The Story of Science and Ideas in the Twentieth Century
Joseph Henry Press, Washington 2002
|The book traces the history of ideas from
of certainty in the year 1900 through the advent of quantum uncertainty
and the replacement of nature's "building blocks" by notions of
In philosophy it examines the failure of Bertrand Russell's dream of
Atomism with the advent of Wittgenstein's Tractatus and his later
of language. It looks at the failure of Hilbert's program to place all
of mathematics on a strict logical basis and Godel's Incompleteness
The book also explores the end of representation in art, the rise of
and the false comfort given by such approaches as Risk Analysis.
It concludes that in an age in which the "expert" is increasingly fallible, responsibility now falls on individual citizens for the values, meanings and ethics of our society.
1. Quantum Uncertainty
2. On Incompleteness
3. From Object to Process
5. The End of Representation
6. From Clockwork to Chaos
7. Re-envisioning the Planet
8. Pausing the Cosmos
Que sais-je?" ("What do I know?" Montaigne)
The first year of a new century always appears auspicious. The year 1900 was no exception. Americans welcomed it in with the three Ps: Peace, Prosperity and Progress.It was the culmination of some outstanding achievements and looked forward, with great confidence, to a century of continued progress. It certainly looked as if the twentieth century would be an age of knowledge and certainty. Ironically it ended in uncertainty and ambiguity. This book is the story of that change and of a major transformation in human thinking. It argues what while our new millenium may no longer offer certainty it does hold a new potential for growth, change, discovery and creativity in all walks of life.
On April 27, 1900, Lord Kelvin, the eminent physicist and president of the Britain's Royal Society, addressed the Royal Institution, pointing out "the beauty and clearness of the dynamical theory". Finally Newton's physics had been extended to embrace all of physics, including both heat and light. In essence, everything that could be known was, in principle at least, already known. The president could look ahead to a new century with total conviction. Newton's theory of motion had been confirmed by generations of scientists and it explained everything from the orbits of the planets to the times of the tides, the fall of an apple and the path of a projectile. What's more, during the preceding decades James Clerk Maxwell had established a definitive theory of light that also incorporated Newton's theory. Taken together these two theories appeared to be capable of explaining every phenomenon in the entire physical universe.
The cusp of the twentieth century presents us with an irony. 1900 was a year of great stability and confidence. It saw the consolidation and summing up of many triumphs in science, technology, engineering, economics and diplomacy. As Senator Chauncey Depew of New York, put it in, "There is not a man here who does not feel 400 percent bigger in 1900 than he did in 1896, bigger intellectually, bigger hopefully, bigger patriotically," while the Rev Newell Dwight Hillis claimed, "Laws are becoming more just, rules more humane; music is becoming sweeter and books wiser." Yet, at that very moment other thinkers, inventors, scientists, artists and dreamers, including Max Planck, Henri Poincare, Thomas Edison, Gugliemo Marconi, Nikola Tesla, the Wright brothers, Bertrand Russell, Paul Cezanne, Pablo Picasso, Marcel Proust, Sigmund Freud, Henry Ford and Hermann Hollerith were conceiving of ideas and inventions that were to transform the entire globe.
1900 was the year in which flash photography was invented and speech was first transmitted by radio. Arthur Evans discovered evidence of a Minoan culture and the United States backed its paper currency with gold. Once the Gold Standard had been adopted, was there anything that could stand in the way of a greater degree of confidence in the future of their world?
1900 also represents the culmination of a period of rapid discovery. In the two previous years the Curies had discovered radium and J.J. Thompson the electron. Von Linde had liquefied air and Aspirin had been invented. Edison's Vitascope together with the magnetic recording of sound heralded the age of the movies.
Thanks to Nikola Tesla's inventions in alternating current, the city of Buffalo was receiving electrical power generated by Niagara Falls. Count von Zeppelin constructed an airship, the Paris Metro opened and London saw its first motor bus. Already the transmission of data by telephone and telegraph was well established by 1902 and the first faxed photographs were being transmitted.
1900 also saw a link between Britain's Trades Union Congress and the Independent Labour Party, a move that would eventually lead to the establishment of the welfare state. With such a dream of social improvement people could be excused for believing that the future would provide better housing, education and health services. Homelessness would be a thing of the past and, while those thrown out of work would need to tighten their belts a little, they would be supported by the welfare state and no longer face suffering and hardship.
Europe also experienced a great sense of stability in 1900. Queen Victoria, who had ruled since 1837, was still on the throne. She had become known as "the Grandmother of Europe" since her grandchildren were now part of the European monachy. Indeed all of the European kings and queens, as well as the Russian royal family, were a part of a single international family presided over by Victoria. It was for this reason, diplomats believed, there would never be a war within Europe.
On 18 May 1899, at the prompting Czar Nicholas II's Minister of Foreign Affairs, 26 nations met at The Hague for the world's first Peace Conference. There they established an International Court to arbitrate in disputes between nations. The Congerence outlawed poison gases, dumdum bullets and the discharge of bombs from balloons. Wars and international conflicts would be things of the past. The world itself was moving towards a new golden age in which science and technology would be put to the service of humanity and world peace
Yet when people look to a golden future they should not forget the role of hubris. Often our predictions return to haunt us. It is particularly ironic that in this same year, 1900, ideas and approaches began to surface that were to transform our world, our society and ourselves in radical and unpredictable ways. For while the twentieth century began with confidence and certainty it was to end in uncertainty and doubt.
What were those tiny seeds that were destined to blossom in such unexpected directions? In 1900 Max Planck published his first paper on the quantum and young Albert Einstein graduated from the Zurich Polytechnic Academy. A year later Werner Heisenberg was born. These two physicists would create the great revolutions of modern science. In 1900 Henri Poincare was working on an abstruse technical difficulty involving Newtonian mechanics. Over half a century later this would explode into chaos theory. Astronomers were looking forward to the opening of the great telescopes at Mount Wilson in 1904 and, in the decades that followed, Edwin Hubble would use these instruments to discover that the universe was far vaster than ever believed and, moreover, that it was continually expanding.
In 1900 biologists rediscovered the work of an obscure monk, Gregor Mendel. Ignored by the scientific community in the mid-nineteenth century, Mendel had examined the way physical characteristics are inherited when different varieties of garden peas are crossed. Who would have guessed that exactly a century after this rediscovery of the basis of genetic inheritance, the completion of the Human Genome Project would be announced?
This same year, 1900, saw the publication of Sigmund Freud's Interpretation of Dreams. Much more rational that a Victorian dream book that flirted with divination and the occult, it demonstrated that dreams are "the royal road to the unconscious" and, in turn, that our waking lives are ruled by the irrationality of the unconscious. The potential for violence and human irrationality was to be powerfully demonstrated again and again during the twentieth century.
At the end of the nineteenth century Percival Lowell used his fortune to establish his own observatory at Flagstaff, Arizona, with the aim of discovering life on Mars. In 1900 H.G. Wells, inspired by these ideas, published War of the Worlds with its image of the mass destruction of the human race. Ironically the real possibility of global destruction in the twentieth century did not arise from little green men from Mars but from human-made weapons of mass destruction.
1900 was the year when the young philosopher, Bertrand Russell, heard Guiseppe Peano speak at a conference in Paris. The lecture so inspired Russell that he devoted his life's work to the discovery of certainty in mathematics and philosophy. How this goal eventually subverted itself forms the core of Chapter 2.
In 1900, inspired by the writings of John Ruskin, Marcel Proust visited Venice. He abandoned the novel on which he had been working and, determined to seek some new way of expressing "man's" confrontation with eternity, he embarked on a master plan that was to terminate in one of the major literary works of the twentieth century. It was also the year that the 18-year-old James Joyce, after having had his first article published, decided to become a full-time writer. In this same year Picasso had his first exhibition and made a trip to Paris, an event that was to have a profound effect on art in the twentieth century. 1900 was also the year in which Paul Cezanne was working on his famous studies of Montagne Sainte-Victoire. The works he produced there had a revolutionary effect on painting and produced yet another form of doubt as he questioned the certainty of what he was seeing.
In the previous year Henry Ford had formed the Detroit Motor Company that would produce the famous Model T, a car that transformed American society. Add to this Ford's discovery of mass production through the assembly line and one understands in part why, when young Henry left his father's farm, only a quarter of Americans lived in a city, yet, when he died, well over half of them were city dwellers. In 1900 there were 8 thousand automobiles in the United States and 150 miles of paved road. Today the number of cars in the U.S. is close to one hundred million.
A few years earlier, in 1896, Herman Hollerith had created the Tabulating Machine Company to speed up the processing of data using a system of punched cards. In 1911 the company's name changed to International Business Machines. The radio vacuum tube had been invented (in 1904) and so both the physical components and the business infrastructure were already in place for the creation of the computer revolution.
In the same year as the creation of Hollerith's Tabulating Machine Company, Henri Becquerel discovered the radioactivity of uranium. A few decades later, while studying Becquerel's phenomenon, the German scientist Otto Hahn realized that the atom could be split. When knowledge of this process reached the United States, colleagues persuaded Einstein to write a letter to President Roosevelt recommending the building of an atomic bomb, out of the fear that Nazi scientists would do so first. And so was born the atomic age, and with it the possibility of the annihilation of all life one earth.
While the twentieth century began with certainty it ended in uncertainty. Never again will we have the same degree of pride in our knowledge. In our infatuation with science and technology we overestimated our ability to manipulate and control the world around us. We forgot the power of the mind's irrational impulses. We were too proud in our intellectual achievements, too confident in our abilities, too convinced that humans would stride across the world like gods.
Today we are wiser and more cautious. We are suspicious of great plans and global promises. We view with caution the sweeping proposals of experts and politicians. We savor unbounded optimism with a generous pinch of salt.
Above all we want a better world for ourselves, our children and our children's children. We have learned that ordinary people can have a voice. We will not put our lives blindly into the hands of politicians and institutions. We demand to be heard and we know we can be effective.
Now let us return in more detail to the twentieth century and discover the various ways in which certainty dissolved into uncertainty. Each chapter that follows tells us something about uncertainty in the worlds of art, science, economics, society, and environment. Each adds another layer to those increasingly complex questions: "Who am I?", "What do I know?" and "What does it mean to be human?"
In his talk Kelvin proposed his own solution to these "two clouds." As it turned out, he was totally wide of the mark. Ironically, what Kelvin had taken to be clouds on the horizon were in fact two bombshells about to create a massive explosion in twentieth century physics. Their names were relativity and quantum theory. Both theories had something to say about light.
Light, physicists like Kelvin argued, is a vibration, and like every other vibration it should be treated by Newton's laws of motion. But a vibration, physicists argued, has to be vibrating in something. And so physicists proposed that space is not empty but filled with a curious jelly called "the luminiferous ether." But this meant that the speed of light measured in laboratories on earth - the speed with which vibrations appear to travel through the ether - should depend on how fast and in what direction the earth is going through the ether. And, since the earth rotates around the sun this direction is always varying, as is the speed should vary over a year. Scientists therefore expected to detect a variation in the speed of light measured at various times in the year. However, very accurate experiments showed that this was not the case. No matter how the earth moves with respect to the background of distant stars, the speed of light remains the same.
This mystery of the speed of light and the existence, or non-existence, of the ether was only solved with Einstein's Special Theory of Relativity, which showed that the speed of light is a constant, independent of how fast you or the light source is traveling.
The other cloud on Kelvin's horizon, the way energy is shared by vibrating molecules, was related to yet another difficult problem - the radiation emitted from a hot body. In this case the solution demanded a revolution in thinking that was just as radical as relativity theory - the quantum theory.
If, through our acts of participation in nature, limits are placed on the extent of our knowing, then at least we should be able to find certainty in the abstract products of our own minds. Above all, shouldn't we be able to discover certainty within the world of mathematics? This is exactly what the philosopher Bertrand Russell believed as, in the year 1900, he listened to the Giusseppe Peano speak with great clarity about the foundations of mathematics and decided to devote himself to proving their absolute rigor..
The power and beauty of mathematics
Where we find certainty and truth in mathematics we also find beauty. Great mathematics is characterized by its aesthetics. Mathematicians delight in the elegance, economy of means, and logical inevitability of proof. It is as if the great mathematical truths just have to be that way and no other. This light of logic is also reflected back to us in the underlying structures of the physical world through the mathematics of theoretical physics.
In The Study of Mathematics , Bertrand Russell, put it this way: "mathematics takes us into the region of absolute necessity, to which not only the actual world, but every possible world, must conform." For the philosopher, "mathematics is an ideal world and an eternal edifice of truth. …in the contemplation of its serene beauty man can find refuge from the world full of evil and suffering."( Frederick Copleston paraphrasing Russell "The History of Philosophy Vol. VIII Bentham to Russell" Bantam, Doubleday Bell, NY, 1985) ) For the astronomer James Jeans(1877-1946), "God is a mathematician". And there is a saying amongst mathematicians that "God made the numbers. All the rest is made by humans."
Object to Process
Our bodies are formed of matter. We require matter, in the form of air, food and drink, in order to live. This material world is the one inalienable certainty of all life. In many of the world's religions it is symbolized by what has been called The World Tree, whose crown reaches up to heaven while its roots descend deeply towards the center of the earth. This tree is also an image of individual human life, a life that aspires to the transcendent, numinous, and spiritual by virtue of its secure foundation within the earth.
But our understanding of this stuff of the world was radically transformed by quantum theory. Chairs and tables dissolved into an empty space filled with colliding atoms. Then atoms broke apart into nuclei, nuclei into elementary particles and finally, elementary particles into symmetries, transformations, and processes in the quantum vacuum. Understanding this new reality required a change in thinking so deep that it reached down into the very language we speak. In place of nouns and concepts we must now dialogue in terms of verbs, process, and flux. Once again, this change in our approach to reality mirrors similar revolutions that have taken place in art, literature, philosophy, and social relations.
Since recorded history philosophers and religious teachers of all cultures have debated these questions. Some cultures have offered answers based on religion or mystical revelation. Others have created complex overarching systems of thought. Some philosophers answer these questions with yet other questions. Others seek closure and completeness and wish to create a single philosophic approach that will encompass all questions and all answers.
Some religious and philosophical systems deal in poetic images as they seek to express the transcendent. Others, particularly in the West, espouse the goals of clarity and directness. On the other hand some philosophical writings become dense and convoluted as philosophers attempt to express the ineffable in words and force language into tasks for which it is not normally adapted.
And thus we arrive at another great question. How is it possible to say something that means something? How do we make sense of the world when we speak about it? How can we communicate the essence of what we feel and think about the world? How can we speak in ways that are not misunderstood? What is the correct way to use language?
Chapter5. The end of
At first sight it seems rather extravagant to claim that the way we see the world influences what we think about ourselves. How can that be true? To understand how it is could be the way we picture and see the world influences what we think about ourselves let us begin with the Copernican revolution, which radically changed our sense of our position in the universe. Before Copernicus we located the earth firmly in the center of things. For two thousand years and more human beings had pictured themselves as being contained, like a mandala, within a series of protecting spheres, planetary and divine.
The Christian vision, which dominated thinking throughout the Middle Ages, pictured humanity as the pinnacle of creation. Our task, according to Genesis, was to "subdue the earth." Christ's incarnation and crucifixion were not simply concerned with the fate of human beings but represented a cosmic event at the core of the universe. After the Fall, not only was the human race cast out of the Garden of Eden, but from that moment matter itself also fell from grace and awaited redemption. As Jakob Bohme wrote, "all of creation groans towards the day of fulfillment" and, in Marlow's Faustus the doomed Faustus cries out, "See Christ's blood stream through the firmament." The entire cosmos circled around humanity. Human beings were the descendents of the Fall, and following that Fall the universe entered a state of expectant waiting.
All this changed with the Copernican revolution. Earth was demoted to become just another planet circling the sun and humanity was removed from its throne at the heart and center of the cosmos. Later, following the invention of powerful telescopes, the sun was found to be just another star amongst countless billions. The Copernican revolution therefore produced a dramatic dislocation in our mental map of our place in the scheme of the universe. This shift in our picture of ourselves in relation to the cosmos gave rise to a fracture between inner, psychological space (where we felt ourselves to be) and the way we represented ourselves in relation to the new geometry of the cosmos.
Chaos theory has become ubiquitous, but to discover its origins we must go back to 1900 and a study made by the mathematician and philosopher Henri Poncaré. Poncaré was investigating another of those certainties, one that the human race had lived with since the beginning of time - "the sun will always rise in the morning and set in the evening." In questioning the inevitability of things he was asking if this certainty of earth's orbit around the sun continue to repeat itself? In his researcher Poncaré was touching something very deep, no less than civilizations' entire way of understanding time and what it means to live within a cyclical nature. In doing so he was touching the seeds of chaos, and maybe this is the reason that the term "chaos" and the notion of a Chaos Theory has proved to be so disturbing to a mind that seeks order, regularity and predictability.
This chapter discusses far more pressing issues - the global and local choices we face in our daily life, and decisions that will impact on our children and our children's children. These issues concern aspects of our daily living that our grandparents' generation took for granted but which we have now come to question.
The 19th century had been a time of vast horizons and empty spaces. Question marks could still be found on maps and new lands were being opened to explorers and settlers. Over a century ago people believed that the earth and its resources were unlimited. There were always new materials to be developed and new energy resources to be exploited. There would always be something for everyone. Until the Industrial Revolution when machines acted to amplify human actions, a lifetime of human labor and effort had only a small impact on the earth. It was natural to believe that the human race would persist forever. Thinkers like Nietzsche and Bernard Shaw even believe that humanity was climbing onward and upward towards the age of the Superman.
All this changed during the 20th century. The human race experienced the hubris of its earlier pride and arrogance. This change is symbolized by two remarkable images that have etched themselves deeply into our collective unconscious: a mushroom cloud and a blue ball in space. Both were the result of advances in science and technology. Both subverted our boast that humanity was capable of unlimited advance and progress.
The first, the mushroom cloud, stands for the atomic bomb and the generations of nuclear weapons that followed. For over half a century the world lived under the shadow of this cloud. During that period the Bulletin of Atomic Scientists set its symbolic nuclear clock on its masthead with the hands pointing at five minutes to midnight, indicating that the human race stood on the brink of a nuclear holocaust. Although a generation of American children was taught the nuclear drill of "duck and cover," scientists were soon pointing out the futility of the various emergency measures that had been set in place. The immediate effect of explosions and radiation was bad enough, but what came afterwards would be far worse. As Soviet Premier Nikita Khruschev put it, after a nuclear war the living will envy the dead. Nuclear explosions would create vast dust clouds in the upper atmosphere so thick they would block out the sun's light and heat for years to come. A nuclear winter, a period of cold so profound and unremitting that it would wipe out not only the human race but also most life on earth, would follow.
The tension of the cold war is now behind us. But in a different form a nuclear threat still exists, not so much from the big superpowers but from smaller and less stable nations, and even organized criminal groups. Half a century of international tension has made us more aware of the fragility of life on the planet. Science has revealed other threats, from viruses to drug-resistant microorganisms. Recently a Swedish hospital discovered that Hepatitis C had found a way of spreading to hospital patients not through the normal routes of intravenous injections of contaminated blood but as an airborne virus.
Ebola first emerged from the Ebola River region of Zaire in 1976. The death rate from the disease is 50-90%. There is no known treatment. AIDS is taking a terrible toll and its effect in Africa is proving to be as devastating as the Black Death that swept across medieval Europe. Yet the AIDS virus can only survive under optimum conditions. Imagine what would happen if such a virus could be transmitted by a flea or mosquito bite? Or if it were airborne, as was the case with Hepatitis C in Sweden? Would that spell the end of or global civilization? Human life may be far more vulnerable than we imagined.
The second key image of the 20th century, a photograph taken by American astronauts. is of planet earth as a blue ball suspended in space. The fact that the earth is finite is something we all knew at an intellectual level, yet it required all the billions of dollars spent on the space race to remind us in a forceful way that we are all brothers and sisters. Native Americans say "all my relations," meaning humans, animals, fish, birds, insects, trees, plants, and rocks. That image from space reminded us all that we are inhabitants of a single earth and that its resources are not infinite. What is done in one place effects another. Smoke from the smelters in Sudbury, Northern Ontario, pollutes the North Eastern United States. The rain that fell on my car in central Italy last night left a fine dusting of white mud - it was sand from the Sahara desert carried by the wind.
When it comes to ecology and environmental pollution, there is no room for national politics. Wind does not acknowledge national boundaries, rain falls on international treaties. The destruction of the Amazon rain forests is not an internal matter for the Brazilian government but an issue vital to the climate of the entire world. The choice of a family car or the act of switching on an air conditioner is no longer a matter of purely personal choice. It is on issues like these that the environmental movement takes its stand.
Chapter8 Pausing the
In that same period British children were taught that all those red areas on the map of the world were British colonies and protectorates. The British Empire, they were told, was much vaster than any Empire in the history of the world. It literally spanned the globe, so that the sun would never set on its boundaries. How could such an Empire, based on trade and paternalistic administration, ever falter?
Americans and Europeans alike were inheritors of the great Enlightenment dream whereby people could be improved and society bettered through knowledge and education. The 18th century Enlightenment philosophers had expressed their confidence in the power of reason and the value of progress. They believed it would be possible to eliminate extremes of poverty and inequality. Cities would be orderly, rational places. And, once they had been freed from want, human beings could be counted on to act in the best interests of those around them and treat others as they would wish to be treated themselves. If crime and antisocial behavior were the result of poor housing and faulty social conditions then such ills would be eradicated by rational social planning. With a well-educated and properly informed public, true democracy would be possible.
This dream was based on a set of collectively held certainties, values that everyone espoused - the common good, maximum happiness, reason, free will, good government and the rule of order. It had its seeds in the city states of the past, from Athens of classical Greece, to Florence and Venice of the Renaissance. (That is not to say that other peoples, from the Shang of Ancient China to the Blackfoot and Iroquois confederations in North America, did not also organize themselves wisely).
City states were small enough, and sufficiently compact, for a vibrant democracy to be practiced (although suffrage was by no means universal). A small group of elected officials, responsible to the whole society, could act in an enlightened and responsible way, and make wise and sensible decisions to give society its internal stability and protection from outside disturbance. The citizens of such states were both content and creative. Not only did they practice trade, but they had a love for art, music, literature, and beautiful public buildings. The artist Piero della Francesca, for example, drew up plans for an Ideal City, for, after all, rational people should live in rational spaces. In turn, a city founded on mathematical principles would induce harmonious and orderly behavior in its citizens.
Even the Dionysian elements of human nature were not ignored by such rational societies. Room was made for them so that they did not erupt in an uncontrolled way to threaten peace and order. Venice, and other city states, had their periodic, during which sexual license was permitted, but always within a framework that would contain rule-breaking. By hiding their faces behind masks, for example, anonymity was preserved so that family relationships would remain uncompromised. When, in the 16th century, Venice experienced a rise in the number of male prostitutes, the city avoided any confrontation with the rules of the Church regarding homosexuality by decreeing that a man wearing a female mask was officially a "masked woman" and therefore free from arrest. The forces of human desire were thereby contained though the exercise of wisdom.
The Enlightenment had turned its back on superstition by stressing that "man" is a rational animal. Then came the Utilitarians, John Stuart Mill and Jeremy Bentham, who argued that it was possible to maximize human happiness, just as it is possible to quantify and maximize any other commodity. The eighteenth century also saw the rise of science and an increased faith in the power of knowledge. Its logical outcome was the belief that science and its associated technologies could solve the outstanding problems faced by society. Such problems would be approached in a "scientific way" using logic, knowledge, and the ability to predict the future through mathematics.
The faith in a scientific future reached his heights with such technological optimists as H.G. Wells (although Wells could also see science and the future of human society in a pessimistic light). Human beings would discover inexhaustible sources of free energy; they would live longer; disease and famine would be eliminated; all knowledge would be revealed to us. Thanks to rapid communication and ease of travel we would realize that we inhabit a single world and wars and conflicts would be things of the past. Poverty and inequality would be eliminated and there would be a world government of benevolent technocrats. This was the image of the future at the dawn of the twentieth century.
The Sleep of Reason
The greatest horror is that, after the devastation of two world wars and the constant threat of nuclear annihilation of life on earth, the old patterns of thought continue. Disputes are still resolved by violence and war. In some cases violence is brutal and direct, as with the rape and butchery of populations, in others it takes advantage of high technology to deliver death at a distance with rockets and electronics. It seems that even our most sophisticated science and technology is being put to the service of our most primitive drives and reactions.
Despite all our new knowledge, our science,
courts, the United Nations, and our ability to communicate globally so
that "nation shall speak peace to nation," the terrible mess still
Does this mean that reason and science are insufficient? Is the human
an evolutionary experiment that is now failing to the point where it
well destroy both itself and the environment that supports it? Did
consciousness develop too rapidly to deal with the technologies it
As moral beings, are we doomed to lapse again and again? Is there any
we can be saved?
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