This going to be a somewhat-scattered summary of my own current understanding. My understanding of this question has evolved over time, and is therefore likely to continue to evolve over time.
First, there's all the classic coherence theorems - think Complete Class or Savage or Dutch books or any of the other arguments you'd find in Stanford Encyclopedia of Philosophy. The general pattern of these is:
I would group objections to this sort of theorem into three broad classes:
For an old answer to (2.a), see the discussion under my mini-essay comment on Coherent Decisions Imply Consistent Utilities. (We'll also talk about (2.a) some more below.) Other than that particularly common confusion, there's a whole variety of other confusions; a few common types include:
While I think EJT's arguments specifically are not quite right in a few ways, there is an importantly correct claim close to his: none of the classic coherence theorems say "powerful agent -> EU maximizer (in a nontrivial sense)". They instead say "<list of properties which are not obviously implied by powerful agency> -> EU maximizer". In order to even start to make a theorem of the form "powerful agent -> EU maximizer (in a nontrivial sense)", we'd first need a clean intuitively-correct mathematical operationalization of what "powerful agent" even means.
Currently, the best method I know of for making the connection between "powerful agency" and utility maximization is in Utility Maximization = Description Length Minimization. There, the notion of "powerful agency" is tied to optimization, in the sense of pushing the world into a relatively small number of states. That, in turn, is equivalent (the post argues) to expected utility maximization. That said, that approach doesn't explicitly talk about "an agent" at all; I see it less as a coherence theorem and more as a likely-useful piece of some future coherence theorem.
What would the rest of such a future coherence theorem look like? Here's my current best guess:
There are various claims along the lines of "agent behaves like <X>, or else it's executing a pareto-suboptimal/dominated strategy".
Some of these are very easy to prove; here's my favorite example. An agent has a fixed utility function and performs pareto-optimally on that utility function across multiple worlds (so "utility in each world" is the set of objectives). Then there's a normal vector (or family of normal vectors) to the pareto surface at whatever point the agent achieves. (You should draw a picture at this point in order for this to make sense.) That normal vector's components will all be nonnegative (because pareto surface), and the vector is defined only up to normalization, so we can interpret that normal vector as a probability distribution. That also makes sense intuitively: larger components of that vector (i.e. higher probabilities) indicate that the agent is "optimizing relatively harder" for utility in those worlds. This says nothing at all about how the agent will update, and we'd need a another couple sentences to argue that the agent maximizes expected utility under the distribution, but it does give the prototypical mental picture behind the "pareto-optimal -> probabilities" idea.
The most fundamental and general problem with pareto-optimality-based claims is that "pareto-suboptimal" implies that we already had a set of quantitative objectives in mind (or in some cases a "measuring stick of utility", like e.g. money). But then some people will say "ok, but what if a powerful agent just isn't pareto-optimal with respect to any resources at all, for instance because it just produces craptons of resources and then uses them inefficiently?".
(Aside: "'pareto-suboptimal' implies we already had a set of quantitative objectives in mind" is also usually the answer to claims that all systems can be represented as expected utility maximizers. Sure, any system can be represented as an expected utility maximizer which is pareto-optimal with respect to some made-up objectives/resources which we picked specifically for this system. That does not mean all systems are pareto-optimal with respect to money, or energy, or other resources which we actually care about. Or, if using Utility Maximization = Description Length Minimization to ground out the quantitative objectives: not all systems are pareto-optimal with respect to optimization of some stuff far away in the world. That's where the nontrivial content of most coherence theorems comes from: the quantitative objectives with respect to which the agent is pareto-optimal need to be things we care about for some reason.)
What if a powerful agent just isn't pareto-optimal with respect to any resources or far-away optimization targets at all? Or: even if you do expect powerful agents to be approximately pareto-optimal, presumably they will be approximately pareto optimal, not exactly pareto-optimal. What can we say about coherence then?
To date, I know of no theorems saying anything at all about approximate coherence. That said, this looks like more a case of "nobody's done the legwork yet" rather than "people tried and failed". It's on my todo list.
My guess is that there's a way to come at the problem with a thermodynamics-esque flavor, which would yield global bounds, for instance of roughly the form "in order for the system to apply n bits of optimization more than it could achieve with outputs independent of its inputs, it must observe at least m bits and approximate coherence to within m-n bits" (though to be clear I don't yet know the right ways to operationalize all the parts of that sentence). The simplest version of a theorem of that form doesn't work, but David and I have played with some variations and have some promising threads.
I remember reading the EJT post and left some comments there. The basic conclusions I arrived at are:
In my current thinking about non-coherent agents, the main toy example I like to think about is the agent that maximizes some combination of the entropy of its actions, and their expected utility. i.e. the probability of taking an action is proportional to up to a normalization factor. By tuning we can affect whether the agent cares more about entropy or utility. This has a great resemblance to RLHF-finetuned language models. They're trained to both achieve a high rating and to not have too great an entropy with respect to the prior implied by pretraining.
I’m coming to this two weeks late, but here are my thoughts.
The question of interest is:
Rephrased:
Coherence arguments purport to establish that the answer is yes. These arguments go like this:
These arguments don’t work, because premise 1 is false: there are no theorems which imply that, unless an agent can be represented as maximizing expected utility, that agent is liable to pursue dominated strategies. In the year since I published my post, no one has disputed that.
Now to address two prominent responses:
In the post, I used the term ‘coherence theorems’ to refer to ‘theorems which imply that, unless an agent can be represented as maximizing expected utility, that agent is liable to pursue dominated strategies.’ I took that to be the usual definition on LessWrong (see the Appendix for why), but some people replied that they meant something different by ‘coherence theorems’: e.g. ‘theorems that are relevant to the question of agent coherence.’
All well and good. If you use that definition, then there are coherence theorems. But if you use that definition, then coherence theorems can’t play the role that they’re supposed to play in coherence arguments. Premise 1 of the coherence argument is still false. That’s the important point.
This is a crude summary of Rohin’s response. Rohin and I agree that the Complete Class Theorem implies the following: ‘If an agent has complete and transitive preferences, then unless the agent can be represented as maximizing expected utility, that agent is liable to pursue dominated strategies.’ So the mistake is neglecting to say ‘If an agent has complete and transitive preferences…’ Rohin thinks this mistake is benign.
I don’t think the mistake is benign. As my rephrasing of the question of interest above makes clear, Completeness and Transitivity are a major part of what coherence arguments aim to establish! So it’s crucial to note that the Complete Class Theorem gives us no reason to think that sufficiently-advanced artificial agents will have complete or transitive preferences, especially since:
Here are two important points, which I make to preclude misreadings of the post:
Coherence arguments don’t work, but there might well be other reasons to think that future artificial agents - trained in a standard way - will be representable as maximizing expected utility.
The post matters because ‘train artificial agents to have incomplete preferences’ looks promising as a way of ensuring that these agents allow us to shut them down.
AI safety researchers haven’t previously considered incomplete preferences as a solution, plausibly because these researchers accepted coherence arguments and so thought that agents with incomplete preferences were a non-starter.[1] But coherence arguments don’t work, so training agents to have incomplete preferences is back on the table as a strategy for reducing risks from AI. And (I think) it looks like a pretty good strategy. I make the case for it in this post, and my coauthors and I will soon be posting some experimental results suggesting that the strategy is promising.
As I wrote elsewhere:
The List of Lethalities mention of ‘Corrigibility is anti-natural to consequentialist reasoning’ points to Corrigibility (2015) and notes that MIRI failed to find a formula for a shutdownable agent. MIRI failed because they only considered agents with complete preferences. Useful agents with complete (and transitive and option-set-independent) preferences will often have some preference regarding the pressing of the shutdown button, as this theorem shows. MIRI thought that they had to assume completeness, because of coherence arguments. But coherence arguments are mistaken: there are no theorems which imply that agents must have complete preferences in order to avoid pursuing dominated strategies. So we can relax the assumption of completeness and use this extra leeway to find a formula for a corrigible consequentialist. That formula is what I purport to give in this post.
I guess I just don’t see it as a weak point in the doom argument that goal-orientedness is a convergent attractor in the space of self-modifying intelligences?
It feels similar to pondering the familiar claim of evolution, that systems that copy themselves and seize resources are an attractor state. Sure it’s not 100% proven but it seems pretty solid.
(edit: discussions in the comments section have led me to realize there have been several conversations on LessWrong related to this topic that I did not mention in my original question post.
Since ensuring their visibility is important, I am listing them here: Rohin Shah has explained how consequentialist agents optimizing for universe-histories rather than world-states can display any external behavior whatsoever, Steven Byrnes has explored corrigibility in the framework of consequentialism by arguing poweful agents will optimize for future world-states at least to some extent, Said Achmiz has explained what incomplete preferences look like (1, 2, 3), EJT has formally defined preferential gaps and argued incomplete preferences can be an alignment strategy, John Wentworth has analyzed incomplete preferences through the lens of subagents but has then argued that incomplete preferences imply the existence of dominated strategies, and Sami Petersen has argued Wentworth was wrong by showing how incomplete preferences need not be vulnerable.)
In his first discussion with Richard Ngo during the 2021 MIRI Conversations, Eliezer retrospected and lamented:
Eliezer is essentially claiming that, just as his pessimism compared to other AI safety researchers is due to him having engaged with the relevant concepts at a concrete level ("So I have a general thesis about a failure mode here which is that, the moment you try to sketch any concrete plan or events which correspond to the abstract descriptions, it is much more obviously wrong, and that is why the descriptions stay so abstract in the mouths of everybody who sounds more optimistic than I am. This may, perhaps, be confounded by the phenomenon where I am one of the last living descendants of the lineage that ever knew how to say anything concrete at all"), his experience with and analysis of powerful optimization allows him to be confident in what the cognition of a powerful AI would be like. In this view, Vingean uncertainty prevents us from knowing what specific actions the superintelligence would take, but effective cognition runs on Laws that can nonetheless be understood and which allow us to grasp the general patterns (such as Instrumental Convergence) of even an "alien mind" that's sufficiently powerful. In particular, any (or virtually any) sufficiently advanced AI must be a consequentialist optimizer that is an agent as opposed to a tool and which acts to maximize expected utility according to its world model to purse a goal that can be extremely different from what humans deem good.
When Eliezer says "they did not even do as many homework problems as I did," I doubt he is referring to actual undergrad-style homework problems written nicely in LaTeX. Nevertheless, I would like to know whether there is some sort of publicly available repository of problem sets that illustrate the principles he is talking about. Meaning set-ups where you have an agent (of sorts) that is acting in a manner that's either not utility-maximizing or even simply not consequentialist, followed by explanations of how you can exploit this agent. Given the centrality of consequentialism (and the associated money-pump and Dutch book-type arguments) to his thinking about advanced cognition and powerful AI, it would be nice to be able to verify whether working on these "homework problems" indeed results in the general takeaway Eliezer is trying to communicate.
I am particularly interested in this question in light of EJT's thorough and thought-provoking post on how "There are no coherence theorems". The upshot of that post can be summarized as saying that "there are no theorems which state that, unless an agent can be represented as maximizing expected utility, that agent is liable to pursue strategies that are dominated by some other available strategy" and that "nevertheless, many important and influential people in the AI safety community have mistakenly and repeatedly promoted the idea that there are such theorems."
I was not a member of this site at the time EJT made his post, but given the large number of upvotes and comments on his post (123 and 116, respectively, at this time), it appears likely that it was rather popular and people here paid some attention to it. In light of that, I must confess to finding the general community reaction to his post rather baffling. Oliver Habryka wrote in response:
However, the "details", as far as I can tell, have never been written up. There was one other post by Valdes on this topic, who noted that "I have searched for a result in the literature that would settle the question and so far I have found none" and explicitly called for the community's participation, but constructive engagement was minimal. John Wentworth, for his part, wrote a nice short explanation of what coherence looks like in a toy setting involving cache corruption and a simple optimization problem; this was interesting but not quite on point to what EJT talked about. But this was it; I could not find any other posts (written after EJT's) that were even tangentially connected to these ideas. Eliezer's own response was dismissive and entirely inadequate, not really contending with any of the arguments in the original post:
As EJT explained in detail,
This whole situation appears very strange to me, as an outsider; isn't this topic important enough to merit enough of an analysis that gets us beyond saying (in Habryka's words) "it does seem wrong" to "it's actually wrong, here's the math that proves it"? I tried quite hard to find one, and was not able to. Given that coherence arguments are still crucial argumentative building blocks of the case made by users here that AI risk should be taken seriously (and that the general format of these arguments has remained unchanged), it leaves me with the rather uncanny impression that EJT's post was seen by the community, acknowledged as important, yet never truly engaged with, and essentially... forgotten, or maybe ignored? It doesn't seem like it has changed anyone's behavior or arguments despite no refutation of it having appeared. Am I missing something important here?