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Logical Induction

intelligence.org

41–50 of 66 posts

Re: Logical Induction

#41
post #33

So does this mean that the era of automated theorem proving and AI-driven mathematics is finally upon us? I'm no expert, but this seems pretty groundbreaking.

This is MIRI; they do really interesting theoretical philosophy and worryingly small amounts of practical research.

At least public practical research. But I've long wondered what their bank account would look like if they had a side venture into exploiting narrow AI for commercial use rather than rely on donations.

Re: Logical Induction

#42

Earlier quoted context omitted.

How do you manage to claim that your computable logical inductor dominates the incomputable universal semimeasure?

I'm not an author but this property with respect to a universal 'semimeasure' holds in the limit as time goes to infinity, as do most stated properties of logical inductors. The fact that they're computable is academic.

This is right, but perhaps misleading; most of the properties are "asymptotic", meaning that they may take an extremely long time to hold, but they hold at finite times. For example, "provability induction" says that if you have a (polytime computable) sequence of sentences phi_n, all of which happen to be provable (possibly with fast-growing proof lengths), then P_n(phi_n) limits to 1. This means that on day n the logical inductor P is confident of phi_n, even though phi_n may take much longer than n steps to prove.

Re: Logical Induction

#43
post #39
post #33

Earlier quoted context omitted.

This is MIRI; they do really interesting theoretical philosophy and worryingly small amounts of practical research.

What is your definition of practical?

My concept of practical is stuff like: implementing things, doing experiments with prototypes, producing stuff that is imperfect but does something and can be improved upon.

Theoretical stuff is like: proving theorems, conceptualizing the task at hand, philosophical inquiry into the nature of agents/intelligence/reasoning/goals/human values

I'm not trying to argue which is more important, but surely MIRI focuses more on the theoretical.

Re: Logical Induction

#44

The article is basic mathematical research and is not intended to be implemented, but rather to guide further applied research. The deeper motivation for this article is to allow future Artificial General Intelligences to prove facts about themselves; specifically, the fact that the AGI, or a next-gen that it developers, has the same (safe) utility function that the designers originally specified. A formal system can…

"fear not humans, I am probably going to comply with Asimov's first law"

Re: Logical Induction

#45
post #37

The article is basic mathematical research and is not intended to be implemented, but rather to guide further applied research. The deeper motivation for this article is to allow future Artificial General Intelligences to prove facts about themselves; specifically, the fact that the AGI, or a next-gen that it developers, has the same (safe) utility function that the designers originally specified. A formal system can…

> A formal system cannot in general prove that it is reliable, i.e. that if it proves statement P then P is true. I'm not entirely sure what you mean by this (I haven't read the article yet, and I'm already familiar with Loeb's theorem). It's true that you cannot show that, say, second order arithmetic is consistent in the same system. In fact, every soundness proof (for a sufficiently strong logic) will have to be c…

The expressiveness of the tower of universes limits to that of Peano arithmetic, correct? Otherwise, there would exist a universe k that contain theorems that could not be computably proven in universe k+1.

On a separate matter, are there any principled meta-universal rules for incrementing the universe index? That is, if one suspects that one's current universe lacks proving power, is it possible to generate the axioms for a more powerful universe?

Re: Logical Induction

#46
post #41
post #33

Earlier quoted context omitted.

This is MIRI; they do really interesting theoretical philosophy and worryingly small amounts of practical research.

At least public practical research. But I've long wondered what their bank account would look like if they had a side venture into exploiting narrow AI for commercial use rather than rely on donations.

Maybe they have a problem attracting those types of researchers for some reason.

Re: Logical Induction

#47
post #14

Slightly OT but it's well worth watching the recent film about Ramanujan, "The Man Who Knew Infinity". It has kept me thinking what "intuition" really is, how it develops and happens in the brain, and what would be needed to build AI that has intuition.

Douglas R. Hofstadter has written multiple books on the subject. He most directly addresses it in "Surfaces and Essences" co-written by Emmanuel Sander.

It is enjoyable reading and very thorough. Pending revolutionary new insights I might even regard it as conclusive.

Re: Logical Induction

#48
post #39
post #33

Earlier quoted context omitted.

This is MIRI; they do really interesting theoretical philosophy and worryingly small amounts of practical research.

What is your definition of practical?

MIRI is entirely Blue Team - they work to create theoretical [0] safeguards on AI agents yet to be developed. I've long envisioned a counterpart Red Team that does nothing but build AIs that attempt to subvert these safety features, since the rest of the world of non Friendly AI [1] research is only unco-ordinated para-red behavior.

[0] In the sense of "valid under these known precepts", not "speculative".

[1] Non "Friendly AI", not "non-Friendly" AI.

Re: Logical Induction

#49

The article is basic mathematical research and is not intended to be implemented, but rather to guide further applied research. The deeper motivation for this article is to allow future Artificial General Intelligences to prove facts about themselves; specifically, the fact that the AGI, or a next-gen that it developers, has the same (safe) utility function that the designers originally specified. A formal system can…

But can it show that it's actually running this correct algorithm to determine whether the statement about itself is probably true? There is always an external context that runs the computation. A computation never exists in "abstract space", it always happens on a physical level. Any computation is only good if it runs in the context that it was designed for. What I mean is that the AI can never "know" if it's still…

This is a good point. I think it'd be pretty interesting and useful to get a better grasp on when/whether/how a system can reason about itself as embedded in the world in a sane way.

Re: Logical Induction

#50
post #37

The article is basic mathematical research and is not intended to be implemented, but rather to guide further applied research. The deeper motivation for this article is to allow future Artificial General Intelligences to prove facts about themselves; specifically, the fact that the AGI, or a next-gen that it developers, has the same (safe) utility function that the designers originally specified. A formal system can…

> A formal system cannot in general prove that it is reliable, i.e. that if it proves statement P then P is true. I'm not entirely sure what you mean by this (I haven't read the article yet, and I'm already familiar with Loeb's theorem). It's true that you cannot show that, say, second order arithmetic is consistent in the same system. In fact, every soundness proof (for a sufficiently strong logic) will have to be c…

> This allows you to state and show meta theorems "for all (small) types", by quantifying over a universe.

As you say, this isn't quite self-trust. Another natural move is to relax the criterion of self-trust away from "it proves itself consistent" (impossible by incompleteness) towards "it assigns high probability that it has good beliefs". (Formalizations of this are in the paper.)

> At the moment I'm just confused what the problem is

In short, it would be nice to have a model of "good reasoning under deductive limitation", where "good reasoning" means something like "has accurate beliefs about all questions of interest" (for example, facts about the outputs of long-running computations), and where "deductive limitation" rules out the reasoning process "just wait for your theorem prover to decide the question".

Examples of long-running computations that are hard to compute exactly, but that we can sometimes still have reasonable beliefs about: optimal moves in chess, go, etc.; the accuracy of some ML system after a given training regimen; a weather-forecasting program that runs a gigantic series of simulations; and so on.

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