Rationality- From AI to Zombies

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Rationality- From AI to Zombies Page 16

by Eliezer Yudkowsky


  It is a counterintuitive idea that the optimal strategy can be to think lawfully, even under conditions of uncertainty.

  And so there are not many rationalists, for most who perceive a chaotic world will try to fight chaos with chaos. You have to take an extra step, and think of something that doesn’t pop right into your mind, in order to imagine fighting fire with something that is not itself fire.

  You have heard the unenlightened ones say, “Rationality works fine for dealing with rational people, but the world isn’t rational.” But faced with an irrational opponent, throwing away your own reason is not going to help you. There are lawful forms of thought that still generate the best response, even when faced with an opponent who breaks those laws. Decision theory does not burst into flames and die when faced with an opponent who disobeys decision theory.

  This is no more obvious than the idea of betting all blue, faced with a sequence of both blue and red cards. But each bet that you make on red is an expected loss, and so too with every departure from the Way in your own thinking.

  How many Star Trek episodes are thus refuted? How many theories of AI?

  *

  1. Dawes, Rational Choice in An Uncertain World; Yaacov Schul and Ruth Mayo, “Searching for Certainty in an Uncertain World: The Difficulty of Giving Up the Experiential for the Rational Mode of Thinking,” Journal of Behavioral Decision Making 16, no. 2 (2003): 93–106, doi:10.1002/bdm.434.

  2. Amos Tversky and Ward Edwards, “Information versus Reward in Binary Choices,” Journal of Experimental Psychology 71, no. 5 (1966): 680–683, doi:10.1037/h0023123.

  40

  My Wild and Reckless Youth

  It is said that parents do all the things they tell their children not to do, which is how they know not to do them.

  Long ago, in the unthinkably distant past, I was a devoted Traditional Rationalist, conceiving myself skilled according to that kind, yet I knew not the Way of Bayes. When the young Eliezer was confronted with a mysterious-seeming question, the precepts of Traditional Rationality did not stop him from devising a Mysterious Answer. It is, by far, the most embarrassing mistake I made in my life, and I still wince to think of it.

  What was my mysterious answer to a mysterious question? This I will not describe, for it would be a long tale and complicated. I was young, and a mere Traditional Rationalist who knew not the teachings of Tversky and Kahneman. I knew about Occam’s Razor, but not the conjunction fallacy. I thought I could get away with thinking complicated thoughts myself, in the literary style of the complicated thoughts I read in science books, not realizing that correct complexity is only possible when every step is pinned down overwhelmingly. Today, one of the chief pieces of advice I give to aspiring young rationalists is “Do not attempt long chains of reasoning or complicated plans.”

  Nothing more than this need be said: Even after I invented my “answer,” the phenomenon was still a mystery unto me, and possessed the same quality of wondrous impenetrability that it had at the start.

  Make no mistake, that younger Eliezer was not stupid. All the errors of which the young Eliezer was guilty are still being made today by respected scientists in respected journals. It would have taken a subtler skill to protect him than ever he was taught as a Traditional Rationalist.

  Indeed, the young Eliezer diligently and painstakingly followed the injunctions of Traditional Rationality in the course of going astray.

  As a Traditional Rationalist, the young Eliezer was careful to ensure that his Mysterious Answer made a bold prediction of future experience. Namely, I expected future neurologists to discover that neurons were exploiting quantum gravity, a la Sir Roger Penrose. This required neurons to maintain a certain degree of quantum coherence, which was something you could look for, and find or not find. Either you observe that or you don’t, right?

  But my hypothesis made no retrospective predictions. According to Traditional Science, retrospective predictions don’t count—so why bother making them? To a Bayesian, on the other hand, if a hypothesis does not today have a favorable likelihood ratio over “I don’t know,” it raises the question of why you today believe anything more complicated than “I don’t know.” But I knew not the Way of Bayes, so I was not thinking about likelihood ratios or focusing probability density. I had Made a Falsifiable Prediction; was this not the Law?

  As a Traditional Rationalist, the young Eliezer was careful not to believe in magic, mysticism, carbon chauvinism, or anything of that sort. I proudly professed of my Mysterious Answer, “It is just physics like all the rest of physics!” As if you could save magic from being a cognitive isomorph of magic, by calling it quantum gravity. But I knew not the Way of Bayes, and did not see the level on which my idea was isomorphic to magic. I gave my allegiance to physics, but this did not save me; what does probability theory know of allegiances? I avoided everything that Traditional Rationality told me was forbidden, but what was left was still magic.

  Beyond a doubt, my allegiance to Traditional Rationality helped me get out of the hole I dug myself into. If I hadn’t been a Traditional Rationalist, I would have been completely screwed. But Traditional Rationality still wasn’t enough to get it right. It just led me into different mistakes than the ones it had explicitly forbidden.

  When I think about how my younger self very carefully followed the rules of Traditional Rationality in the course of getting the answer wrong, it sheds light on the question of why people who call themselves “rationalists” do not rule the world. You need one whole hell of a lot of rationality before it does anything but lead you into new and interesting mistakes.

  Traditional Rationality is taught as an art, rather than a science; you read the biography of famous physicists describing the lessons life taught them, and you try to do what they tell you to do. But you haven’t lived their lives, and half of what they’re trying to describe is an instinct that has been trained into them.

  The way Traditional Rationality is designed, it would have been acceptable for me to spend thirty years on my silly idea, so long as I succeeded in falsifying it eventually, and was honest with myself about what my theory predicted, and accepted the disproof when it arrived, et cetera. This is enough to let the Ratchet of Science click forward, but it’s a little harsh on the people who waste thirty years of their lives. Traditional Rationality is a walk, not a dance. It’s designed to get you to the truth eventually, and gives you all too much time to smell the flowers along the way.

  Traditional Rationalists can agree to disagree. Traditional Rationality doesn’t have the ideal that thinking is an exact art in which there is only one correct probability estimate given the evidence. In Traditional Rationality, you’re allowed to guess, and then test your guess. But experience has taught me that if you don’t know, and you guess, you’ll end up being wrong.

  The Way of Bayes is also an imprecise art, at least the way I’m holding forth upon it. These essays are still fumbling attempts to put into words lessons that would be better taught by experience. But at least there’s underlying math, plus experimental evidence from cognitive psychology on how humans actually think. Maybe that will be enough to cross the stratospherically high threshold required for a discipline that lets you actually get it right, instead of just constraining you into interesting new mistakes.

  *

  41

  Failing to Learn from History

  Once upon a time, in my wild and reckless youth, when I knew not the Way of Bayes, I gave a Mysterious Answer to a mysterious-seeming question. Many failures occurred in sequence, but one mistake stands out as most critical: My younger self did not realize that solving a mystery should make it feel less confusing. I was trying to explain a Mysterious Phenomenon—which to me meant providing a cause for it, fitting it into an integrated model of reality. Why should this make the phenomenon less Mysterious, when that is its nature? I was trying to explain the Mysterious Phenomenon, not render it (by some impossible alchemy) into a mundane phenomenon, a phenomenon that woul
dn’t even call out for an unusual explanation in the first place.

  As a Traditional Rationalist, I knew the historical tales of astrologers and astronomy, of alchemists and chemistry, of vitalists and biology. But the Mysterious Phenomenon was not like this. It was something new, something stranger, something more difficult, something that ordinary science had failed to explain for centuries—

  —as if stars and matter and life had not been mysteries for hundreds of years and thousands of years, from the dawn of human thought right up until science finally solved them—

  We learn about astronomy and chemistry and biology in school, and it seems to us that these matters have always been the proper realm of science, that they have never been mysterious. When science dares to challenge a new Great Puzzle, the children of that generation are skeptical, for they have never seen science explain something that feels mysterious to them. Science is only good for explaining scientific subjects, like stars and matter and life.

  I thought the lesson of history was that astrologers and alchemists and vitalists had an innate character flaw, a tendency toward mysterianism, which led them to come up with mysterious explanations for non-mysterious subjects. But surely, if a phenomenon really was very weird, a weird explanation might be in order?

  It was only afterward, when I began to see the mundane structure inside the mystery, that I realized whose shoes I was standing in. Only then did I realize how reasonable vitalism had seemed at the time, how surprising and embarrassing had been the universe’s reply of, “Life is mundane, and does not need a weird explanation.”

  We read history but we don’t live it, we don’t experience it. If only I had personally postulated astrological mysteries and then discovered Newtonian mechanics, postulated alchemical mysteries and then discovered chemistry, postulated vitalistic mysteries and then discovered biology. I would have thought of my Mysterious Answer and said to myself: No way am I falling for that again.

  *

  42

  Making History Available

  There is a habit of thought which I call the logical fallacy of generalization from fictional evidence. Journalists who, for example, talk about the Terminator movies in a report on AI, do not usually treat Terminator as a prophecy or fixed truth. But the movie is recalled—is available—as if it were an illustrative historical case. As if the journalist had seen it happen on some other planet, so that it might well happen here. More on this in Section 7 of ”Cognitive biases potentially affecting judgment of global risks.”1

  There is an inverse error to generalizing from fictional evidence: failing to be sufficiently moved by historical evidence. The trouble with generalizing from fictional evidence is that it is fiction—it never actually happened. It’s not drawn from the same distribution as this, our real universe; fiction differs from reality in systematic ways. But history has happened, and should be available.

  In our ancestral environment, there were no movies; what you saw with your own eyes was true. Is it any wonder that fictions we see in lifelike moving pictures have too great an impact on us? Conversely, things that really happened, we encounter as ink on paper; they happened, but we never saw them happen. We don’t remember them happening to us.

  The inverse error is to treat history as mere story, process it with the same part of your mind that handles the novels you read. You may say with your lips that it is “truth,” rather than “fiction,” but that doesn’t mean you are being moved as much as you should be. Many biases involve being insufficiently moved by dry, abstract information.

  Once upon a time, I gave a Mysterious Answer to a mysterious question, not realizing that I was making exactly the same mistake as astrologers devising mystical explanations for the stars, or alchemists devising magical properties of matter, or vitalists postulating an opaque “élan vital” to explain all of biology.

  When I finally realized whose shoes I was standing in, there was a sudden shock of unexpected connection with the past. I realized that the invention and destruction of vitalism—which I had only read about in books—had actually happened to real people, who experienced it much the same way I experienced the invention and destruction of my own mysterious answer. And I also realized that if I had actually experienced the past—if I had lived through past scientific revolutions myself, rather than reading about them in history books—I probably would not have made the same mistake again. I would not have come up with another mysterious answer; the first thousand lessons would have hammered home the moral.

  So (I thought), to feel sufficiently the force of history, I should try to approximate the thoughts of an Eliezer who had lived through history—I should try to think as if everything I read about in history books had actually happened to me. (With appropriate reweighting for the availability bias of history books—I should remember being a thousand peasants for every ruler.) I should immerse myself in history, imagine living through eras I only saw as ink on paper.

  Why should I remember the Wright Brothers’ first flight? I was not there. But as a rationalist, could I dare to not remember, when the event actually happened? Is there so much difference between seeing an event through your eyes—which is actually a causal chain involving reflected photons, not a direct connection—and seeing an event through a history book? Photons and history books both descend by causal chains from the event itself.

  I had to overcome the false amnesia of being born at a particular time. I had to recall—make available—all the memories, not just the memories which, by mere coincidence, belonged to myself and my own era.

  The Earth became older, of a sudden.

  To my former memory, the United States had always existed—there was never a time when there was no United States. I had not remembered, until that time, how the Roman Empire rose, and brought peace and order, and lasted through so many centuries, until I forgot that things had ever been otherwise; and yet the Empire fell, and barbarians overran my city, and the learning that I had possessed was lost. The modern world became more fragile to my eyes; it was not the first modern world.

  So many mistakes, made over and over and over again, because I did not remember making them, in every era I never lived . . .

  And to think, people sometimes wonder if overcoming bias is important.

  Don’t you remember how many times your biases have killed you? You don’t? I’ve noticed that sudden amnesia often follows a fatal mistake. But take it from me, it happened. I remember; I wasn’t there.

  So the next time you doubt the strangeness of the future, remember how you were born in a hunter-gatherer tribe ten thousand years ago, when no one knew of Science at all. Remember how you were shocked, to the depths of your being, when Science explained the great and terrible sacred mysteries that you once revered so highly. Remember how you once believed that you could fly by eating the right mushrooms, and then you accepted with disappointment that you would never fly, and then you flew. Remember how you had always thought that slavery was right and proper, and then you changed your mind. Don’t imagine how you could have predicted the change, for that is amnesia. Remember that, in fact, you did not guess. Remember how, century after century, the world changed in ways you did not guess.

  Maybe then you will be less shocked by what happens next.

  *

  1. Eliezer Yudkowsky, “Cognitive Biases Potentially Affecting Judgment of Global Risks,” in Global Catastrophic Risks, ed. Nick Bostrom and Milan M. Ćirković (New York: Oxford University Press, 2008), 91–119.

  43

  Explain/Worship/Ignore?

  As our tribe wanders through the grasslands, searching for fruit trees and prey, it happens every now and then that water pours down from the sky.

  “Why does water sometimes fall from the sky?” I ask the bearded wise man of our tribe.

  He thinks for a moment, this question having never occurred to him before, and then says, “From time to time, the sky spirits battle, and when they do, their blood drips from the sky.”

>   “Where do the sky spirits come from?” I ask.

  His voice drops to a whisper. “From the before time. From the long long ago.”

  When it rains, and you don’t know why, you have several options. First, you could simply not ask why—not follow up on the question, or never think of the question in the first place. This is the Ignore command, which the bearded wise man originally selected. Second, you could try to devise some sort of explanation, the Explain command, as the bearded man did in response to your first question. Third, you could enjoy the sensation of mysteriousness—the Worship command.

  Now, as you are bound to notice from this story, each time you select Explain, the best-case scenario is that you get an explanation, such as “sky spirits.” But then this explanation itself is subject to the same dilemma—Explain, Worship, or Ignore? Each time you hit Explain, science grinds for a while, returns an explanation, and then another dialog box pops up. As good rationalists, we feel duty-bound to keep hitting Explain, but it seems like a road that has no end.

  You hit Explain for life, and get chemistry; you hit Explain for chemistry, and get atoms; you hit Explain for atoms, and get electrons and nuclei; you hit Explain for nuclei, and get quantum chromodynamics and quarks; you hit Explain for how the quarks got there, and get back the Big Bang . . .

  We can hit Explain for the Big Bang, and wait while science grinds through its process, and maybe someday it will return a perfectly good explanation. But then that will just bring up another dialog box. So, if we continue long enough, we must come to a special dialog box, a new option, an Explanation That Needs No Explanation, a place where the chain ends—and this, maybe, is the only explanation worth knowing.

  There—I just hit Worship.

 

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