I like this review and think it was very helpful in understanding your (Abram's) perspective, as well as highlighting some flaws in the original post, and ways that I'd been unclear in communicating my intuitions. In the rest of my comment I'll try write a synthesis of my intentions for the original post with your comments; I'd be interested in the extent to which you agree or disagree.
We can distinguish between two ways to understand a concept X. For lack of better terminology, I'll call them "understanding how X functions" and "understanding the nature of X". I conflated these in the original post in a confusing way.
For example, I'd say that studying how fitness functions would involve looking into the ways in which different components are important for the fitness of existing organisms (e.g. internal organs; circulatory systems; etc). Sometimes you can generalise that knowledge to organisms that don't yet exist, or even prove things about those components (e.g. there's probably useful maths connecting graph theory with optimal nerve wiring), but it's still very grounded in concrete examples. If we thought that we should study how intelligence functions in a similar way as we study how fitness functions, that might look like a combination of cognitive science and machine learning.
By comparison, understanding the nature of X involves performing a conceptual reduction on X by coming up with a theory which is capable of describing X in a more precise or complete way. The pre-theoretic concept of fitness (if it even existed) might have been something like "the number and quality of an organism's offspring". Whereas the evolutionary notion of fitness is much more specific, and uses maths to link fitness with other concepts like allele frequency.
Momentum isn't really a good example to illustrate this distinction, so perhaps we could use another concept from physics, like electricity. We can understand how electricity functions in a lawlike way by understanding the relationship between voltage, resistance and current in a circuit, and so on, even when we don't know what electricity is. If we thought that we should study how intelligence functions in a similar way as the discoverers of electricity studied how it functions, that might involve doing theoretical RL research. But we also want to understand the nature of electricity (which turns out to be the flow of electrons). Using that knowledge, we can extend our theory of how electricity functions to cases which seem puzzling when we think in terms of voltage, current and resistance in circuits (even if we spend almost all our time still thinking in those terms in practice). This illustrates a more general point: you can understand a lot about how something functions without having a reductionist account of its nature - but not everything. And so in the long term, to understand really well how something functions, you need to understand its nature. (Perhaps understanding how CS algorithms work in practice, versus understanding the conceptual reduction of algorithms to Turing Machines, is another useful example).
I had previously thought that MIRI was trying to understand how intelligence functions. What I take from your review is that MIRI is first trying to understand the nature of intelligence. From this perspective, your earlier objection makes much more sense.
However, I still think that there are different ways you might go about understanding the nature of intelligence, and that "something kind of like rationality realism" might be a crux here (as you mention). One way that you might try to understand the nature of intelligence is by doing mathematical analysis of what happens in the limit of increasing intelligence. I interpret work on AIXI, logical inductors, and decision theory as falling into this category. This type of work feels analogous to some of Einstein's thought experiments about the limit of increasing speed. Would it have worked for discovering evolution? That is, would starting with a pre-theoretic concept of fitness and doing mathematical analysis of its limiting cases (e.g. by thinking about organisms that lived for arbitrarily long, or had arbitrarily large numbers of children) have helped people come up with evolution? I'm not sure. There's an argument that Malthus did something like this, by looking at long-term population dynamics. But you could also argue that the key insights leading up to the discovery evolution were primarily inspired by specific observations about the organisms around us. And in fact, even knowing evolutionary theory, I don't think that the extreme cases of fitness even make sense. So I would say that I am not a realist about "perfect fitness", even though the concept of fitness itself seems fine.
So an attempted rephrasing of the point I was originally trying to make, given this new terminology, is something like "if we succeed in finding a theory that tells us the nature of intelligence, it still won't make much sense in the limit, which is the place where MIRI seems to be primarily studying it (with some exceptions, e.g. your Partial Agency sequence). Instead, the best way to get that theory is to study how intelligence functions."
The reason I called it "rationality realism" not "intelligence realism" is that rationality has connotations of this limit or ideal existing, whereas intelligence doesn't. You might say that X is very intelligent, and Y is more intelligent than X, without agreeing that perfect intelligence exists. Whereas when we talk about rationality, there's usually an assumption that "perfect rationality" exists. I'm not trying to argue that concepts which we can't formalise "aren't real", but rather that some concepts become incoherent when extrapolated a long way, and this tends to occur primarily for concepts which we can't formalise, and that it's those incoherent extrapolations like "perfect fitness" which "aren't real" (I agree that this was quite unclear in the original post).
My proposed redefinition:
Epistemic status: trying to vaguely gesture at vague intuitions. A similar idea was explored here under the heading "the intelligibility of intelligence", although I hadn't seen it before writing this post. As of 2020, I consider this follow-up comment to be a better summary of the thing I was trying to convey with this post than the post itself. The core disagreement is about how much we expect the limiting case of arbitrarily high intelligence to tell us about the AGIs whose behaviour we're worried about.
There’s a mindset which is common in the rationalist community, which I call “realism about rationality” (the name being intended as a parallel to moral realism). I feel like my skepticism about agent foundations research is closely tied to my skepticism about this mindset, and so in this essay I try to articulate what it is.
Humans ascribe properties to entities in the world in order to describe and predict them. Here are three such properties: "momentum", "evolutionary fitness", and "intelligence". These are all pretty useful properties for high-level reasoning in the fields of physics, biology and AI, respectively. There's a key difference between the first two, though. Momentum is very amenable to formalisation: we can describe it using precise equations, and even prove things about it. Evolutionary fitness is the opposite: although nothing in biology makes sense without it, no biologist can take an organism and write down a simple equation to define its fitness in terms of more basic traits. This isn't just because biologists haven't figured out that equation yet. Rather, we have excellent reasons to think that fitness is an incredibly complicated "function" which basically requires you to describe that organism's entire phenotype, genotype and environment.
In a nutshell, then, realism about rationality is a mindset in which reasoning and intelligence are more like momentum than like fitness. It's a mindset which makes the following ideas seem natural:
To be clear, I am neither claiming that realism about rationality makes people dogmatic about such ideas, nor claiming that they're all false. In fact, from a historical point of view I’m quite optimistic about using maths to describe things in general. But starting from that historical baseline, I’m inclined to adjust downwards on questions related to formalising intelligent thought, whereas rationality realism would endorse adjusting upwards. This essay is primarily intended to explain my position, not justify it, but one important consideration for me is that intelligence as implemented in humans and animals is very messy, and so are our concepts and inferences, and so is the closest replica we have so far (intelligence in neural networks). It's true that "messy" human intelligence is able to generalise to a wide variety of domains it hadn't evolved to deal with, which supports rationality realism, but analogously an animal can be evolutionarily fit in novel environments without implying that fitness is easily formalisable.
Another way of pointing at rationality realism: suppose we model humans as internally-consistent agents with beliefs and goals. This model is obviously flawed, but also predictively powerful on the level of our everyday lives. When we use this model to extrapolate much further (e.g. imagining a much smarter agent with the same beliefs and goals), or base morality on this model (e.g. preference utilitarianism, CEV), is that more like using Newtonian physics to approximate relativity (works well, breaks down in edge cases) or more like cavemen using their physics intuitions to reason about space (a fundamentally flawed approach)?
Another gesture towards the thing: a popular metaphor for Kahneman and Tversky's dual process theory is a rider trying to control an elephant. Implicit in this metaphor is the localisation of personal identity primarily in the system 2 rider. Imagine reversing that, so that the experience and behaviour you identify with are primarily driven by your system 1, with a system 2 that is mostly a Hansonian rationalisation engine on top (one which occasionally also does useful maths). Does this shift your intuitions about the ideas above, e.g. by making your CEV feel less well-defined? I claim that the latter perspective is just as sensible as the former, and perhaps even more so - see, for example, Paul Christiano's model of the mind, which leads him to conclude that "imagining conscious deliberation as fundamental, rather than a product and input to reflexes that actually drive behavior, seems likely to cause confusion."
These ideas have been stewing in my mind for a while, but the immediate trigger for this post was a conversation about morality which went along these lines:
I had a lot of difficulty in figuring out what I actually meant during that conversation, but I think a quick way to summarise the disagreement is that O is a rationality realist, and I’m not. This is not a problem, per se: I'm happy that some people are already working on AI safety from this mindset, and I can imagine becoming convinced that rationality realism is a more correct mindset than my own. But I think it's a distinction worth keeping in mind, because assumptions baked into underlying worldviews are often difficult to notice, and also because the rationality community has selection effects favouring this particular worldview even though it doesn't necessarily follow from the community's founding thesis (that humans can and should be more rational).