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Gnarly SF Reality. #1: What Is Gnarl?

This post and the next one are drawn from an essay called “Gnarly SF” which appears in my Collected Essays. You can read the complete essay online as part of the Collected Essays, but I decided to extract two blog posts from it. Also note that the essay appears in my small collection Surfing the Gnarl, 2012, brought out by the estimable PM Press of Oakland, California.

I’m going to split my excerpts into two pieces: “What is Gnarl?” in today’s post, and “Change the World,” which will be in my next post.

The illos are drawn from my backlog of photos. As is customary in my blogs, the only thing linking the images to the text is the Surrealist principle of juxtaposition.

I use gnarl in an idiosyncratic and somewhat technical sense; I use it to mean a level of complexity that lies in the zone between predictability and randomness.

The original meaning of “gnarl” was simply “a knot in the wood of a tree.” In California surfer slang, “gnarly” came to describe complicated, rapidly changing surf conditions. And then, by extension, something gnarly came to be anything with surprisingly intricate detail. As a late-arriving and perhaps over-assimilated Californian, I get a kick out of the word.

Do note that “gnarly” can also mean “disgusting.” Soon after I moved to California in 1986, I was at an art festival where a caterer was roasting a huge whole pig on a spit above a gas-fired grill the size of a car. Two teen-age boys walked by and looked silently at the pig. Finally one of them observed, “Gnarly, dude.” In the same vein, my son has been heard to say, “Never ever eat anything gnarly.” And having your body become old and gnarled isn’t necessarily a pleasant thing. But here I only want to talk about gnarl in a good kind of way.

Clouds, fire, and water are gnarly in the sense of being beautifully intricate, with purposeful-looking but not quite comprehensible patterns. And of course all living things are gnarly, in that they inevitably do things that are much more complex than one might have expected. As I mentioned, the shapes of tree branches are the standard example of gnarl. The life cycle of a jellyfish is way gnarly. The wild three-dimensional paths that a humming-bird sweeps out are kind of gnarly too, and, if the truth be told, your ears are gnarly as well.

I’m a writer first and foremost, but for much of my life I had a day-job as a professor, first in mathematics and then in computer science. Although I’m back to being a freelance writer now, I spent twenty years in the dark Satanic mills of Silicon Valley. Originally I thought I was going there as a kind of literary lark——like an overbold William Blake manning a loom in Manchester. But eventually I went native on the story. It changed the way I think. I drank the Kool-Aid.

I derived my notion of gnarl from the work of the computer scientist Stephen Wolfram. I first met him in 1984, interviewing him for a science article I was writing. He made a big impression on me, and introduced me to the dynamic graphical computations known as cellular automata, or CAs for short. The so-called Game of Life is the best-known CA. You start with a few lit-up pixels on a computer screen. Each pixel “looks” at the eight nearest pixels, counts how many are “on” and adjusts its state according to this total, using a fixed rule. All of the pixels do this at once, so the screen behaves like a parallel computation. The patterns of dots grow, reproduce, and/or die, sometimes generating persistent moving patterns known as gliders. I became fascinated by CAs, and it’s thanks in part to Wolfram that I switched from teaching math to teaching computer science.

Wolfram summarized his ideas in his illuminating 2002 tome, A New Kind of Science. To me, having known Wolfram for many years by then, the ideas in the book seemed obviously true. I went on to write my own tome, The Lifebox, the Seashell, and the Soul, partly to popularize Wolfram’s ideas, and partly to expatiate upon my own notions of the meaning of computation. A work of early geek philosophy. Most scientists found the new ideas to be—as Wolfram sarcastically put it—either trivial or wrong. When a set of ideas provokes such resistance, it’s a sign of an impending paradigm shift.

So what does Wolfram say?

He starts by arguing that we can think of any natural process as a computation, that is, you can see anything as a deterministic procedure that works out the consequences of some initial conditions. Instead of viewing the world as made of atoms or of curved space or of natural laws, we can try viewing it as made of computations. Keep in mind that a “computer” doesn’t have to be made of wires and silicon chips in a box. It can be any real-world phenomenon you like. Does this make the world dull? Far from it.

Having studied a very large number of visually interesting computations called cellular automata, Wolfram concluded that there are basically three kinds of computations and three corresponding kinds of natural processes.

Predictable. Processes that are ultimately without surprise. This may be because they eventually die out and become constant, or because they’re repetitive. Think of a checkerboard, or a clock, or a fire that burns down to dead ashes.

Gnarly. Processes that are structured in interesting ways but are nonetheless unpredictable. Here we think of a vine, or a waterfall, or the startling yet computable digits of pi, or the flow of your thoughts.

Random. Processes that are completely messy and unstructured. Think of the molecules eternally bouncing off each other in air, or the cosmic rays from outer space.

The gnarly middle zone is where it’s at. Essentially all of the interesting patterns in physics and biology are gnarly. Gnarly processes hold out the lure of being partially understandable, but they resist falling into dull predictability.

Anything involving fluids can be a rich source of gnarl—even a cup of tea. The most orderly state of a liquid is, of course, for it to be standing still. If one lets water run rather slowly down a channel, the water moves smoothly, with a predictable pattern of ripples.

As more water is put into a channel, the ripples begin to crisscross and waver. Eddies and whirlpools appear—and with turbulent flow we have the birth of gnarl.

Once a massive amount of water is poured down the channel, we get a less interesting random-seeming state in which the water is seething.

Now, the pay-off for this whole ine of thought is that it becomes possible, via some computer-science legerdemain, to argue that all of the interesting processes of nature are inherently unpredictable.

What, by the way, do I mean by “predicting a process”? This means to have some procedure for determining the processes result very much faster than the time it takes to simply let the process run. Saying that a gnarly process is unpredictable, means there are no quick short-cut methods for finding out what the process will do. The only way to really find out what the weather is going to be like tomorrow is to wait twenty-four hours and see. The only way for me to find out what I’m going to put into the final paragraph of a book is to finish writing the book.

It’s worth repeating this point. We will never find any magical tiny theory that allows us to make quick pencil-and-paper calculations about the future. Sometimes scientists—or science-fiction writers—have speculated that there’s some compact master-formula capable of predicting the future with a few strokes of a pencil. And many still have an internal faith in some slightly more sophisticated restatement of this.

But we have no hope of control. On the plus side, the gnarly is a bit better behaved than the fully random. We can’t predict the waves, but we can hope to ride them.

As a reader, I’ve always sought the gnarl, that is, I like to find odd, interesting, unpredictable kinds of books, possibly with outré or transgressive themes. My favorites would include Jack Kerouac and William Burroughs, Robert Sheckley and Phil Dick, Jorge-Luis Borges and Thomas Pynchon.

Once again, a gnarly process is complex and unpredictable without being random. If a story hews to some very familiar pattern, it feels stale. But if absolutely anything can happen, a story becomes as unengaging as someone else’s dream. The gnarly zone lies at the interface between logic and fantasy.

William Burroughs was an ascended master of the gnarl. He believed in having his work take on an autonomous life to the point of becoming a world that the author inhabits. “The writer has been there or he can’t write about it… [Writers] are trying to create a universe in which they have lived or where they would like to live. To write it, they must go there and submit to conditions that they might not have bargained for.” (From “Remembering Jack Kerouac” in The Adding Machine: Selected Essays, Seaver Books 1986.)…

In order to present some ideas about how gnarl applies to literature in general, and to science-fiction in particular, I’m going to make up four tables to summarize ho gnarliness makes its way into science-fiction in four areas: subject matter, plot, scientific speculation, and social commentary.

In drawing up my tables, I found it useful to distinguish between low gnarl and high gnarl. Low gnarl is close to being periodic and predictable, while high gnarl is closer to being fully random.

Keep in mind that I’m not saying any particular row of the table is absolutely better than the others. My purpose here is taxonomic rather than prescriptive. Rather than using the words “predictable” and “random” to refer to the lowest and highest levels of complexity, one might use the less judgmental words “classic” and “surreal.”

Just so you have a general idea of what I’m talking about, here’s how I see some of my favorite authors as located on the complexity spectrum:

Complexity Level  Sample Authors
 Classic Golden Age F&SF.  J.R.R. Tolkein, Isaac Asimov, Kage Baker.
 Lower Gnarl  Robert Heinlein, William Gibson, Bruce Sterling, Cory Doctorow, Karen Joy Fowler.
 Higher Gnarl  Charles Stross, Robert Sheckley, Phillip K. Dick, Eileen Gunn, me.
Surreal  Douglas Adams, John Shirley, Terry Bisson, Anna Tambour.

Let me stress again that I admire the work of all the authors in this table. The point here is simply to point out that one can use various modes and approaches to writing SF. Note that some authors may write novels in various modes—Terry Bisson’s Pirates of the Universe for instance, is high gnarl and transreal, rather than random and surreal.

7 Responses to “Gnarly SF Reality. #1: What Is Gnarl?”

  1. Miramon Says:

    I think “gnarl” is a nifty way of characterizing literature, SF in particular. Just as automata can be dull because they’re too stable or dull because they’re too random, there is a sweet spot for literature that is unpredictable without being completely irrational or totally disjointed. Order out chaos and chaos out of order, as it were. But just as you point out, the analogy isn’t perfect, because both “classic” and “surreal” fiction can be very good, too. So gnarl is an interesting literary dimension, but it’s not a definite indicator of quality.

    —- digression —-

    You mentioned Wolfram in this piece. This moves me to wonder about your opinion of A New Kind of Science.

    Frankly I was very disappointed in this book, knowing of the man’s previous accomplishments. Not only did the theses seem dull to me — philosophically naive in some cases — but the supporting material was weak too, IMO. I was also surprised by the lack of references to other people’s work (including yours) in a supposedly scientific volume. The bulk of this particular book just fell flat for me, especially as it was written with a sort of self-satisfied arrogance I found hard to take, considering the book presented no concrete or useful results that I could see.

    So what do you think? Did he do good work here that I (not an expert in the field) have overlooked? Has anything useful come out of this work, now that it’s 10 years later?

    I understand this is a digression not very well related to your post, and morever Wolfram is a friend of yours — I’ve never met him, but I acknowledge his many other accomplishments — so feel free to ignore or delete this comment. But I’ve tripped over your blog, having always admired your writing, and the mention of the man’s name made me curious what you thought of this work.

  2. Rudy Says:

    Miramon, thanks for the intelligent comments.

    I did like A NEW KIND OF SCIENCE very much—it wouldn’t be too much to say that the ideas therein have completely changed the way that I look at the world.

    I’m well aware of the stylistic idiosyncracies of NKS that you mention. These kinds of things are not at all rare in the history of science, and I feel one can overlook them, and simply enjoy the ideas.

    I know the book got some bad reviews, but in my opinion those reviewers didn’t fully grasp (or weren’t willing to appreciate) the book’s really quite revolutionary content. As Wolfram once put it in conversation, “Half of them say it’s trivial, and half of them say it’s wrong. I think that’s a good place to be.”

    I wrote a long and positive review of NKS in the Reviews section of the Mathematical Association of America Monthly, November, 2003, see the link below.

  3. Mike Gambone Says:

    I’ve been a friend since the Dark Days and a fan ever since. This is also off the subject of gnarl, and the reason I’m claiming a sort of special knowledge of you and your work (after all, I was a Dead Pig) is that I’m compelled to say something about things that are included in this and every blog but not usually even indirectly addressed. You describe yourself as a writer and teacher and painter (and though you talk about cameras and lenses and such, you make no similar claims about your talent thereabout), and not to take anything away from the manifestations of those other talents, what really rocks is your photography; your composition and choice of subject. Day after day.
    Maybe it is gnarl, in the best sense.

  4. Justin Patrick Moore Says:


    I picked up your gnarly book The Secret of Life in a used bookstore recently. I’ve been digging it, and can’t wait to compare my notes on it with the Big Aha, seeing how you will deal with some of the similar themes in your new novel.

  5. Rudy Says:

    Mike, thanks for checking in. Yes, I do think a lot about my photography, and I’m glad you appreciate it. I don’t bother pushing it as a real “career” of mine as it’s already so much work trying to be a writer and, to some extent, a painter.

    One of the reasons I run this blog is in fact so I can put my photos out there—once I carefully shoot them and tweak them in Lightroom, I do want them to be seen. As you sense, there are some posts where the text is more like a pretext for the PHOTOS. Today’s batch is a good one, as they range over the last two years, and have survived numerous winnowings of the stash.

    By the way I also post many of my photos as a stream on Flickr, updating the stream in bulk once every couple of months. There’s not an exact match with the photos I blog, but it’s close. The Flickr interface is a lot nicer than it used to be. And you can see the photos in Flickr in much higher rez.

    It’s always good to recall my (frequently) happy times together with you back in Killeville, VA, Mike. Grinning nihilists that we were…

  6. Rudy Says:

    Justin, I’m glad you got hold of THE SECRET OF LIFE. I plan to reissue it fairly soon as an ebook and paperback, probably bound together with a related memoir called ALL THE VISIONS.

  7. A. Kartturi Says:

    Julio Cortazar (from Argentina also, one of the best short story writers), Sadeq Hedayat (from Iran, read his “The Blind Owl”), many Russian writers.
    Also, read R. C. Zaehner’s “ideological book” “Our Savage God”, even if you don’t like his views.

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