Osgood conducted an experiment. He asked people to rate twenty concepts on fifty different scales. So did the scales, which were defined by opposites: fair-unfair, hot-cold, fragrant-foul. But the idea was that the method would reveal fine and even elusive shades of similarity and difference among concepts.
His surveys found that, at least for nineteen-fifties college students, the two concepts overlapped much of the time. They diverged for nouns that had a male or female slant.
Osgood became known not for the results of his surveys but for the method he invented to analyze them. He began by arranging his data in an imaginary space with fifty dimensions—one for fair-unfair, a second for hot-cold, a third for fragrant-foul, and so on. Any given concept, like TORNADO , had a rating on each dimension—and, therefore, was situated in what was known as high-dimensional space. Many concepts had similar locations on multiple axes: kind-cruel and honest-dishonest, for instance.
Osgood combined these dimensions. When you reduce a sauce, you meld and deepen the essential flavors. Osgood did something similar with factor analysis. Eventually, he was able to map all the concepts onto a space with just three dimensions. Osgood could use these three key factors to locate any concept in an abstract space. This was an obstacle for computer users, who accessed programs by typing words on a command line. Instead of surveying undergraduates, they used computers to analyze the words in about two thousand technical reports.
The reports themselves—on topics ranging from graph theory to user-interface design—suggested the dimensions of the space; when multiple reports used similar groups of words, their dimensions could be combined. It had a few hundred dimensions. At first, Bell Labs used L. Perhaps my brain uses factor analysis to distill thousands of attributes—height, fashion sense, tone of voice—into a single point in an abstract space.
The perception of bad-guy-ness becomes a matter of proximity. In the following years, scientists applied L. In , researchers at Google unleashed a descendant of it onto the text of the whole World Wide Web.
Other companies, including Apple and Amazon, built similar systems. The technique has become so central to the field of artificial intelligence that, in , a new, hundred-and-thirty-five-million-dollar A. In , a scientist named Jim Haxby brought machine learning to brain imaging: he realized that voxels of neural activity could serve as dimensions in a kind of thought space.
Haxby went on to work at Princeton, where he collaborated with Norman. The two scientists, together with other researchers, concluded that just a few hundred dimensions were sufficient to capture the shades of similarity and difference in most fMRI data. At the Princeton lab, the young woman watched the slide show in the scanner. With each new image—beach, cave, forest—her neurons fired in a new pattern. These patterns would be recorded as voxels, then processed by software and transformed into vectors.
The images had been chosen because their vectors would end up far apart from one another: they were good landmarks for making a map. Watching the images, my mind was taking a trip through thought space, too. The larger goal of thought decoding is to understand how our brains mirror the world. Norman told me that his Princeton colleague Uri Hasson has found movies especially useful in this regard. Jerry hangs up, to cheers from the studio audience. Norman showed the class a series of slides.
Others would be more stable, such as those representing a character in the show. The study confirmed these predictions. But Baldassano also found groups of voxels that held a stable pattern throughout each scene, then switched when it was over. It turned out that no matter whether someone watched a scene, described it, or heard about it, the same voxel patterns recurred.
Through decades of experimental work, Norman told me later, psychologists have established the importance of scripts and scenes to our intelligence. Walking into a room, you might forget why you came in; this happens, researchers say, because passing through the doorway brings one mental scene to a close and opens another.
In a recent P. The scripts and the scenes were real—it was possible to detect them with a machine. What most interests Norman now is how they are learned in the first place. How do we identify the scenes in a story? When we enter a strange airport, how do we know intuitively where to look for the security line?
But at some point everything was new. When I was a toddler, my parents must have taken me to the supermarket for the first time; the fact that, today, all supermarkets are somehow familiar dims the strangeness of that experience. When I was learning to drive, it was overwhelming: each intersection and lane change seemed chaotic in its own way. Now I hardly have to think about them. My mind instantly factors out all but the important differences. Norman clicked through the last of his slides.
Afterward, a few students wandered over to the lectern, hoping for an audience with him. For the rest of us, the scene was over. We packed up, climbed the stairs, and walked into the afternoon sun. The system learned which brain patterns were evoked by certain words, and used that knowledge to guess which words were implied by the new patterns it encountered. If you knew how knowledge was represented in the brain, you might be able to distinguish between novice and expert intelligence agents.
Later, to query the database, someone else could sit in the scanner and simply think of whatever she wanted. It would be the ultimate solution to the vocabulary problem. Jack Gallant, a professor at Berkeley who has used thought decoding to reconstruct video montages from brain scans—as you watch a video in the scanner, the system pulls up frames from similar YouTube clips, based only on your voxel patterns—suggested that one group of people interested in decoding were Silicon Valley investors.
He imagined a company paying people thirty thousand dollars a year to wear the thinking hat, along with video-recording eyeglasses and other sensors, allowing the system to record everything they see, hear, and think, ultimately creating an exhaustive inventory of the mind.
Wearing the thinking hat, you could ask your computer a question just by imagining the words. Instantaneous translation might be possible. In theory, a pair of wearers could skip language altogether, conversing directly, mind to mind. Perhaps we could even communicate across species. There are efforts under way to make powerful miniature imaging devices, using lasers, ultrasound, or even microwaves. Still, the conceptual foundation, which goes back to the nineteen-fifties, has been laid.
Recently, I asked Owen what the new thought-decoding technology meant for locked-in patients. Were they close to having fluent conversations using something like the general-purpose thought decoder?
Can you get robust enough data? On the left side? I have no doubt that, some point down the line, we will be able to read minds. In some ways, the story of thought decoding is reminiscent of the history of our understanding of the gene.
As late as the nineteen-fifties, biologists were still asking what, exactly, a gene was made of. When James Watson and Francis Crick finally found the double helix, in , it became clear how genes took physical form. Fifty years later, we could sequence the human genome; today, we can edit it. Thoughts have been an abstraction for far longer. But now we know what they really are: patterns of neural activation that correspond to points in meaning space.
The mind—the only truly private place—has become inspectable from the outside. In the future, a therapist, wanting to understand how your relationships run awry, might examine the dimensions of the patterns your brain falls into.
With more fine-grained control, a mind could be driven wherever one liked. When the civil war resumed, after the Second World War, both sides conscripted men. He rose to the rank of company commander in the Eighth Route Army, and, after the Communist victory, he began his career in Beijing.
Liu was three years old when the Cultural Revolution broke out. His father lost his job—having a brother who had fought against the revolution made him politically suspect—and was sent to work in the coal mines of Yangquan, in Shanxi Province, where Liu still lives. The city was a flash point for the factional violence that accompanied the Cultural Revolution, and Liu remembers hearing gunfire at night and seeing trucks filled with men clutching guns and wearing red armbands.
Things became dangerous enough that, when Liu was four, he was sent to live with his grandparents in Henan, and stayed there for several years. As a child, Liu was mischievous and cheeky. Even today, he retains a fondness for ingenious pranks, and once created a poetry-writing algorithm, whose voluminous output he submitted to a literary magazine. He also had a practical bent: after developing a fascination with weapons, in grade school, he taught himself to make gunpowder. When Liu was six, China launched its first satellite and he became obsessed with space.
Initially, his ambition was to explore it rather than to write about it, but he came to realize that, for someone of his background, the advanced degrees necessary to work in the nascent space program were out of reach. After graduation, he was assigned to work at the Niangziguan Power Plant, where he had plenty of time to hone his writing and to absorb all the sci-fi he could get his hands on, sometimes poring over a dictionary to get through untranslated works by Vonnegut, Bradbury, Pynchon, and Orwell.
In the nineties, tens of millions of workers found themselves laid off, with no social-security system. Pragmatic choices like this one, or like the decision his grandparents made when their sons were conscripted, recur in his fiction—situations that present equally unconscionable choices on either side of a moral fulcrum.
An episode in the trilogy depicts Earth on the verge of destruction. A scientist named Cheng Xin encounters a gaggle of schoolchildren as she and an assistant prepare to flee the planet. Her assistant leaps into action, however, and poses three math problems. The three children who are quickest to answer correctly are ushered on board.
I gave them a chance. Competition is necessary for survival. No one is more aware than Liu of the connection between the ambitions of sci-fi and the tendency of Chinese history to eclipse the individual. In a single day, forty inches of rain fell and more than fifty dams collapsed. In the course of a few days, nearly a quarter of a million people died. The great flourishing of science fiction in the West at the end of the nineteenth century occurred alongside unprecedented technological progress and the proliferation of the popular press—transformations that were fundamental to the development of the genre.
As the British Empire expanded and the United States began to assert its power around the world, British and American writers invented tales of space travel as seen through a lens of imperial appropriation, in which technological superiority brought about territorial conquest. Extraterrestrials were often a proxy for human beings of different creeds or races. Early Chinese sci-fi imagined a China that caught up with the West and then outstripped it. But during the Cultural Revolution the genre was banned, along with other nonrevolutionary literature, and even science itself was subjected to ideological-purity tests.
Speculative fiction is the art of imagining alternative worlds, and the same political establishment that permits it to be used as propaganda for the existing regime is also likely to recognize its capacity to interrogate the legitimacy of the status quo.
When questioned about stories that seemed to allude to Stalinist conformism and paranoia, Lem said the same thing that Liu says about geopolitical interpretations of his trilogy—that he was not writing a veiled assessment of the present but merely making up stories. One day, Liu and I went to lunch at a Chinese restaurant not far from his hotel.
It was half past two and the restaurant was empty, a void of crisp white tablecloths, punctuated by tacky, oversized ceramic vases. Large TV screens burbled to themselves in every corner.
As soon as we sat down, Liu called a waiter over and asked for two beers. He had bought the bottle the day before at a liquor store. You know the type. Types are central to the way Liu thinks of people; he has a knack for quickly sketching the various classes that make up Chinese society.
Liu readily admits to the charge. Reading an article about the problem, Liu thought, What if the three bodies were three suns? How would intelligent life on a planet in such a solar system develop? From there, a structure gradually took shape that almost resembles a planetary system, with characters orbiting the central conceit like moons.
For better or worse, the characters exist to support the framework of the story rather than to live as individuals on the page. The time line of the trilogy spans 18,, years, encompassing ancient Egypt, the Qin dynasty, the Byzantine Empire, the Cultural Revolution, the present, and a time eighteen million years in the future. One scene is told from the perspective of an ant. The first book is set on Earth, though some of its scenes take place in virtual reality; by the end of the third book, the scope of the action is interstellar and annihilation unfolds across several dimensions.
At every turn, the characters are forced to make brutal calculations in which moral absolutism is pitted against the greater good. In their pursuit of survival, men and women employ Machiavellian game theory and adopt a bleak consequentialism.
The drinks had warmed him, and the heat of Sichuanese peppercorns seemed to stir him from his usual reticence. I decided to inch the conversation toward politics, a topic he prefers to avoid. His views turned out to be staunch and unequivocal. There were reports of elderly people committing suicide in order to be buried before the ban went into effect. If anything, the government is helping their economy and trying to lift them out of poverty.
Not democracy. I looked at him, studying his face. The society of resettled populations transformed in profound ways. People realized that, on this crowded, hungry continent, democracy was more terrifying than despotism. Everyone yearned for order and a strong government. Gradually, the society of the resettled succumbed to the seduction of totalitarianism, like the surface of a lake caught in a cold spell.
It was an opinion entirely consistent with his systems-level view of human societies, just as mine reflected a belief in democracy and individualism as principles to be upheld regardless of outcomes.
Reality brands each of us with its indelible mark. Every era puts invisible shackles on those who have lived through it, and I can only dance in my chains. But at the Clarke Foundation award ceremony, at the Harman Center for the Arts, on his final night in Washington, he was in adult, professional mode.
Yet, at the same time, he seemed ill at ease and looked like the person who least belonged at the party, even though it was in his honor.
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