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Collected Essays

Page 39

by Rucker, Rudy


  (Let me insert a deflationary side-remark on the Singularity that’s supposed to occur when intelligent computers begin designing even more intelligent computers and so on. Perhaps the end result of this kind of process won’t be a god. Perhaps it’ll be something more like a wind-riffled pond, a campfire, or a fly buzzing around your backyard. Nature is, after all, already computing at the maximum possible flop.)

  Now let’s get into my own thought experiment. If we could harness a natural system to act as a computer for us, we’d have what you might call a paracomputer that totally outstrips anything that our man-made beige buzzing desktop machines can do. I say “paracomputer” not “computer” to point out the fact that this is a natural object which behaves like computer, as opposed to being a high-tech totem that we clever monkeys made. Wolfram’s PCE suggests that essentially any gnarly natural process could be used as a paracomputer.

  A natural paracomputer would be powerful enough to be in striking range of predicting other natural systems in real time or perhaps even a bit faster than real time. The problem with our naturally-occurring paracomputers is that they’re not set up for the kinds of tasks we like to use computers for—like predicting the stock-market, rendering Homer Simpson, or simulating nuclear explosions.

  To make practical use of paracomputers we need a solution to what you might call the codec or coding-decoding problem. If you want to learn something specific from a simulation, you have to know how to code your data into the simulation and how to decode it back out. Like suppose you’re going to make predictions about the weather by reading tea-leaves. To get concrete answers, you code today’s weather into a cup of tea, which you’re using as a paracomputer. You swirl the cup around, drink the tea, look at the leaves, and decode the leaf pattern into tomorrow’s weather. Codec.

  This is a subtle point, so let me state it again. Suppose that you want to simulate the market price of a certain stock, and that you have all the data and equations to do it, but the simulation is so complicated that it requires much more time than the real-time period you want to simulate. And you’d like to turn this computation into, say, the motions of some wine when you pour it back and forth between two glasses. You know the computational power is there in the moving wine. But where’s the codec? How do you feed the market trends into the wine? How do you get the prediction numbers out? Do you drink the paracomputer?

  Finding the codec that makes a given paracomputer useful for a particular task is a hard problem, but once you have the codec, your paracomputer can solve things very fast. But how to find the codec? Well, let’s use an SF cheat, let’s suppose that one of the characters in our thought experiment is, oh, a mathematical genius who creates a really clever algorithm for rapidly finding codecs that are, if not perfect, at least robust enough for practical use.

  So now suppose that we’re able, for instance, to program the wind in the trees and use it as a paracomputer. Then what? For the next stage of my thought experiment, I’m thinking about a curious real-world limitative result that could come into play. This is the Margolus-Levitin theorem, which says that there’s some maximum computational rate that any limited region of spacetime can perform at any given energy level. (See for instance Seth Lloyd’s paper, “The Computational Capacity of the Universe”.) The limit is pretty high—some ten-to-the-fiftieth bit-flips per second on a room-temperature laptop—but SF writers love breaking limits.

  In the situation I’m visualizing, a couple of crazy mathematicians (some things never change!) make a paracomputer from a vibrating membrane, use clever logic to find desired codecs, and set the paracomputer to predicting it’s own outputs. I expect the feedback process to produce an ever-increasing amount of computation within the little paracomputer. The result is that the device is on the point of violating the Margolus-Levitin limit, and perhaps the way the universe copes with this is by bulging out a big extra hump of spacetime in the vicinity of the paracomputer. And this hump acts as—a tunnel to a higher universe inhabited by, of course, super-intelligent humanoid cockroaches and carnivorous flying cone shell mollusks!

  Now let’s turn the hard-SF knob up to eleven. Even if we had natural paracomputers, we’d still be limited by the PCU, the principle that most naturally occurring computations are unpredictable. Your paracomputers can speed things up by a linear factor because they’re so massively parallel. Nevertheless, by the PCU, most problems would resist being absolutely crushed by clever shortcuts. The power of the paracomputer may indeed let you predict tomorrow’s weather, but eventually the PCU catches up with you. You still can’t predict, say, next week’s weather. Even with a paracomputer you might be able to approximately predict a person’s activities for half an hour, but not to a huge degree of accuracy, and certainly not out to a time several months away. The PCU makes prediction impossible for extended periods of time.

  Now, being a science-fiction writer, when I see a natural principle, I wonder if it could fail. Even if it’s a principle such as the PCU that I think is true. (An inspiration here is a story by Robert Coates, “The Law,” in which the law of averages fails. The story first appeared in the New Yorker of Nov 29, 1947, and can also be found in Clifton Fadiman’s The Mathematical Magpie.)

  So now let’s suppose that, for their own veiled reasons, the alien cockroaches and cone shells teach our mathematician heroes some amazing new technique that voids the PCU! This notion isn’t utterly inconceivable. Consider, for instance, how drastically the use of language speeds up the human thought process. Or the way that using digital notion speeds up arithmetic. Maybe there’s some thought tool we’ve never even dreamed of that can in fact crush any possible computation into a few quick chicken-scratches on the back of a business card. So our heroes learn this trick and they come back to spread the word.

  And then we’ve got a world where the PCU fails. This is a reality where we can rapidly predict all kinds of things arbitrarily far into the future: weather, moods, stocks, health. A world where people have oracles. SF is all about making things immediate and tactile, so let’s suppose that a oracle is like a magic mirror. You look into it and ask it a question about the future, and it always gives you the right answer. Nice simple interface. What would it be like to live in a world with oracles?

  I’m not sure yet. I’m still computing the outcome of this sequence of thought experiments—the computation consists of writing an SF novel called Mathematicians in Love.

  How Gnarly Computation Ate My Brain

  I got my inspiration for universal automatism from two computer scientists: Edward Fredkin and Stephen Wolfram. In the 1980s Fredkin (see digitalphilosophy.org) began saying that the universe is a particular kind of computation called a cellular automaton (CA for short). The best-known CA is John Conway’s Game of Life, but there are lots of others. I myself have done research involving CAs, and have perpetrated two separate free software packages for viewing them.

  Wolfram is subtler than Fredkin; he doesn’t say that the universe is a cellular automaton. Wolfram feels that the most fundamental secret-of-the-life type computation should instead be something like a set of rules for building up a network of lines and dots. He’s optimistic about finding the ultimate rule; recently I was talking to him on the phone and he said he had a couple of candidates, and was trying to grasp what it might mean to say that the secret of the universe might be some particular rule with some particular rule number. Did someone say 42?

  I first met Wolfram at the Princeton Institute for Advanced Study in 1984; I was a freelancer writing an article about cellular automata destined for, as chance would have it, Isaac Asimov’s Science Fiction Magazine (April, 1987). You might say that Wolfram converted me on the spot. I moved to Silicon Valley, retooled , and became a computer science professor at San Jose State University (SJSU), also doing some work as a programmer for the computer graphics company Autodesk. I spent the last twenty years in the dark Satanic mills of Silicon Valley. Originally I thought I was coming here as a kind of literary l
ark—like an overbold William Blake manning a loom in Manchester. But eventually I went native on the story. It changed the way I think.

  For many years, Wolfram promised to publish a book on his ideas, and finally in 2002 he published his monumental A New Kind of Science, now readable in its entirety online. I like this book exceedingly; I think it’s the most important science book of our generation. At one point, my SJSU grad students and I even created a website for it.

  I’d been kind of waiting for Wolfram to write his book before I wrote my own book about the meaning of computation. So once he was done, I was ready to brush the lint of bytes and computer code off myself, step into the light, and tell the world what I learned among the machines. The result: The Lifebox, the Seashell, and the Soul (Thunder’s Mouth Press, 2005).

  Where did I get my book’s title? I invented the word “lifebox” some years ago to describe a hypothetical technological gizmo for preserving a human personality. In my book title, I’m using “Lifebox” as shorthand for the universal automatist thesis that everything, even human consciousness, is a computation.

  The antithesis is the fact that nobody is really going to think that a wised-up cell-phone is alive. We all feel we have something that’s not captured by any mechanical model—it’s what we commonly call the soul.

  My synthesis is that gnarly computation can breathe life and soul into a lifebox. The living mind has a churning quality, like the eddies in the wake of a rock in a stream—or like the turbulent patterns found in cellular automata. Unpredictable yet deterministic CAs can be found in nature, most famously in the patterns of the Wolfram-popularized South Pacific sea snail known as the textile cone. Thus the “seashell” of my book title. (You an search my blog for “cone shell” for information about these venomous mollusks.)

  Coming back to Wolfram’s A New Kind of Science, a lot of people seem to have copped an attitude about this book. Although it sold a couple of hundred thousand copies, many of the reviews were negative, and it’s my impression that people are not enthusiastically taking up his ideas. Given that I think these ideas are among the most important new intellectual breakthroughs of our time, I have to wonder about the resistance.

  I see three classes of reasons why scientists haven’t embraced universal automatism. (1) Dislike the messenger. Thanks to the success of his Mathematica software, Wolfram is a millionaire entrepreneur rather than a professor. Perhaps as a result, he has a hard-sell writing style, an iconoclastic attitude towards current scientific practice, and a sometimes cavalier attitude towards the niceties of sharing credit. (2) Dislike the form of the message. Some older scientists resent the expansion of computer science and the spread of computational technology. If you hate and fear computers, you don’t want to hear the world is made of computations! (3) Dislike the content of the message. Wolfram’s arguments lead to the conclusion that many real-world scientific questions are impossible to solve. Being something of a perennial enfant terrible, Wolfram is prone to putting this as bluntly as possible, in effect saying that traditional science is a blind alley, a waste of time. Even though he’s to some extent right, it’s hardly surprising that the mandarins of science aren’t welcoming him with open arms.

  One thing that sets my book off from Wolfram’s is the goal. At this point in my life, I don’t worry very much about convincing anyone of anything. To me the real purpose of writing a science book is to achieve personal enlightenment. And to get new ideas for science fiction novels.

  On the enlightenment front, The Lifebox, the Seashell, and the Soul ends with a discussion of six keys to happiness, drawn from considerations involving six successively higher levels of gnarly computation. And these will make a nice note upon which to end this article.

  Computer science. Turn off the machine. Nature computes better than any buzzing box.

  Physics. See the gnarl. The world is doing interesting things all the time. Keep an eye on the clouds, on water, and on the motions of plants in the wind.

  Biology. Pay attention to your body. It’s at least as smart as your brain. Listen to it, savor its complexities.

  Psychology. Release your thoughts from obsessive loops. Avoid repetition and go for the gnarl.

  Sociology. Open your heart. Others are complex as you. Each of us is performing much the same kind of computation. You’re not the center.

  Philosophy. Be amazed. The universe is an inexplicable miracle.

  * * *

  Note on “Adventures in Gnarly Computation”

  Written in 2005.

  Appeared in Isaac Asimov’s SF Magazine, October 2005.

  This short essay is adapted from The Lifebox, the Seashell, and the Soul: What Gnarly Computation Taught Me About Ultimate Reality, the Meaning of Life, and How To Be Happy. It’s always nice to publish a bit of science in Asimov’s, and my fellow SF writers seemed to enjoy the material.

  Web Mind

  The Web As a Model For the Mind

  My Web Mind column is meant to be a clear-channel broadcast of a mad scientist’s wild ideas. Like the good Dr. Frankenstein, one of my pet interests is the creation of life. For the first few columns I’m going to be talking about how (and why) you might go about making a computer copy of your mind.

  This summer I read a terrific book by Margaret Wertheim called The Pearly Gates of Cyberspace (W. W. Norton, 1999).

  She starts with this idea: the invention of pictorial perspective paved the way for Newtonian physics. This happened because perspective provides a tool for mapping unbounded three-dimensional space onto a finitely large two-dimensional canvas: the whole world in a square meter of cloth! Each object of the world gets assigned to one particular location upon the picture plane and, looking from the picture back out at the world, we can then see that the individual objects are contained in an all-encompassing world-space. Perspective teaches us to think of each object’s location as mapped into a mathematical (x, y, z) triple of coordinate numbers—and this is the space of mathematical physics.

  It’s fascinating to think that a new trick of artists made it possible to invent physics. Art matters! Accustomed as we are to seeing photographs, the perspective mapping of the world onto a square of paper seems obvious, even trivial, but it took people a long time to come up with it. And it was impossible for people to do modern physics until they had the idea of a unified underlying space. So, yes, maybe the invention of perspective really did lead to physics.

  Wertheim’s next step is the following: people used to have a notion of God as an entity that lived in physical space, but once Newtonian physics had made space into a Cartesian three-dimensional construct it seemed likely that God would have to live elsewhere. In the nineteenth century there was a feeling that God might live in the fourth dimension, but in post-Einsteinian physics has make all of the physical space dimensions into scientific constructs as well. Wertheim feels that we might now usefully ask ourselves if there is some tendency for present-day people to think of God as somehow located in cyberspace. Wertheim compares the science-fictional notion of making a software copy of oneself to the traditional religious notion of having a soul that goes to heaven, and suggests that if souls can be thought of as going into cyberspace, then perhaps some people might expect to find God in there as well.

  Let’s pause here to specify what is meant by the word “cyberspace.” One can usually think of “cyberspace” as simply a sexy word for “the Web” or “the Internet.” A little more generally, you can speak of cyberspace as a manifold containing all the kinds of data that one might conceivably access via a computer. My feeling is that cyberspace exists more as a container that holds data, rather than saying that cyberspace has an existence in and of itself. That is, I’d say that cyberspace is something like a pure, idealized, pre-quantum-mechanical vacuum: a content-free domain of positional possibility. But, just as it makes sense to inquire about the spatial dimensionality of an empty vacuum, it makes sense to talk about the dimensionality of cyberspace, and we’ll get into this que
stion below.

  Before getting to that, I’d like to make some remarks about the structure of cyberspace and of the human mind, to look for similarities between the two, and to speculate about future developments in philosophy and science. In the most concise possible form, the main idea I’m going to investigate here is the following.

  Web : Mind :: Perspective : Space.

  Might it be that the newborn Web provides a mapping tool which will lead to a mathematics of the human mind? As Marshall McCluhan taught, the effects of new media are wide-ranging and unpredictable.

  I have three reasons for thinking the Web is good for modeling the mind. First of all, the Web can display any type of media. Secondly, the Web has a hyperlinked structure reminiscent of mental associations. Thirdly, the Web and the mind’s pattern of links are mathematical fractals of a similar kind.

  Regarding the first point, the Web, a. k. a. cyberspace, is a network containing all the kinds of data that one might conceivably access via a computer. In and of itself, the Web is not limited to any particular form of media. It can dole out printed words, sounds, images, movies, or active programs. Just like the mind.

  The second point has to do with the fact that the Web pages by which we access Web data are written in hypertext (as in “Hypertext Markup Language,” a.k.a. HTML). One of the essential features of hypertext is that it contains hyperlinks: buttons you use to hyperjump to different locations in the hypertext. Later on, we’ll look at how this compares to the mind’s process of making associations.

 

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