Sure, but that doesn't give epistemic license to fill the gap arbitrarily or with wishful thinking. — Relativist

To label philosophical spirituality as “wishful thinking” is to close off inquiry too quickly. These aren’t arbitrary insertions into an explanatory gap—they’re attempts to interpret the nature of that gap itself. The history of philosophy is filled with thinkers grappling rigorously with the limits of physical explanation—not because they didn’t understand science, but because they recognized that experience, meaning, and subjectivity resist reduction.

So if there's something “wishful” here, it's perhaps the wish that the scientific method could explain everything, when it was never designed to do that.

If you agree that methodological naturalism is the appropriate paradigm for the advance of science, where should the negative fact enter into my metaphysical musings? — Relativist

Methodological naturalism isn’t metaphysical naturalism, which is the attempt to apply the methods of science to the questions of philosophy. That is basically all that Chalmer’s ‘facing up to the problem of consciousness’ is saying: that the physical sciences must by design exclude a fundamental dimension of existence - the nature of being.

How should I revise my personal views on the (meta)nature of mind? Alternatives to physicalism also have explanatory gaps (e.g. the mind-body interaction problem of dualism). — Relativist

You're quite right that dualism has its own explanatory gaps—especially regarding mind-body interaction. But physicalism's own explanatory impasse around consciousness, intentionality, and meaning suggests that we shouldn't treat it as the default view merely because it's scientifically adjacent.

As for how to revise your views: simply remain open. You don't have to adopt dualism to explore non-physicalist possibilities. There are entire traditions—phenomenology, idealism, panpsychism, even non-dualist metaphysics from Eastern thought—that approach mind as primary or irreducible, without falling into obscurantism or dualism.

None of these views are without their own puzzles, but they start from a different intuition: that experience isn't something that emerges from matter, but rather something intrinsic to reality—or at least not alien to it. Even just entertaining that possibility might open new questions that physicalism can't easily ask.

Following that thread has lead me to the view that the sense of separateness, of otherness to the world, which characterises so much of modern thought, is really a form of consciousness. Thomas Nagel, in particular, puts the case in his 2012 book Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False. In a précis of his book, he says

We ourselves, as physical organisms, are part of that universe, composed of the same basic elements as everything else, and recent advances in molecular biology have greatly increased our understanding of the physical and chemical basis of life. Since our mental lives evidently depend on our existence as physical organisms, especially on the functioning of our central nervous systems, it seems natural to think that the physical sciences can in principle provide the basis for an explanation of the mental aspects of reality as well — that physics can aspire finally to be a theory of everything.

However, I believe this possibility is ruled out by the conditions that have defined the physical sciences from the beginning. The physical sciences can describe organisms like ourselves as parts of the objective spatio-temporal order – our structure and behavior in space and time – but they cannot describe the subjective experiences of such organisms or how the world appears to their different particular points of view. There can be a purely physical description of the neurophysiological processes that give rise to an experience, and also of the physical behavior that is typically associated with it, but such a description, however complete, will leave out the subjective essence of the experience – how it is from the point of view of its subject — without which it would not be a conscious experience at all.*

So the physical sciences, in spite of their extraordinary success in their own domain, necessarily leave an important aspect of nature unexplained. Further, since the mental arises through the development of animal organisms, the nature of those organisms cannot be fully understood through the physical sciences alone. Finally, since the long process of biological evolution is responsible for the existence of conscious organisms, and since a purely physical process cannot explain their existence, it follows that biological evolution must be more than just a physical process, and the theory of evolution, if it is to explain the existence of conscious life, must become more than just a physical theory.

*This is plainly a reference to the same issue that David Chalmers describes in his Facing Up to the Problem of Consciousness, which also mentions Nagel's oft-quoted 1974 paper What is it like to be a Bat?

a basic assumption of both science and philosophy: that the world is in some sense rational,
— Wayfarer

IMO, that's an unwarranted assumption. We can makes sense of the portions of reality we perceive and infer. That is not necessarily the whole of reality. I also argue that quantum mechanics isn't wholly intelligible. Rather, we grasp at it. Consider interpretations: every one of them is possible- what are we to do with that fact? I'm not a proponent of the Many-Worlds interpretation, but it's possibly true- and if so, it has significant metaphysical implications- more specific implications than the negative fact we're discussing. — Relativist

Well, to start with, I think any philosophy that declares a fortiori that the world is irrational effectively undermines itself. If reality is, at bottom, unintelligible, then all attempts at understanding—including scientific attempts—are undermined from the outset. That doesn’t mean we can grasp everything, but it does mean that the act of inquiry assumes a basic trust in the rational structure of reality.

As for quantum theory, it may well be telling us something not just about particles, but about the limits of a purely material ontology. That matter should turn out to be elusive and probabilistic rather than solid and mechanistic would not have surprised a Platonist (indeed Werner Heisenberg was a lifelong Platonist). There are many competing interpretations, of course, but several do allow for idealist or participatory readings, where observation plays an essential role. In my essay on the subject, I defend QBism (quantum baynsianism) in which the subjective act of observation is fundamental.

To label philosophical spirituality as “wishful thinking” is to close off inquiry too quickly. These aren’t arbitrary insertions into an explanatory gap—they’re attempts to interpret the nature of that gap itself. — Wayfarer

I did not suggest closing off inquiry. Rather, I value truth-seeking, and truth-seeking requires objectivity. Wishful thinking about an afterlife is seductive, not an objective path to truth.

If you agree that methodological naturalism is the appropriate paradigm for the advance of science, where should the negative fact enter into my metaphysical musings?
— Relativist

Methodological naturalism isn’t metaphysical naturalism, which is the attempt to apply the methods of science to the questions of philosophy. That is basically all that Chalmer’s ‘facing up to the problem of consciousness’ is saying: that the physical sciences must by design exclude a fundamental dimension of existence - the nature of being. — Wayfarer

I chose my words carefully, and am highlighting the fact that the "problem of consciousness" only entails the negative fact: consciousness is not entirely physical. I have repeatedly pointed out that that this negative fact explains nothing. It opens up possibilities, but possibility is cheap.

You're quite right that dualism has its own explanatory gaps—especially regarding mind-body interaction. But physicalism's own explanatory impasse around consciousness, intentionality, and meaning suggests that we shouldn't treat it as the default view merely because it's scientifically adjacent. — Wayfarer

Why ISN'T it the appropriate default view for me? Physicalism is consistent with much of mental activity and it explains a lot. You repeatedly point out (and I have accepted) that it can't be the whole truth, but you haven't proposed what more complete truth I ought to embrace. Pointing to the wide space of possibilities, that is entailed by the negative fact, is neither informative nor useful to me. You said "remain open". I am open to differences of opinion. I won't argue "you're wrong because it's contrary to physicalist dogma". I'm not trying to convince anyone to change their view, I'm just trying to decide whether or not I should change mine. Highlighting the negative fact, and the space of possibilities it opens, doesn't give me a reason to change my view of treating a physicalist account (of anything) as the appropriate default for a reductive account. I remind you, this is not some act of faith - it is just the framework I base my philosophical analyses on, and I don't apply it to human behavior or aesthetics.

...So the physical sciences, in spite of their extraordinary success in their own domain, necessarily leave an important aspect of nature unexplained. Further, since the mental arises through the development of animal organisms, the nature of those organisms cannot be fully understood through the physical sciences alone...

I have never denied that. Hurricanes.

I think any philosophy that declares a fortiori that the world is irrational unintelligible effectively undermines itself. If reality is, at bottom, unintelligible, — Wayfarer

I disagree, and that's because it is not the WORLD that is rational (or not), it is people.

As for quantum theory, it may well be telling us something not just about particles, but about the limits of a purely material ontology. — Wayfarer

It's not telling us anything other than that there's a set of possibilities, none of which would be inconsistent with materialism (by definition).

I have repeatedly pointed out that that this negative fact explains nothing. It opens up possibilities, but possibility is cheap. — Relativist

And I have repeatedly pointed out that in this ‘explanatory gap’ dwells the very self that is seeking to understand. And that deferring every question to science only perpetuates the ignoring of that. And when I do point it out, you deflect some more by framing it as a speculative question. When in reality the real question of philosophy is ‘know thyself’’

Nothing further to add.