I've always been interested in the connexion of philosophy and science fiction, two of my greatest passions. Much of science fiction (or at least much of it that's any good) is really philosophical speculation, for it postulates premises that challenge our common assumptions about ourselves and the world and then moves from there. Rob Sawyer, the Nebula-winning author of Hominids, even claims the genre should be renamed "phi-fi." So I was not really surprised to see that quite a lot of scholarly work has been published in this sense.
I bought two books for plane reading on my way home for the summer: "Science Fiction and Philosophy," a collection of essays and papers edited by U-Penn's Susan Schneider, and "Like a Splinter in Your Mind," edited by Matt Lawrence. The latter is not one of the infamous "~CRAPPY TV SHOW~ and Philosophy" titles, but an equally scholarly collection of sf-based philosophizing. A focus on The Matrix is only natural, after all, as it's among the deeper recent mainstream movies, at least conceptually.
I started with Schneider's anthology to get a broader feel for the subject, and that's what I'll be discussing here. I find this field rather promising and quite in-tune with my current research interests. The first section contains five articles about epistemology and skepticism in science-fiction, focusing on The Matrix. First, three excerpts introduce famous classical skeptical scenarios: Plato's cave, Descartes' methodological skepticism, and Hilary Putnam's brain-in-the-vat thought experiment. I suspect these were mostly included to grab the attention of those who haven't had formal training in philosophy, or perhaps as a refresher for those who have. Regardless, it's always pleasant to see editors include classic primary sources.
Then follows a supremely interesting article by Nick Bostrom. He defends the startling claim that not only should we take the "Matrix hypothesis" seriously, but it is actually more likely that we live in a simulated world rather than in a "real" one. This simulation argument goes like this: not all three of the following propositions can be true:
- Most civilizations die off before achieving technology to simulate sentient minds.
- Few civilizations have an interest (artistic, scientific, etc) in simulating minds.
- We almost certainly live in a simulation.
Now Bostrom contends that since the first two are likely to be false, (3) is likely to be true. Why would he think that? Because the first two ARE probably false. Contrary to (1), a civilization is unlikely to destroy itself before having developed mass-destruction technologies such as nuclear weapons, which makes it more likely that they will also achieve technologies capable of simulating minds. After all, Bostrom reminds us, even if WE currently can't simulate minds we are well on our way to being able to do so: the obstacles are mostly technological, not conceptual. Claim (2) is also false, assuming most civilizations share the intellectual and artistic curiosity of humans. More on this later.
However, the crux of the argument lies elsewhere. Let me rephrase it by turning those allegedly false premises into positive statements:
- There exist many civs with the technological means to produce simulated minds.
- Most of these civs are interested in producing simulated minds for scientific, artistic, or other purposes.
- * A civ thus technologically mature would be able to run huge numbers of simulated minds: once you have the technology and enough "hard disk space," so to speak, there is no limit to how many sim-minds you can create.
- Therefore, it is more likely than not that our minds are simulated.
Notice the paramount importance of premise (3*), previously unstated. In short, Bostrom claims we should expect to be sim-minds merely on a statistical basis. It reminds me of a witty anecdote (maybe by Richard Dawkins?) that since millions of religions have existed and there's no way to know for sure which one is "the true one," all believers should statistically expect to end up in Hell anyway, because chances are astronomically low that THEIR religion turns out to be the true one. Likewise, given the huge number of sim-minds a technologically advanced (and curious) civilization could run, no being in the universe has reason to believe he/she/it isn't one of those sim-minds.
What to say about the simulation argument? I find it fascinating but inconclusive. The first two premises sound like straw men at first, mere truisms (falsisms?) easily disproved, but even if so it doesn't matter too much, for the key premise is (3*). But the argument is still too simplistic. For one, it is very anthropocentric to think all civilizations will be so like ours that they too would take interest in simulating minds. (To this one might say, though, that a civilization with no scientific interest or intellectual curiosity would never achieve high technology to begin with). Even more importantly, the argument doesn't consider that the number of existing civilizations is also likely to be astronomically huge, which would counter the statistical basis on which the conclusion is drawn: it's true that each sim-mind-producing civ would be able to run billions and billions of sim-minds, but it's also true there are probably billions and billions of real minds to even the count. If so, then the argument has yet another problem: it may "prove too much," so much in fact as to be self-defeating. Assuming it works, then every rational being in the universe should accept it; but if they do, then there will be no being left who considers herself a "real" being--even those who actually are! The moral might be that a statistical inference is insufficient grounds for changing one's ontological view. The argument is promising and mind-bendingly attractive, but I don't find it compelling in its present form.
In the next essay, David Chalmers (with his trademark clarity of thought and exposition) recasts the Matrix hypothesis as a metaphysical hypothesis. He contends, in short, that The Matrix movie does not present a skeptical scenario akin to the brain in a vat or the Cartesian evil demon. Even if we do in fact live in a matrix, it simply does not matter to the reliability of our cognitive faculties (i.e., whether or not our thought processes function correctly). Why? Because all that we used to know about our (simulated) world still holds true even if we were to learn that there's another world beyond. We cannot say we are massively deluded: all we can say is that there was something about reality which we didn't know before, namely the fact that there's another world "one level up" from us. At most we can say that we may never know what the ultimate reality is and how many more "worlds-one-level-up" there are, but that's about it. So the Matrix hypothesis is but "a creation hypothesis for the information age" (says Chalmers), and thus it is a metaphysical and not at all a skeptical scenario. Still, since it does entail suspending judgment on the question of the ultimate nature of reality, I'm tempted to brand it "metaphysical skepticism," which is a little more than simple agnosticism and de facto a form of local skepticism.
Chalmers is hitting very close to (my) home here. Much of my recent research has focused on epistemic circularity and epistemic defeat. What Chalmers is saying, in effect, is that even if we came to believe we are sim-minds in a matrix, that new belief would not undercut other beliefs upon which we think our cognitive faculties are reliable. To borrow some terminology from Alvin Plantinga, it would be a truth defeater (for what we knew about the ultimate nature of the world was wrong) but not really a rationality defeater, for it wouldn't lead us to distrust our own cognitive faculties. While he is in the Matrix, Neo's cognitive faculties are perfectly functional: he thinks logically, he infers, he solves problems, he feels things, etc. When he leaves the Matrix, those faculties stay exactly the same and he has no reason to doubt they were EVER faulty. He has simply learned he was wrong about where the world comes from, but that doesn't imply that his *thinking* itself was ever faulty. An exception is if the machines running the Matrix were interfering with his brain to make him think things he wouldn't think by himself, such as altering his sense of logic or making him go insane. For example, for his first twenty years in the Matrix Neo is a Democrat, but then the machines change his mind to Republican and make him think he was *always* a Republican (and that would explain a LOT about our own world!). But this objection, while true, is valid whether or not we are sim-minds: we could say the same about an interventionist god, or an evil demon, etc. It's a genuinely skeptical objection, but it is not limited to the Matrix hypothesis and it is not enough to call the whole hypothesis a skeptical one.
The article by Chalmers made me recall that both Plantinga and Michael Bergmann had argued along similar lines while discussing Plantinga's evolutionary argument against naturalism. The Matrix example had sprung up in those papers, and both philosophers had regarded it as a truth defeater but not a rationality defeater. A truth defeater is a belief which, if you hold it, makes you lose confidence in another belief you also held. For example, I believe I have 50 cents in my pocket, but when I stick my hand in there I only feel one quarter; hence my newly-acquired belief "I have 25 cents" is a truth defeater for my previous belief "I have 50 cents." A rationality defeater, instead, is much more serious: if I acquire one, I will doubt my own cognitive faculties, my very thought processes. For example, I learn that I've ingested a pill that makes people hallucinate and then go totally insane. Rationally, I'd have to assume that perhaps I am already under the pill's influence; maybe I didn't really take the pill after all, but the mere suspicion that I might have is enough to make me lose confidence in my own mind and will soon tear me apart. With this in mind, back to Chalmers now. Even though he doesn't frame his discussion in terms of epistemic defeat, that is in fact what he is saying: the Matrix scenario is a truth defeater but not a rationality defeater. He then applies the same reasoning to other so-called skeptical scenarios such as Bertand Russell's five-minute hypothesis and Putnam's own brain-in-a-vat experiment. These simply aren't skeptical scenarios at all: they're metaphysical problems. In this case, philosophy and common sense do get well with each other, because the conclusion is that even if we live in a matrix (or our brains are envatted, or the universe was created five minutes ago, etc) it really doesn't matter for our present purposes. Even after we learn the truth, we will be the same people as we were before and we would have no reason to believe we were being otherwise deluded.
I'll end with two questions that have nagged me throughout the reading. One concerns Berkeley's idealism, of course: are things there when we can't perceive them? To what extent is the real actually "there" if we don't see all of it at the same time? If we live in a matrix and our world is only in our minds, can we say that we perceive it all and it is thus perfectly real to us even if it is simulated? Chalmers certainly seems to think so. (Of course, one needn't speculate about matrices to appreciate the beauty of Berekeley's idea, revamped as it is by modern-day worries on quantum uncertainty). The other question, closely related, is about scientific realism, viz. the idea that what science describes is the "stuff" that's out there. How does the Matrix hypothesis--in either Bostrom's probability argument or in Chalmers' metaphysical recast--affect scientific realism? If we are in a matrix, to what extent can we say that what our science describes is really there at all? Is the fact that we're perceiving it enough to say it's there?
Sounds awfully Berkeleyan to me....... but then again, most things do!
Readings/references:
- "Science Fiction and Philosophy" (Wiley-Blackwell 2009, ed. Susan Schneider)
- David Chalmers, "The Matrix as a Metaphysical Hypothesis," 2002.
- Nick Bostrom, "Are You in a Computer Simulation?" 2003.
- Michael Bergmann, "Commonsense Naturalism," in Naturalism Defeated?, 2002.
- Alvin Plantinga, "Reply to Beilby's Cohorts," in Naturalism Defeated?, 2002.
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