Researcher at the Center on Long-Term Risk. All opinions my own.
here's a story where we totally fail on that first thing and the second thing turns out to matter a ton!
I'm confused as to why this is inconsistent with sequence thinking. This sounds like identifying a mechanistic story for why the policy/technical win would have good consequences, and accounting for that mechanism in your model of the overall value of working on the policy/technical win. Which a sequence thinker can do just fine.
working more directly with metrics such as "what are the most expected-value rewarding actions that a bounded agent can make given the evidence so far"
I'm not sure I exactly understand your argument, but it seems like this doesn't avoid the problem of priors, because what's the distribution w.r.t. which you define "expected-value rewarding"?
(General caveat that I'm not sure if I'm missing your point.)
Sure, there's still a "problem" in the sense that we don't have a clean epistemic theory of everything. The weights we put on the importance of different principles, and how well different credences fulfill them, will be fuzzy. But we've had this problem all along.
There are options other than (1) purely determinate credences or (2) implausibly wide indeterminate credences. To me, there are very compelling intuitions behind the view that the balance among my epistemic principles is best struck by (3) indeterminate credences that are narrow in proportion to the weight of evidence and how far principles like Occam seem to go. This isn't objective (neither are any other principles of rationality less trivial than avoiding synchronic sure losses). Maybe your intuitions differ, upon careful reflection. That doesn't mean it's a free-for-all. Even if it is, this isn't a positive argument for determinacy.
both do rely on my intuitions
My intuitions about foundational epistemic principles are just about what I philosophically endorse — in that domain, I don’t know what else we could possibly go on other than intuition. Whereas, my intuitions about empirical claims about the far future only seem worth endorsing as far as I have reasons to think they're tracking empirical reality.
it seems pretty arbitrary to me where you draw the boundary between a credence that you include in your representor vs. not. (Like: What degree of justification is enough? We'll always have the problem of induction to provide some degree of arbitrariness.)
To spell out how I’m thinking of credence-setting: Given some information, we apply different (vague) non-pragmatic principles we endorse — fit with evidence, Occam’s razor, deference, etc.
Epistemic arbitrariness means making choices in your credence-setting that add something beyond these principles. (Contrast this with mere “formalization arbitrariness”, the sort discussed in the part of the post about vagueness.)
I don’t think the problem of induction forces us to be epistemically arbitrary. Occam’s razor (perhaps an imprecise version!) favors priors that penalize a hypothesis like “the mechanisms that made the sun rise every day in the past suddenly change tomorrow”. This seems to give us grounds for having prior credences narrower than (0, 1), even if there’s some unavoidable formalization arbitrariness. (We can endorse the principle underlying Occam’s razor, “give more weight to hypotheses that posit fewer entities”, without a circular justification like “Occam’s razor worked well in the past”. Admittedly, I don’t feel super satisfied with / unconfused about Occam’s razor, but it’s not just an ad hoc thing.)
By contrast, pinning down a single determinate credence (in the cases discussed in this post) seems to require favoring epistemic weights for no reason. Or at best, a very weak reason that IMO is clearly outweighed by a principle of suspending judgment. So this seems more arbitrary to me than indeterminate credences, since it injects epistemic arbitrariness on top of formalization arbitrariness.
(I'll reply to the point about arbitrariness in another comment.)
I think it's generally helpful for conceptual clarity to analyze epistemics separately from ethics and decision theory. E.g., it's not just EV maximization w.r.t. non-robust credences that I take issue with, it's any decision rule built on top of non-robust credences. And I worry that without more careful justification, "[consequentialist] EV-maximizing within a more narrow "domain", ignoring the effects outside of that "domain"" is pretty unmotivated / just kinda looking under the streetlight. And how do you pick the domain?
(Depends on the details, though. If it turns out that EV-maximizing w.r.t. impartial consequentialism is always sensitive to non-robust credences (in your framing), I'm sympathetic to "EV-maximizing w.r.t. those you personally care about, subject to various deontological side constraints etc." as a response. Because “those you personally care about” isn’t an arbitrary domain, it’s, well, those you personally care about. The moral motivation for focusing on that domain is qualitatively different from the motivation for impartial consequentialism.)
So I'm hesitant to endorse your formulation. But maybe for most practical purposes this isn't a big deal, I'm not sure yet.
That's right.
(Not sure you're claiming otherwise, but FWIW, I think this is fine — it's true that there's some computational cost to this step, but in this context we're talking about the normative standard rather than what's most pragmatic for bounded agents. And once we start talking about pragmatic challenges for bounded agents, I'd be pretty dubious that, e.g., "pick a very coarse-grained 'best guess' prior and very coarse-grained way of approximating Bayesian updating, and try to optimize given that" would be best according to the kinds of normative standards that favor indeterminate beliefs.)
does that require you to either have the ability to commit to a plan or the inclination to consistently pick your plan from some prior epistemic perspective
You aren't required to take an action (/start acting on a plan) that is worse from your current perspective than some alternative. Let maximality-dominated mean "w.r.t. each distribution in my representor, worse in expectation than some alternative." (As opposed to "dominated" in the sense of "worse than an alternative with certainty".) Then, in general you would need[1] to ask, "Among the actions/plans that are not maximality-dominated from my current perspective, which of these are dominated from my prior perspective?" And rule those out.
If you care about diachronic norms of rationality, that is.
mostly problems with logical omnisicence not being satisfied
I'm not sure, given the "Indeterminate priors" section. But assuming that's true, what implication are you drawing from that? (The indeterminacy for us doesn't go away just because we think logically omniscient agents wouldn't have this indeterminacy.)
the arbitrariness of the prior is just a fact of life
The arbitrariness of a precise prior is a fact of life. This doesn't imply we shouldn't reduce this arbitrariness by having indeterminate priors.
The obvious answer is only when there is enough indeterminacy to matter; I'm not sure if anyone would disagree. Because the question isn't whether there is indeterminacy, it's how much, and whether it's worth the costs of using a more complex model instead of doing it the Bayesian way.
Based on this I think you probably mean something different by “indeterminacy” than I do (and I’m not sure what you mean). Many people in this community explicitly disagree with the claim that our beliefs should be indeterminate at all, as exemplified by the objections I respond to in the post.
When you say “whether it’s worth the costs of using a more complex model instead of doing it the Bayesian way”, I don’t know what “costs” you mean, or what non-question-begging standard you’re using to judge whether “doing it the Bayesian way” would be better. As I write in the “Background” section: "And it’s question-begging to claim that certain beliefs “outperform” others, if we define performance as leading to behavior that maximizes expected utility under those beliefs. For example, it’s often claimed that we make “better decisions” with determinate beliefs. But on any way of making this claim precise (in context) that I’m aware of, “better decisions” presupposes determinate beliefs!"
You also didn't quite endorse suspending judgement in that case - "If someone forced you to give a best guess one way or the other, you suppose you’d say “decrease”.
The quoted sentence is consistent with endorsing suspending judgment, epistemically speaking. As the key takeaways list says, “If you’d prefer to go with a given estimate as your “best guess” when forced to give a determinate answer, that doesn’t imply this estimate should be your actual belief.”
But if it is decision relevant, and there is only a binary choice available, your best guess matters
I address this in the “Practical hallmarks” section — what part of my argument there do you disagree with?
I worry there's kind of a definitional drift going on here. I guess Holden doesn't give a super clean definition in the post, but AFAICT these quotes get at the heart of the distinction:
"Making a decision based on a single model of the world" vs. "combining different perspectives by weighing their conclusions against each other" seems orthogonal to the failure mode you mention. (Which is a failure to account for a mechanism that the "cluster thinker" here explicitly foresees.) I'm not sure if you're claiming that empirically, people who follow sequence thinking have a track record of this failure mode? If so, I guess I'm just suspicious of that claim and would expect it's grounded mostly in vibes.