Dreams of Earth and Sky (29 page)
Read Dreams of Earth and Sky Online
Authors: Freeman Dyson
There are huge differences between Freud and Kahneman, as one would expect for thinkers separated by a century. The deepest difference is that Freud is literary while Kahneman is scientific. The great contribution of Kahneman was to make psychology an experimental
science, with experimental results that could be repeated and verified. Freud, in my view, made psychology a branch of literature, with stories and myths that appeal to the heart rather than to the mind. The central dogma of Freudian psychology was the Oedipus complex, a story borrowed from Greek mythology and enacted in the tragedies of Sophocles. Freud claimed that he had identified from his clinical practice the emotions children feel toward their parents that he called the Oedipus complex. His critics have rejected that claim. So Freud became to his admirers a prophet of spiritual and psychological wisdom, and to his detractors a quack doctor pretending to cure imaginary diseases. Kahneman took psychology in a diametrically opposite direction, not pretending to cure ailments but only trying to dispel illusions.
It is understandable that Kahneman has no use for Freud, but it is still regrettable. The insights of Kahneman and Freud are complementary rather than contradictory. Anyone who strives for a complete understanding of human nature has much to learn from both of them. The scope of Kahneman’s psychology is necessarily limited by his method, which is to study mental processes that can be observed and measured under rigorously controlled experimental conditions. Following this method, he revolutionized psychology. He discovered mental processes that can be described precisely and demonstrated reliably. He discarded the poetic fantasies of Freud.
But along with the poetic fantasies, he discarded much else that was valuable. Since strong emotions and obsessions cannot be experimentally controlled, Kahneman’s method did not allow him to study them. The part of the human personality that Kahneman’s method can handle is the nonviolent part, concerned with everyday decisions, artificial parlor games, and gambling for small stakes. The violent and passionate manifestations of human nature, concerned with matters of life and death and love and hate and pain and sex,
cannot be experimentally controlled and are beyond Kahneman’s reach. Violence and passion are the territory of Freud. Freud can penetrate deeper than Kahneman because literature digs deeper than science into human nature and human destiny.
William James is another great psychologist whose name is not mentioned in Kahneman’s book. James was a contemporary of Freud and published his classic work,
The Varieties of Religious Experience: A Study in Human Nature
, in 1902. Religion is another large area of human behavior that Kahneman chooses to ignore. Like the Oedipus complex, religion does not lend itself to experimental study. Instead of doing experiments, James listens to people describing their experiences. He studies the minds of his witnesses from the inside rather than from the outside. He finds the religious temperament divided into two types that he calls once-born and twice-born, anticipating Kahneman’s division of our minds into System 1 and System 2. Since James turns to literature rather than to science for his evidence, the two chief witnesses that he examines are Walt Whitman for the once-born and Leo Tolstoy for the twice-born.
Freud and James were artists and not scientists. It is normal for artists who achieve great acclaim during their lifetimes to go into eclipse and become unfashionable after their deaths. Fifty or a hundred years later, they may enjoy a revival of their reputations, and they may then be admitted to the ranks of permanent greatness. Admirers of Freud and James may hope that the time may come when they will stand together with Kahneman as three great explorers of the human psyche, Freud and James as explorers of our deeper emotions, Kahneman as the explorer of our more humdrum cognitive processes. But that time has not yet come. Meanwhile, we must be grateful to Kahneman for giving us in this book a joyful understanding of the practical side of our personalities.
Note added in 2014: Kahneman responded to the review in a letter to the editor:
Freeman Dyson’s generous review … greatly overstates my role in the story of scientific psychology. My discipline is indeed much more scientific than it was when William James and Sigmund Freud wrote their masterpieces, but the transformation was well underway long before I was born. The science of psychology grew in several stages in the twentieth century, from the schools of Gestalt psychology and behaviorism that I learned about as a graduate student around 1960, on to the cognitive revolution that was reshaping the intellectual landscape when Amos Tversky and I began our collaboration at the end of that decade, and from there to the developments in neuroscience and in the study of associative and emotional processes that attract many of the best graduate students of today.
Tversky and I were participants in the cognitive revolution, to which we initially contributed the idea that significant errors of intuitive judgment can arise from the mechanism of cognition, rather than from wishful thinking or other emotional distortions. We also had a glimmer of what later became the two-system idea. Our first joint paper, which documented mistakes in the statistical decisions of researchers, informally distinguished intuitive judgment from deliberate computation. The detailed study of contrasts between automatic and controlled processes began some years later in an Indiana laboratory, and many psychologists have refined and extended that distinction in the intervening decades. In my recent attempt to describe the interactions between fast intuitive thinking and
the deliberate self, I draw both on the work of these predecessors and on recent advances in the study of associative memory.
Scientists operate mostly in disciplinary silos, and it is rare for research in one field to influence work in other disciplines. My research with Tversky crossed some of these boundaries, in large part because of our use of demonstrations that were accessible to everyone: we engaged readers in simple problems in which they could observe errors in their own intuitions. Our work has therefore been more visible to outsiders than many other advances in psychological research, but it is best seen as a contribution to the thriving collective enterprise of modern experimental psychology.
This letter does not respond to my suggestion that psychology lives on both sides of the boundary between science and literature, combining the emotional insights of Freud and James with the experimental discoveries of Tversky and Kahneman. As I said in the review, the time for reconciliation has not yet come.
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Farrar, Straus and Giroux, 2011.
WHAT CAN YOU REALLY KNOW?
JIM HOLT
’
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Why Does the World Exist?: An Existential Detective Story
is a portrait gallery of leading modern philosophers.
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He visited each of them in turn, warning them in advance that he was coming to discuss with them a single question: Why is there something rather than nothing? He reports their reactions to this question, and embellishes their words with descriptions of their habits and personalities. Their answers give us vivid glimpses of the speakers but do not solve the riddle of existence.
The philosophers are more interesting than the philosophy. Most of them are eccentric characters who have risen to the top of their profession. They think their deep thoughts in places of unusual beauty such as Paris and Oxford. They are heirs to an ancient tradition of academic hierarchy, in which disciples sat at the feet of sages, and sages enlightened disciples with Delphic utterances. The universities of Paris and Oxford have maintained this tradition for eight hundred years. The great world religions have maintained it even longer. Universities and religions are the most durable of human institutions.
According to Holt, the two most influential philosophers of the twentieth century were Martin Heidegger and Ludwig Wittgenstein: Heidegger supreme in continental Europe, Wittgenstein in the English-speaking world. Heidegger was one of the founders of existentialism, a school of philosophy that was especially attractive to French intellectuals. Heidegger himself lost his credibility in 1933 when he accepted the position of rector of the University of Freiburg under the newly established Hitler government and became a member of the Nazi Party. Existentialism continued to flourish in France after it faded in Germany.
Wittgenstein, unlike Heidegger, did not establish an ism. He wrote very little, and everything that he wrote was simple and clear. The only book that he published during his lifetime was
Tractatus Logico-Philosophicus
, written in Vienna in 1918 and published in England with a long introduction by Bertrand Russell in 1922. It fills less than two hundred small pages, even though the original German and the English translation are printed side by side. I was lucky to be given a copy of the
Tractatus
as a prize when I was in high school. I read it through in one night, in an ecstasy of adolescent enthusiasm. Most of it is about mathematical logic. Only the last five pages deal with human problems. The text is divided into numbered sections, each consisting of one or two sentences. For example, section 6.521 says: “The solution of the problem of life is seen in the vanishing of this problem. Is not this the reason why men, to whom after long doubting the sense of life became clear, could not then say wherein this sense consisted?” The most famous sentence in the book is the final section 7: “Wherof one cannot speak, thereof one must be silent.”
I found the book enlightening and liberating. It said that philosophy is simple and has limited scope. Philosophy is concerned with logic and the correct use of language. All speculations outside this limited area are mysticism. Section 6.522 says: “There is indeed the
inexpressible. This shows itself. It is the mystical.” Since the mystical is inexpressible, there is nothing more to be said. Holt summarizes the difference between Heidegger and Wittgenstein in nine words: “Wittgenstein was brave and ascetic, Heidegger treacherous and vain.” These words apply equally to their characters as human beings and to their intellectual output.
Wittgenstein’s intellectual asceticism had a great influence on the philosophers of the English-speaking world. It narrowed the scope of philosophy by excluding ethics and aesthetics. At the same time, his personal asceticism enhanced his credibility. During World War II, he wanted to serve his adopted country in a practical way. Being too old for military service, he took a leave of absence from his academic position in Cambridge and served in a menial job, as a hospital orderly taking care of patients. When I arrived at Cambridge University in 1946, Wittgenstein had just returned from his six years of duty at the hospital. I held him in the highest respect and was delighted to find him living in a room above mine on the same staircase. I frequently met him walking up or down the stairs, but I was too shy to start a conversation. Several times I heard him muttering to himself: “I get stupider and stupider every day.”
Finally, toward the end of my time in Cambridge, I ventured to speak to him. I told him I had enjoyed reading the
Tractatus
, and I asked him whether he still held the same views that he had expressed twenty-eight years earlier. He remained silent for a long time and then said, “Which newspaper do you represent?” I told him I was a student and not a journalist, but he never answered my question.
Wittgenstein’s response to me was humiliating, and his response to female students who tried to attend his lectures was even worse. If a woman appeared in the audience, he would remain standing silent until she left the room. I decided that he was a charlatan using outrageous behavior to attract attention. I hated him for his rudeness.
Fifty years later, walking through a churchyard on the outskirts of Cambridge on a sunny morning in winter, I came by chance upon his tombstone, a massive block of stone lightly covered with fresh snow. On the stone was written a single word: WITTGENSTEIN. To my surprise, I found that the old hatred was gone, replaced by a deeper understanding. He was at peace, and I was at peace too, in the white silence. He was no longer an ill-tempered charlatan. He was a tortured soul, the last survivor of a family with a tragic history, living a lonely life among strangers, trying until the end to express the inexpressible.
The philosophers that Holt interviewed wander over a wide landscape. The main theme of their discussions is a disagreement between two groups that I call materialists and Platonists. Materialists imagine a world built out of atoms. Platonists imagine a world built out of ideas. This division into two categories is a gross simplification, lumping together people with a great variety of opinions. Like taxonomists who name species of plants and animals, observers of the philosophical scene may be splitters or lumpers. Splitters like to name many species; lumpers like to name few.
Holt is a splitter and I am a lumper. Philosophers are mostly splitters, dividing their ways of thinking into narrow specialties such as theism or deism or humanism or panpsychism or axiarchism. Examples of each of these isms are to be seen in Holt’s collection. I find it more convenient to lump them into two big groups: one obsessed with matter and the other obsessed with mind. Holt asks them to explain why the world exists. For the materialists, the question concerns the origin of space and time and particles and fields, and the relevant branch of science is physics. For the Platonists, the question concerns the origin of meaning and purpose and consciousness, and the relevant science is psychology.
The most impressive of the Platonists is John Leslie, who spent
most of his life teaching philosophy at the University of Guelph and is now living in retirement on the west coast of Canada. He calls himself an extreme axiarchist. The word “axiarchism” is Greek for “value rules,” meaning that the world is built out of ideas, and the Platonic idea of the Good gives value to everything that exists. Leslie takes seriously Plato’s image of the cave as a metaphor of human life. We live in a cave, seeing only shadows cast on the wall by light streaming in from the entrance. The real objects outside the cave are ideas, and all the things that we perceive inside are imperfect images of ideas. Evil exists because our images are distorted. The ultimate reality hidden from our view is Goodness. Goodness is a strong enough force to pull the universe into existence. Leslie understands that this explanation of existence is a poetic fantasy rather than a logical argument. Fantasy comes to the rescue when logic fails. The whole range of Plato’s thinking is embodied in his dialogues, which are dramatic reconstructions of the conversations of his master Socrates. They are based on imagination, not on logic.