Bedeviled

A Shadow History of Demons in Science

Jimena Canales

• Verlag: Princeton University Press
• Jahr: 2020
• ISBN:
  9780691186078
• Thema: History
• Thema: Science History

How scientists through the ages have conducted thought experiments using imaginary entities—demons—to test the laws of nature and push the frontiers of what is possible Science may be known for banishing the demons of superstition from the modern world. Yet just as the demon-haunted world was being exorcized by the enlightening power of reason, a new kind of demon mischievously materialized in the scientific imagination itself. Scientists began to employ hypothetical beings to perform certain roles in thought experiments—experiments that can only be done in the imagination—and these impish assistants helped scientists achieve major breakthroughs that pushed forward the frontiers of science and technology.Spanning four centuries of discovery—from René Descartes, whose demon could hijack sensorial reality, to James Clerk Maxwell, whose molecular-sized demon deftly broke the second law of thermodynamics, to Darwin, Einstein, Feynman, and beyond—Jimena Canales tells a shadow history of science and the demons that bedevil it. She reveals how the greatest scientific thinkers used demons to explore problems, test the limits of what is possible, and better understand nature. Their imaginary familiars helped unlock the secrets of entropy, heredity, relativity, quantum mechanics, and other scientific wonders—and continue to inspire breakthroughs in the realms of computer science, artificial intelligence, and economics today.The world may no longer be haunted as it once was, but the demons of the scientific imagination are alive and well, continuing to play a vital role in scientists' efforts to explore the unknown and make the impossible real.

1

Descartes’s Evil Genius

Volumes have been written about a demon first imagined in 1641 by the French philosopher René Descartes. Descartes described a creature, using the Latin term malignum genium, who could remove the world in front of us and provide us with an alternative reality. By reminding us that all we perceive might be a lie, or the bad joke of an intelligence higher than ours, Descartes’s creation planted the seed of doubt firmly in our minds. Against it, we have developed tools and techniques to better understand the imperfection of our senses and to exploit the power of pure reason. Yet we also turn these insights against ourselves, when we use them to find ever more perfect ways of imitating reality to fool others.

Descartes’s demon is not alone—he inspired many other thinkers to search for others like him. Today he is the darling of magicians, advertisement executives, spin doctors, and the entertainment and media industry. He is presently most feared for his ability to spread fake news and create deepfakes. Descartes’s creation saddled us with the responsibility of making reason our master. It challenged us to advance knowledge by questioning our dearest assumptions, everything and everyone, including social, religious, and political authorities.

Thanks to him, skepticism and doubt continue to be the most powerful tools of scientific discovery.

“I always had an extreme desire to learn to distinguish the true from the false,” wrote the philosopher René Descartes in his Discourse on the Method.¹ The year was 1637. The task was not easy. Folk practices for judging reality and for distinguishing truth from superstition seemed perilously faulty, unsystematic, unreliable, and subject to error. Could they be replaced by a better, maybe even entirely rational method? Descartes worked hard to find ways to deliver us from a world of maddening illusions—to discover a method for distinguishing fact from fiction and separating sanity from insanity. He articulated the best techniques he could think of. The process he came up with earned him the distinction of being the founder of modern philosophy and the father of rationalism. Scholars usually associate the beginning of the Age of Reason with his work, which is widely considered to mark the beginning of the natural sciences and to have inspired the materialist and secular philosophies that would characterize the following centuries.

The Cartesian era was one of brain over brawn. It proved to be exciting and wonderfully creative. Descartes gave his readers detailed instructions for how to fend off the demon who would carry his name. His demon’s weakness resided in his inability to fiddle with certain basic facts, beginning with the inescapable reality that if one thinks then one must be. “I think therefore I am,” stressed the philosopher, writing for the first time the original Latin phrase cogito ergo sum that to this day is widely recognized.

Descartes’s solution was to focus on the most certain truths he could find in an otherwise confusing and tricky world. “Two and three added together are five,” he wrote excitedly in his First Meditation. “A square has no more than four sides,” he continued.² From simple examples like these, he sought to build up a method for determining all other ineluctable “transparent” truths. These, he hoped, could serve as a firm foundation for understanding the world in a thoroughly rational manner. This analysis seemed to be going swimmingly, until the demon named after Descartes revealed just how hard it would be to draw a firm line between the real and the unreal. His tricks were sometimes so perfect that victims would remain unaware that what they perceived as ineluctable truth was fraught.

Descartes’s demon could capture you by throwing a cloak over your head and, like a talented kidnapper, severing you from reality, before tossing you an alternative one. He could intercept all inputs leading to your brain, hijacking the source of your sensory impressions. In the nightmare scenario known as “the brain in the vat” thought experiment, which was widely used by neurophysiologists and philosophers to illustrate how thinking works, a thinking organ could be fooled into believing in an inexistent reality. Descartes’s writings fueled many later speculations about what an isolated brain might think, feel, and sense. What might go on in a brain that is cut away and separated from its body and senses? Are we justified in fearing an evil being who might cultivate our worthy organ in a soup bowl? Philosophers today often explain the power of Descartes’s manipulating demon by asking these questions. They wonder if a prankster or scientist could manipulate the input to the pink-grayish lump of neurons floating in some greenish-blue liquid and conceal from the victim the terrifying reality of their truly lamentable blobby condition.

After it was first invoked, Descartes’s savvy illusionist became a symbol for the ultimate trickster: a trafficker between fiction and nonfiction, much like an ideal magician who can operate without smoke and mirrors. As the master of trompe l’oeil, he represents the promises and perils of virtual reality. Because of him, we have become increasingly aware that we can only know the world as if through a glass darkly. Descartes’s demon offers the promises of virtual reality minus the headset or screen. More than the stuff of nightmares, this professional hoodwinker gives us daymares. He is a threat—and an inspiration—to scientists, artists, engineers, and con men. At any moment, the heavens, a landscape, or a seascape could become his simulacrum, his favorite playground. In Descartes’s conceptualization, the elements constituting our universe might be nothing but props in a demon’s fabulous show. Nature might simply be the most wonderful spectacle that could ever be, one practically indistinguishable from nonspectacle. How could anyone, even astronomers trying to uncover the secrets of our universe, resist being hypnotized by the beauty of the starry skies? Descartes fanned fears that perhaps we are all living in an immense production courtesy of our defective senses.

But the powers of Descartes’s demon were found to be limited. He could reach only as far in as the retina. He could gaslight us only through our senses and did not mess with our brains directly. Faced with the power of our minds, his strength dwindled. His theatrical skills were indeed deep, but his knowledge of neurophysiology and chemistry was shallow. It would take years for scientists to conceive of another demon who could manipulate atoms, another one who could mess with photons, yet another who could control our bodies, and an even craftier one who could implant itself directly in our brains.

Descartes’s demon was central to the foundation of cerebral personhood. As attention shifted to the power of our brains, our bodies were devalued as machines in its service. Descartes famously argued in his Principles of Philosophy (1644) that he could “not recognize any difference between artefacts and natural bodies.”³ In the Cartesian conception of the universe, sometimes referred to as the “Cartesian Theater,” the universe was divided into mind and matter. This dualistic conceptualization—and the demon that led to it—arose in connection with the development of modern media, starting with early theater and print.

DON QUIXOTE’S WINDMILLS AND OTHER DEMONS

A well-known character in Descartes’s time who was particularly confused about truth and falsehood was the famous Don Quixote de la Mancha. Scholars are quite certain that Descartes must have read Don Quixote by Miguel de Cervantes. It is likely that his exposure to the novel, alongside other works of his era exploring similar themes, played a role in fueling his obsession with drawing out and systematizing the laws of reason.⁴ Descartes seemed to be concerned by how easily an unreal world had supplanted the hero’s sense of reality. In the novel, the old geezer went off traveling on the plains of La Mancha with the confidence of a handsome young knight. Mounted on the feeble donkey Rocinante, he thought he was riding a beautiful stallion. Flirting with the rustic Aldonza, he was convinced that he was conquering the sweet princess Dulcinea. Charging violently at windmills, he was fighting giants. Taken into custody by well-meaning gentlemen, he was convinced that he was being kidnapped by demons. All the while, he and his faithful squire Sancho Panza famously disagreed about donkeys and horses, damsels and ladies, windmills and giants, gentlemen and demons.

Descartes warned against the dangers of reading novels such as those that fascinated Quixote and a growing public. He was specifically concerned about the “most accurate histories” of valiant knights. If Don Quixote was knocked off his rocker by reading too many chivalric histories, other readers could suffer a similar fate by following in his steps. “Those who regulate their conduct by examples drawn from these works,” Descartes warned, “are liable to fall into the excesses of the knights-errant in our tales of chivalry, and conceive plans beyond their powers.” “Fables” were just as dangerous, he cautioned, since they could also warp the sense of reality of gullible readers. They “make us imagine many events as possible when they are not,” he explained.⁵

Miguel de Cervantes might have been responsible for these and other crimes. He took his readers along on a doubly perverse adventure. By writing a best-seller readers could barely put down, he got them hooked on a work of fiction about a man who had been permanently damaged by becoming hooked himself on fictions.

“They are demons that have taken fantastic shapes,” exclaimed Quixote, caged and confused, facing a clear upset during his chivalric adventures.⁶ The valiant knight was carted away from the vast expanses of La Mancha by a group of gentlemen who thought he was unhinged and perhaps a tad dangerous. His delicate mind told him that his captors were “all demons.” But his general assessment of the dire situation was not all that clear. Why were they traveling so slowly in a rickety, uncomfortable, ox-driven cart? Storied accounts of such sequestrations tended to feature fancier means of transportation. Quixote expressed his surprise to Sancho. Why were they not whisked “away through the air with marvelous swiftness, enveloped in a dark thick cloud, or on a chariot of fire, or it may be on some hippogriff or other beast of the kind”?⁷

And who were those men—or from the perspective of the lanky master, those demons—who now seemed to control their fates? Cervantes’s endearing Quixote sees them, although his faithful squire does not. A proclivity to see demons serves as a litmus test, a kind of barometer, through which readers can gauge the mental fitness of the two friends. In the novel, Sancho was a salutary counterpart to overzealous Torquemadas—believers who found evidence of the angelic or the demonic in every nook and crack, in every unpredictable event, and who felt justified in glorifying or violently persecuting every minor insinuation of otherworldly presences. Sancho is a sort of proto-scientist who brushed superstitions aside pragmatically; a no-nonsense commoner, his congenital simplicity led him to be more in touch with reality than his noble master, who confronted the world, not through his senses and fingers, but only indirectly by poking his lance (and other protuberances) where he should not.

The faithful servant perceived the men taking them away as regular flesh-and-blood mortals. Don Quixote thought otherwise. Could the discrepancy between them be resolved? Quixote urged Sancho to corroborate his thesis experimentally:

And if you want to see this truth, touch them and feel them, and you will see how they do not have bodies but are air and do not consist of anything but appearances.⁸

In the novel, the act of testing Quixote’s demon hypothesis by touching his captors did not change the belief structure of either man. Sancho responded to his master by saying that he had already touched them and smelled them, and that they were burly men who smelled of sweet amber perfume. If they were demons, they would smell of sulfur, Quixote insisted, and if these particular beings did not, it was only because of some clever ruse; perhaps they had disguised themselves with perfume.

Cervantes’s story is thus very much the opposite of the biblical story in the Gospel of John, where the Apostle Thomas had his doubts about the resurrection dispelled when he touched Christ’s wound. To Quixote, touching was no longer any good. The experiment made no difference. It only confirmed what Sancho already knew and what Quixote already believed. The Don was not brought any closer to the squire’s views. There was no epistemic resolution. Cervantes offered readers no possible means through which his characters could be freed from their illusions. The story unravels as a comic tragedy that in the end leads readers to question their own sense of reality and even their own existence. By offering them a story within a story, he asked readers to consider whether perhaps we are all dupes of our own minds caught in an infinite hall of mirrors. Through the realistic dialogue between someone who saw demons and someone who did not, Cervantes invited us to laugh with devilish glee at every turn of the page as we question our own wits. Might we just be characters in a comic novel written by somebody else?

Shakespeare became fascinated by these same questions. He portrayed Hamlet, who was bewildered by the vision of a ghost appearing to be his deceased father, as someone who read too much. The habit had put his mental health in danger. Hamlet also read too much into the world around him, including the clouds in the sky. “Do you see yonder clowd in the shape of a camell?” he asked Polonius, who politely assented: “’Tis like a camell, indeed.” Hamlet quickly changed his mind. “Now me thinkes it’s like a weasel,” and Polonius agreed once more: “’Tis back’t like a weasel.” “Or like a whale?” “Very like a whale,” responded his obsequious friend. Like the vision of the ghost Hamlet could not shake from his mind, other things he saw confounded him as well. How could he rein in his imagination and regain clarity? The corroborations offered by his friends were not helpful. Groupthink led all of these young men astray.⁹

During Elizabethan times, Shakespeare and other dramatists honed their writing skills to fool us into taking in their theatrical creations as real. In the new brick-and-mortar venu...

Inhaltsverzeichnis

• Cover
• Praise
• Title Page
• Copyright
• Dedication
• Contents
• Preface
• Introduction
• 1. Descartes’s Evil Genius
• 2. Laplace’s Intelligence
• 3. Maxwell’s Demon
• 4. Brownian Motion Demons
• 5. Einstein’s Ghosts
• 6. Quantum Demons
• 7. Cybernetic Metastable Demons
• 8. Computer Daemons
• 9. Biology’s Demons
• 10. Demons in the Global Economy
• Conclusion: The Audacity of Our Imagination
• Postscript: Philosophical Considerations
• Notes
• Bibliography
• Index