When I say an AI A is aligned with an operator H, I mean:
A is trying to do what H wants it to do.
The “alignment problem” is the problem of building powerful AI systems that are aligned with their operators.
This is significantly narrower than some other definitions of the alignment problem, so it seems important to clarify what I mean.
In particular, this is the problem of getting your AI to try to do the right thing, not the problem of figuring out which thing is right. An aligned AI would try to figure out which thing is right, and like a human it may or may not succeed.
Analogy
Consider a human assistant who is trying their hardest to do what H wants.
I’d say this assistant is aligned with H. If we build an AI that has an analogous relationship to H, then I’d say we’ve solved the alignment problem.
“Aligned” doesn’t mean “perfect:”
- They could misunderstand an instruction, or be wrong about what H wants at a particular moment in time.
- They may not know everything about the world, and so fail to recognize that an action has a particular bad side effect.
- They may not know everything about H’s preferences, and so fail to recognize that a particular side effect is bad.
- They may build an unaligned AI (while attempting to build an aligned AI).
I use alignment as a statement about the motives of the assistant, not about their knowledge or ability. Improving their knowledge or ability will make them a better assistant — for example, an assistant who knows everything there is to know about H is less likely to be mistaken about what H wants — but it won’t make them more aligned.
(For very low capabilities it becomes hard to talk about alignment. For example, if the assistant can’t recognize or communicate with H, it may not be meaningful to ask whether they are aligned with H.)
Clarifications
- The definition is intended de dicto rather than de re. An aligned A is trying to “do what H wants it to do.” Suppose A thinks that H likes apples, and so goes to the store to buy some apples, but H really prefers oranges. I’d call this behavior aligned because A is trying to do what H wants, even though the thing it is trying to do (“buy apples”) turns out not to be what H wants: the de re interpretation is false but the de dicto interpretation is true.
- An aligned AI can make errors, including moral or psychological errors, and fixing those errors isn’t part of my definition of alignment except insofar as it’s part of getting the AI to “try to do what H wants” de dicto. This is a critical difference between my definition and some other common definitions. I think that using a broader definition (or the de re reading) would also be defensible, but I like it less because it includes many subproblems that I think (a) are much less urgent, (b) are likely to involve totally different techniques than the urgent part of alignment.
- An aligned AI would also be trying to do what H wants with respect to clarifying H’s preferences. For example, it should decide whether to ask if H prefers apples or oranges, based on its best guesses about how important the decision is to H, how confident it is in its current guess, how annoying it would be to ask, etc. Of course, it may also make a mistake at the meta level — for example, it may not understand when it is OK to interrupt H, and therefore avoid asking questions that it would have been better to ask.
- This definition of “alignment” is extremely imprecise. I expect it to correspond to some more precise concept that cleaves reality at the joints. But that might not become clear, one way or the other, until we’ve made significant progress.
- One reason the definition is imprecise is that it’s unclear how to apply the concepts of “intention,” “incentive,” or “motive” to an AI system. One naive approach would be to equate the incentives of an ML system with the objective it was optimized for, but this seems to be a mistake. For example, humans are optimized for reproductive fitness, but it is wrong to say that a human is incentivized to maximize reproductive fitness.
- “What H wants” is even more problematic than “trying.” Clarifying what this expression means, and how to operationalize it in a way that could be used to inform an AI’s behavior, is part of the alignment problem. Without additional clarity on this concept, we will not be able to build an AI that tries to do what H wants it to do.
Postscript on terminological history
I originally described this problem as part of “the AI control problem,” following Nick Bostrom’s usage in Superintelligence, and used “the alignment problem” to mean “understanding how to build AI systems that share human preferences/values” (which would include efforts to clarify human preferences/values).
I adopted the new terminology after some people expressed concern with “the control problem.” There is also a slight difference in meaning: the control problem is about coping with the possibility that an AI would have different preferences from its operator. Alignment is a particular approach to that problem, namely avoiding the preference divergence altogether (so excluding techniques like “put the AI in a really secure box so it can’t cause any trouble”). There currently seems to be a tentative consensus in favor of this approach to the control problem.
I don’t have a strong view about whether “alignment” should refer to this problem or to something different. I do think that some term needs to refer to this problem, to separate it from other problems like “understanding what humans want,” “solving philosophy,” etc.
This post was originally published here on 7th April 2018.
The next post in this sequence will post on Saturday, and will be "An Unaligned Benchmark" by Paul Christiano.
Tomorrow's AI Alignment Sequences post will be the first in a short new sequence of technical exercises from Scott Garrabrant.
Hmm. I appreciate the effort, but I don't understand this answer. Maybe discussing this point further is not productive in this format.
Yes, and in that perspective, the mathematical model can tell me about resonance. It's actually incredibly easy: resonance appears already in simple harmonic oscillators. Moreover, even if I did not explicitly understand resonance, if I proved that the bridge is stable under certain assumptions about external forces magnitudes and spacetime spectrum, it automatically guarantees that resonance will not crash the bridge (as long as the assumptions are realistic). Obviously people have not been so cautious over history, but that doesn't mean we should be careless about AGI as well.
I understand the argument that sometimes creating and analyzing a realistic mathematical model is difficult. I agree that under time pressure it might be better to compromise on a combination of unrealistic mathematical models, empirical data and informal reasoning. But I don't understand why should we give up so soon? We can work towards realistic mathematical models and prepare fallbacks, and even if we don't arrive at a realistic mathematical model it is likely that the effort will produce valuable insights.
First, if I am asked to check whether an element is in an array, or some other easy manipulation of data structures, I obviously don't literally start proving a theorem with pencil and paper. However, my not-fully-formal reasoning is such that I could prove a theorem if I wanted to. My model is not exactly "intuitive": I could explicitly explain every step. And, this is exactly how all of mathematics works! Mathematicians don't write proofs that are machine verifiable (some people do that today, but it's a novel and tiny fraction of mathematics). They write proofs that are good enough so that all the informal steps can be easily made formal by anyone with reasonable background in the field (but actually doing that would be very labor intensive).
Second, what I actually meant is examples like, I am using an algorithm to solve a system of linear equations, or find the maximal matching in a graph, or find a rotation matrix that minimizes the sum of square distances between two sets, because I have a proof that this algorithm works (or, in some cases, a proof that it at least produces the right answer when it converges). Moreover, this applies to problems that explicitly involve the physical world as well, such as Kalman filters or control loops.
Of course, in the latter case we need to make some assumptions about the physical world in order to prove anything. It's true that in applications the assumptions are often false, and we merely hope that they are good enough approximations. But, when the extra effort is justified, we can do better: we can perform a mathematical analysis of how much the violation of these assumptions affects the result. Then, we can use outside knowledge to verify that the violations are within the permissible margin.
Third, we could also literally prove machine-verifiable theorems about the code. This is called formal verification, and people do that sometimes when the stakes are high (as they definitely are with AGI), although in this case I have no personal experience. But, this is just a "side benefit" of what I was talking about. We need the mathematical theory to know that our algorithms are safe. Formal verification "merely" tells us that the implementation doesn't have bugs (which is something we should definitely worry about too, when it becomes relevant).
I'm not sure about the scope of your question? I made a sandwich this morning without building mathematical theory :) I think that the AI safety community definitely produced some important arguments about AI risk, and these arguments are valid evidence. But, I consider most of the big questions to be far from settled, and I don't see how they could be settled only with this kind of reasoning.