Erik's Reviews > Permutation City

How do you define 'science fiction'?

From a quote from an interview with sci-fi author Ted Chiang:

“Sometimes, people who read my work tell me, ‘I like it, but it’s not really science fiction, is it?’” he says. “And I always feel like, no, actually, my work is exactly science fiction.” After Star Wars forever made the genre synonymous with what Chiang calls “adventure stories dressed up with lasers,” people forgot that science fiction includes the word “science” for a reason: It is supposed to be largely about exploring the boundaries of knowledge, he says. “All the things I do in my work — engaging in thought experiments, investigating philosophical questions — those are all things that science fiction does.”

Here’s one from an interview with Ray Bradbury:

Science fiction is the fiction of ideas. Ideas excite me, and as soon as I get excited, the adrenaline gets going and the next thing I know I’m borrowing energy from the ideas themselves. Science fiction is any idea that occurs in the head and doesn’t exist yet, but soon will, and will change everything for everybody, and nothing will ever be the same again. As soon as you have an idea that changes some small part of the world you are writing science fiction. It is always the art of the possible, never the impossible.

Using these as my definition of science fiction, I can say without qualification that Greg Egan is the greatest science fiction author I’ve ever read. I consider that an objective assessment. The ideas about which he writes are outstandingly imaginative, yet never seem impossible. That differential is why I consider him objectively the greatest. Because, sure, I've read science fiction with more outlandish ideas, and I've read science fiction that did a better job of convincing me of the possibility of its plot and setting. But I've never read (and I doubt such exists) science fiction with SUCH outlandish ideas that nevertheless still seemed possible. I'm tempted to say, "It's pure magic." But, well, it's not magic. It's science fiction.

Alas, as I wrote in Diaspora, Greg Egan is not for everyone. To truly appreciate what he’s accomplished in his writing, you need to be familiar with some physics and metaphysics. This is because Egan's books look at some theory or idea in physics and ask, "What does it mean?" His books attempt to pull back the Wizard's curtain and see what's there.

Here’s an example from classical physics: Newton’s law of gravitation is expressed with the equation F = G*m1*m2 / r^2 while Coulomb’s law (of electrostatics) is F = k*c1*c2 / r^2. Two fundamental forces (gravity and electromagnetism) that are otherwise quite different have such similar equations!

When I encountered this in my first physics class, it blew my mind. Surely such a coincidence suggests some underlying unity to the universe? If we think of physics as “the music of the celestial spheres” then such commonalities suggest there’s some invisible celestial composer, God or otherwise, giving it order. This explains in part why physicists are so hell-bent on creating a ‘unified theory of everything.’ Unity *feels* like truth.

However, the most interesting ideas – the ones that Greg Egan explores – arise from more modern physics, such as quantum mechanics and relativity. So let's talk about a theory that assuredly influenced Egan's writing of Permutation City: Quantum Electrodynamic's 'Sum-over-possibilities' approach.



Suppose I want to know whether some particle which starts at A will end up at point B and what path it will take. In classical physics, I can say yes or no depending on some relatively simple maths. But in quantum mechanics, at best I can tell you the probability of it happening. One of the ways I can calculate this probability is to look at ALL the possible ways A can get from B. There are infinite ways to do so, yeah? Mr. Electron can go straight from A to B. Or he can take make a pit-stop at the ice-cream-photon stand at point C to eat some mint chocolate chip photon-cream. Or he can take a little vacation 2.5 million light years away in Andromeda before going to point B. Now obviously that latter one is VERY out of the way, so it’s very unlikely so it doesn’t contribute much to my answer. BUT I DO NEED IT. Now with calculus (the math of infinities), we can do this calculation. Since particles (and even larger molecules) behave as waves, these various possible paths interfere with each other and parts of them cancel out. What remains is the actual path the particle ends up taking.

Which is just, wow, kinda awesome, yeah? Paths the particle COULD have taken – but didn’t – interfere with other such paths not-taken to arrive at the actual path??? WTF? For reals? Apparently.

When you realize this, when you realize these bizarre mathematical abstractions end up accurately predicting real world physical phenomenon, it doesn’t seem so outlandish to say, well, maybe there really are INFINITE other physical universes for all these other paths, including the one where our particle Mr. Electron really does travel to Andromeda, and maybe all these infinite universes influence each other in some way. Could there then be some meta-universe or at least some metaphysical rules that must be obeyed in these inter-universe interactions? What might this meta-universe be like then? What might those metaphysical rules be?

This is what Greg Egan does. He takes these metaphysical ideas and asks, “Okay suppose this were true. Suppose there really were infinite universes. How would people discover the truth? And what effect would that discovery have on them? And how do I write this so it sounds actually plausible?” That is a Greg Egan novel, in a nutshell.

And I can give you Permutation City in a nutshell too: it’s primarily about a man named Paul, who traps a Copy of himself in the virtual world in order to undertake some consciousness experiments. It asks the question, "Suppose every possible logically coherent permutation of reality actually did exist. How would someone find this out? And, finding it out, what would they do with this knowledge?" What follows is a compelling exploration of consciousness, religion, posthumanism, immortality, and, yes, the science and math behind some of these ideas.

That’s where we encounter a second problem in reading Greg Egan. The first problem, to summarize, is that if you don't know any higher-level physics or mathematics, you probably haven't done any of these metaphysical thought experiments yourself, so you're not gonna geek out as much that someone actually bothered to turn them into a story. The second is this: Greg Egan writes hard science fiction.

This isn't without reason. To people like myself and Egan, ideas aren’t compelling if they don’t have some basis in reality. Without such a basis, he might as well just write, “Yeah okay inside every electron, there’s a micro-universe in which talking unicorns poop rainbows at each other in an epic battle to reign as the supreme unicorn of the micro-universe, but it turns out these rainbows are actually the origin of conscious thought inside our brains. So really consciousness is the result of unicorns defecating rainbows.” Not really satisfying, huh? The math and science Greg Egan invokes in his writing are necessary language to communicate his ideas in a compelling manner. They are as necessary as the rules of English. If I write, “ef9uafojfk appleapple app le;;;; BANANA!” I’m not really communicating anything worthwhile am I?

But, again, that’s the genius of Greg Egan. He communicates ideas that could easily seem as outlandish and stupid and nonsensical as “appleapple app le;;;; BANANA!” but by bothering to give them a foundation in science & mathematics, he grants them an elegant verisimilitude. His stories seem real. And that which is real is usually more beautiful than that which is not.

All of this is not to suggest that Egan’s books are totally impenetrable without a PhD in Quantum Physics. While Egan is certainly unapologetic in his invocation of hard science & math, he ultimately keeps his focus on the humanity of his ideas. For example, in the world in Permutation City, there exist virtual ‘copies’ of sometimes dead (and sometimes still living) human beings. He shows the legal issues involved. Does a Copy have the same rights as an organic human being? There's several poignant interactions between one of the main characters and her mother, who is resistant to the idea of becoming an immortal Copy even when faced with her death. So, the humanity isn't lost in a swarm of technical details, as sometimes happens with science fiction.

In conclusion, if it isn’t clear, I think EVERY serious book-reader, especially every sci-fi reader, should at least attempt an Egan novel. If it turns out you can’t handle the hard science aspects, fine. Either go educate yourself on them (as I did when required in both Permutation City & Diaspora) or don’t and at least say you give it a fair shake.