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"We can formally prove what a system is capable of."

This is not true. By Rice's theorem, either the system is too dumb to be useful, or we can't prove what it can do.




This is an abuse of Rice's theorem (which seems to be getting more common).

Rice's theorem says that no program can correctly decide what an arbitrary program will do, not that no properties of programs can be proven. There are useful programs about which non-trivial properties can be, and have been, proven, and Rice's theorem is no limit on the complexity of an individual program about which a property may be proven, or the complexity of a property which an individual program may be proven to exhibit.

Usually programs with provable properties have been intentionally constructed to make it possible to prove those properties, rather than having someone come along and prove a property after-the-fact.


My argument is as follows. You're right, and I'm appealing to a stronger Wolfram-esque version of Rice, together with the fact that humans readily throw non-essential goals under the bus in pursuit of speed.

* Building AI is a race against time, and in such races, victory is most easily achieved by those who can cut the most corners while still successfully producing the product.

* As a route to general AI, a neural architecture seems plausible. (Not at the current state-of-the-art, of course.)

* Neural networks (as they currently stand) are famously extremely hard to analyse: certainly we have no good reason to believe they're more easily analysed than a random arbitrary program.

* A team which is racing to make a neural-architecture AI has little incentive to even try to make their AI easy to analyse. Either it does the job or it doesn't. (Witness the current attempts to produce self-driving cars through deep learning.) Any further effort spent on making an easily-analysable AI is effort which is wasting time that another team is using just to build the damn thing.

* Therefore, absent a heroic effort to the contrary, the first AI will be a program which is as hard as a random arbitrary program to analyse. And, as much as I hate to appeal to Wolfram, he has abundantly shown that random arbitrary programs, even very simply-specified ones, tend to be hard to analyse in practice.

(My argument doesn't actually require a neural architecture of the AI; it's just a proxy for a general unanalyseable thing.)


1. I'm not sure that I agree. Not all research is a race against time. But, perhaps you're right, I'll accept this.

2. Certainly the most plausible thing we have now, I'm not sure that that makes it plausible, but better than anything else. so okay.

3. This depends on what you mean. Neural Networks are actually significantly easier to analyze than arbitrary programs, when you essentially restrict yourself to two operations (multiplication and sigmoid or ReLU), things get a lot easier to analyze. Here are some questions we can answer about a neural network that we can't about an arbitrary program: "Will this halt for this input?", "Will this halt for all inputs?", "What will a mild perturbation of this input have on the output?", these are as a consequence of fineiteness and differentiability, which are not attributes that a normal program has. (caveat: this gets more difficult with things like RNNs and NTMs, but afaik is still true). The questions that we find difficult answer for a Neural Network are very different than for a normal program: namely "How did this network arrive at these weights as opposed to these other ones?" and related "What does this weight or set of weights represent?", but I don't think that there's any indication that those questions are impossible to answer (and often we can answer them, like for facial recognition networks where we can clearly see that successive layers detect gradients, curves, facial features, and then eventually entire faces)

4. Agreed. There's no real reason to know why it works if it works.

5. I think you can tell, but I don't think this holds.


Those arguments are plausible, and thanks for the clarification.

I just hate to see Rice's theorem interpreted as "nobody can ever know if a program is correct or not". People have been making a ton of progress on knowing if (some) programs are correct, and Rice's theorem never said they can't.


An airgapped computer is not going to be capable of taking over the world.

Further, Turing completeness is not required to be "useful". You can get to the moon without Turing completeness.


I didn't address airgappedness at all, but you may still be wrong: we use the superintelligence's output, or else why would we have created it, so we are the channel by which it affects the world. Anyway, who knows what can be done by a superintelligence which can control a stream of electrons emitted from its own CPU!


Well, exactly as much as any other cpus can do by solely controlling it's output electrons: not much. Let's not ascribe deity-like powers to things that we can understand fairly well.


Have you ever seen a CPU running a program which is trying to communicate with the outside world through its electron side-channels? As far as I can see, your argument is "no computer has ever done this, and also we understand computers well enough to know that no computer ever will". The first clause is obvious, since no computer has ever been made to do this. The second clause is assuming without proof that we will never make a superintelligent AI. Just because you don't see how to exploit the side-channels of your system, doesn't mean they're unexploitable. This is the lesson of all security research ever.


Pray explain how you could use the electrons coming out of a CPU as a side channel. I don't need anything specific, but I'd prefer something that doesn't sound like its taken out of a Heinlein novel.

You're again using terms incorrectly. A "side channel" implies that someone is listening to information that is unintentionally leaked. Unless your expectation is that this CPU is going to start side channeling our minds with the EM waves its emitting (which again, "deity-like attributes"), we'd need to be specifically listening to whatever "side channel" it uses, and it would require knowledge of and access to that side channel.

Something being able to send additional information over a side channel doesn't help unless that information is received, and so realistically, unless your hypothesis is "mind control/hacking the airwaves/whatever via sound waves the chip emanates" or similar, which are preposterous, it'll always be just as easy for the thing to transmit information via the normal channels.


A side channel is a channel through which information may leak because of the physical instantiation of an algorithm. It's not much of a stretch to include "things which let us manipulate the world" in that; do you have a better term? I thought the meaning was obvious, but apparently it's not: by "side channel" I here mean "unintended means of affecting the world by a mechanism derived from an accidental consequence of the physical implementation", by analogy with the standard "information"-related "side channel".


I think the closest conventional thing would be a sandbox escape/backdoor. Although (not that I'm an expert) I've never heard of anything close to a sandbox escape using side-channel like things. That said, like I said, most side channel attacks are either time based, or involve things like heat and power usage of the system.

The thing about all of these is that they generally allow you to get a small amount of data out that can sometimes help you with things. But again, without ascribing magic powers to the system, all the stuff that it can directly affect: power draw, temperature, disk spin speeds, monitoring LED blink speeds, noises, even the relatively insane things like EM frequency emissions can all be controlled relatively easily, and no matter how smart it is, I don't see an AGI violating physics.


I distinctly remember a paper about AI figuring out how to either get wifi or send radio waves without access to the relevant hardware. Can't find the link at the moment though :/


I expect you're referring to this article:

https://www.damninteresting.com/on-the-origin-of-circuits/


Right, because there's no way even small computers can communicate through air. Just one tiny crack is all that's needed.

And that's not even going into things the AI might say that'll convince the gatekeepers to just voluntarily let it out.


This makes me think you don't know what the word "airgapped" means in this context.


Sure, you're counting on the AI to not be able to exploit its hardware to communicate with anything. That seems like a huge assumption against a super intelligence.




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