Any sufficiently advanced technology is indistinguishable from magic.
— Sir Arthur C. Clarke (1917 – 2008)
The above quote is quite famous, at least amongst certain types of people. And the core idea is a pretty idealistic and hopeful one: technology will one day get so advanced that it will look like magic.
Or maybe it’s actually quite realistic, under another lens. If you brought a peasant from the Middle Ages to the present and showed them fast-moving gigantic flying metal contraptions, thin screens that show people on the other side of the world, and little gadgets that let you scry the past and communicate with your loved ones no matter where they are, the peasant would run away screeching: “WITCHCRAFT!” They wouldn’t run very far, they’d probably be hit by a car, but they’d run alright.
Sufficiently analysed magic is indistinguishable from science (warning: TV Tropes link). This sentence is similar to the quote starting the post, but it’s not nearly as deep or meaningful. Science is, after all, just the method. If a thing exists, then it falls under the scope of science. So if magic exists and works then it can be science’d. Let’s try to science it. Exactly how magical does magic have to be before it goes beyond the boundaries of what’s achievable by technology? Exactly how advanced does technology have to be before it’s far enough from our suspension of disbelief that we’re willing to call it magic?
A more practical question might be: what should you conclude about the universe once you observe magic in it?
In The Finale, one of the characters mentions two kinds of universes: natural universes, and magical universes.
The former are those that are describable by mathematically simple, exceptionless low-level laws. Our own universe looks like it works that way, though we don’t know yet what the true laws are. We know quite a bit about it, given that the places the boundaries of current physics are at are the subnanometric scale or the cosmological one. We have a feeling that the laws are in fact unifiable into one simple framework, though even if that’s not the case it still looks like the world is, at its core, maths.
Magical universes, on the other hand, are those whose rules aren’t like that. They’re universes that are complicated, full of exceptions for high-level phenomena, particularly minds. Whenever you find minds that are irreducibly complex and that physics bends this way or that to satisfy their whims, you have one of those universes. Most major religions believe we live in a magical universe, what with souls and miracles and stuff like that.
And this division is in fact natural and clear-cut: either the laws are universal, or they’re not. If there’s some law that applies in certain domains but not in others, then we’re in a magical universe. As soon as there’s a single exception, then that’s a magical universe. Of course, it might be a fairly boring magical universe, one where the speed of light in a vacuum is exactly c everywhere except within a three-meter sphere radius about five light-years from the Sun where it’s actually 0.9943c instead. In fact, for all we know we’re living in such a magical universe. So then maybe we could make these definitions more flexible to allow for a continuous gradation of magic, with more or less magical universes depending on how big the exceptions are.
At any rate, Clarke’s third law still applies: most appearance of magic can still be created by technology. Light travels slower in means other than a vacuum, so maybe we could use nanotechnology to create that sphere in such a way that it looks like a vacuum, but there’s in fact material there that makes light travel slightly slower. If you want a more complete example of exactly how far technology can simulate magic, I have a piece of fiction to offer you. However, it’s very spoilerish of me to tell you what piece of fiction it is, because it’s not apparent from the start that that universe’s magic is brought by technology, so I’m going to leave a link, and if you don’t want to know what it is, just don’t click it or mouse over it. It’s this one.
So, let’s see. Conjuration? Sure, nanotechnology. Flight? Easy peasy. Souls? People coming back from the dead? No problemo. Teleportation? Piece of cake. Violating the laws of thermodynamics? Well, as long as you think you’re violating them…
Is there any magic that can’t be created directly by technology?
Time Magic and Harry Potter
How would you go about going back in time? How would you go about making precise prophecies of the future? How would you deal with Time-Turners?
Suppose at time you heard a prophecy about something that would happen at time . Then ‘s state depends on ‘s state and on ‘s. Then ‘s state depends on ‘s state, but that one depends on ‘s and ‘s, which means ‘s state depends on itself, and we get a causal loop. How would you go about simulating this in a straightforward step-by-step way?
You wouldn’t. You might suggest that you could simulate it many times until the timeline converged to one where the loop was stable, but as anyone who has studied analysis can tell you, there is no guarantee of convergence after repeated application of a function many times, so this simulation may very well simply never converge.
Or suppose, for example, that I took a time-turner and made a decision: if in five minutes I don’t see a time-turned version of myself, then an hour after that I’m going to time-turn myself; if I do see me, then I won’t. How would that paradox resolve itself? There is no stable time loop that contains this.
And the answer is that… well, here’s a barrier technology can’t cross easily. You can’t in fact step-by-step compute a time-turner. The reason time-turners work is because Rowling knew what was going to happen in the future, so she structured the entire timeline to include that.
So, the way technology would have to create time-turners would be by… mind-controlling everyone involving, and reality, too. There’s no way around it, really. There’s no way, without knowledge of what you want the future to contain, to include “free will” (in the sense that only agents within the system can influence the system) and stable time loops. The way you’d simulate a universe with stable time loops would be simulating all possible universes given the starting conditions, then deleting all of those that don’t contain stable time loops and keeping only the ones that do. In fact, stable time loops can be used to solve the P vs. NP problem. In fact, stable time loops are completely impossible under quantum mechanics, in the sense that they’d disprove Q.M. if they were discovered.
I mentioned, in my post about Occam’s Razor, that the best mathematical formalisation of the Razor we’ve been able to find was Solomonoff Induction, which penalises hypotheses based on their description length. So if that’s the case…
…then magical universes can more-or-less be ruled out a priori. Not the boring kind, but the kind of magical universes most religions believe we live in, where minds are ontologically basic and capable of breaking and twisting the laws of physics. Deities, souls, if taken at face-value, are possible in some worlds, but those worlds are so vastly more complicated than ours that the probability of finding ourselves in them is completely negligible.
I mean, you’d need a program that defines our entire world, and then it also had an exception clause that described an entire human brain and said “that thing has a soul” or “whenever that thing wishes something/prays/whatever, reality’s laws change.” It’s possible, but enormously unlikely.
But unlike stable time loops, most other magic is actually feasible in our universe, via technology. So if we find magic, we should still conclude technology. If we find stable time loops… maybe the world doesn’t behave as nicely as we’d previously thought.
Okay, so… what does it mean, then, to find yourself in a magical universe? What do you conclude?
Maybe my phrasing was misleading when calling a magical universe “magical.” Obviously all laws are necessarily mathematical in some sense, since mathematics is… well, everything. Literally everything can be described by mathematics.
But a magical universe?
What kind of universe has exceptions for minds?
What kind of mechanism can systematically create things that are really unlikely by sheer accident?
What kind of force consistently beats formulating the absolutely simplest solutions, and can in fact search the solution space for something with very low probability that satisfies certain constraints?
Intelligence, of course.
Magical universes, if they exist, will probably be in their vast majority embedded in natural ones. Computer simulations, artificial environments created by an intelligence that inhabits a natural universe. Beating Solomonoff Induction, creating an exceedingly unlikely possible world so that conscious observers can find themselves special?
Magical universes are artificial. Magical universes, universes whose laws have exceptions… they’re, well, not natural. That’s why the other kind of universe is called Natural Universe. Because a magical one is, almost without a doubt, artificial, too.
So, sufficiently advanced technology is indistinguishable from magic. And magic is, all the time, sufficiently advanced technology. All magic is, necessarily, artificial.