subjective mind arises from
brute matter. (There is also an “easy problem,” that of determining what role
consciousness plays in the information-processing economy of the mind. But one
thing at a time.)
In the last
few decades, the mystery of consciousness has exercised thinkers of all
stripes, sometimes driving them to rather desperate-sounding devices.
Philosophers (Thomas Nagel, David Chalmers) have flirted with “panpsychism,”
the idea that consciousness might be a fundamental ingredient of all matter,
right down to the atomic level. The Nobel-laureate physicist Roger Penrose has
speculated that some kind of quantum magic might be behind it. In his
mega-best-selling “Gödel, Escher, Bach,” the computer scientist Douglas
Hofstadter argued that consciousness arises when the brain becomes intricate
enough to form self-referential “strange loops” — neural equivalents of Gödel’s
notorious formula that says, “I am not provable.”
Meanwhile,
neuroscientists have tried to understand consciousness as a biological
phenomenon — like, say, digestion. Using brain-imaging and other empirical
techniques, they have sought out the neural signatures of conscious thought
within the gray spongy matter in our skulls. Among them have been the Nobel
laureates Francis Crick and Gerald Edelman, each of whom produced a book
outlining his own favored take on consciousness. Today, one of the most
distinguished researchers working along these lines is Antonio Damasio, a
Portuguese American who holds a chair in neuroscience at the University of
Southern California.
“Feeling
& Knowing” represents a distillation of themes Damasio has explored in
earlier books, which include “Descartes’ Error” (1994) and “Self Comes to Mind”
(2010). The most prominent of his preoccupations is the importance of feeling.
It is feeling, he thinks, that can bridge the conceptual abyss between the
physical body and the conscious mind.
Before
getting down to substance, a word about style. In a prologue, Damasio tells us
that readers of his earlier books often missed the key ideas amid all the
scientific details. So he set out to write “a focused and very brief book on
consciousness.” Brief the new book is: It consists of 40-odd sections, some
less than a page long, surrounded by ample white space. Each of these
mini-chapters reads rather like a prose poem — often soaring to lyrical
heights, though sometimes weighted down by bits of neuroscientific argot.
“Focused,” though, is not the mot juste for it: Despite its brevity, it can be
meandering and repetitious (“Feelings again, must we? We must indeed”). Crucial
ideas often lie enshrouded in an elegant mist of metaphor. Still, the quality
of the author’s mind, the boldness of his aims and the suspense of his argument
propelled me through the book.
Put with
brutal succinctness, Damasio’s brief goes like this: Mental activity consists
of a stream of “images” that map aspects of the world around us. But these
images, by themselves, cannot be conscious. For that, they must be related to a
perspective, an “owner,” a self — this, after all, is what subjectivity means.
And here is where feeling comes in. As Damasio uses the term, “feelings” are
“the hybrid, interactive processes of the interior, at once mental and
physical.” They register how well or badly its various subsystems are doing at
maintaining homeostasis, at keeping the organism alive and flourishing. So
feelings point within, to the interior; images point without, to the world. And
when feelings and images come together in the brain, the result is conscious
thought. To adapt a simile of Damasio’s, feelings are like a musical score
that, when added to the silent reel of images in the mind, produces cinematic
consciousness.
This is
Damasio’s solution to the mystery of consciousness. What’s not to like? Plenty!
First,
Damasio has adroitly dodged the “hard problem.” An image of (say) a bear is, in
his account, a pattern of neural firing in the brain. A feeling of (say) fear
is another such pattern. Put them together and you’ve just got a bigger and more
complicated pattern of neural firing. Why should it be accompanied by
qualitative consciousness? For Damasio to use the terms “images” and “feelings”
to refer to these electrochemical events is to make them sound already
conscious — which might be called the fallacy of tendentious nomenclature.
Second, for
Damasio consciousness requires possessing a sense of self, an ability to
entertain “me-ish” thoughts. But most mammals seem to have no such sense of
self. They are incapable of recognizing themselves in a mirror. This is also
true of human children in the first months of life — are we to suppose that
they are not conscious? This might be called the “Unfair to babies!” objection.
Third,
Damasio’s category of “feeling” is too capacious. It encompasses not only
emotions, but also desires, and states of pleasure and pain. Is all of this
really necessary for consciousness? Might not rational thought plus value-based
goals be enough? Call this the “Unfair to Mr. Spock!” objection.
I could go
on.
But if Damasio’s
account of consciousness is not an unqualified success, that merely puts him in
the company of all the other distinguished scientists and philosophers who have
tried to crack this conundrum. And happily, “Feeling & Knowing” has
supplementary virtues that make it well worth reading.
Chief among
these is how beautifully Damasio expatiates on the theme of feeling — on how
feelings “arise in the interior of organisms, in the depth of viscera and
fluids where the chemistry responsible for life in all its aspects reigns
supreme.” Here the master scientist unites with the silken prose-stylist to
produce one thrilling insight after another. For instance: The neural channels
that convey feeling, in contrast to those tasked with other mental functions,
are uninsulated from the cells that environ them, and from the blood itself.
This biochemical nakedness permits “intimate cross talk between body structures
and nervous system.” (D. H. Lawrence’s “thinking with the blood” is not, alas,
a pure metaphor.)
Damasio may
not have dispelled the mystery of consciousness in this book. But he has
succeeded brilliantly in narrowing the gap between body and mind.
Jim Holt is
the author of “Why Does the World Exist?”
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