A simple sketch of how realism became unpopular

My claim is that instrumentalism is the correct metaphysics regardless

What does it mean for instrumentalism to be the correct metaphysics? Normally, I'd interpret "the correct metaphysics" as saying something basic about reality or the universe. (Or, if you're an instrumentalist and you say "X is the correct metaphysics", I'd assume you were saying "it's useful to have a model that treats X as a basic fact about reality or the universe", which also doesn't make sense to me if X is "instrumentalism".)

Although it is also true that if you try interpreting quantum mechanics according to sufficiently strong realist desiderata

Well, sufficiently specific realist desiderata. Adding hidden variables to QM doesn't make the theory any more realist, the way we're using "realist" here.

It's also that a lot of philosophy, including famous works, is just really bad.

Isn't that the same argument Russell was making?

They're... similar? I find Russell a lot clearer on this point:

We might state the argument by which they support their view in some such way as this: 'Whatever can be thought of is an idea in the mind of the person thinking of it; therefore nothing can be thought of except ideas in minds; therefore anything else is inconceivable, and what is inconceivable cannot exist.'

Such an argument, in my opinion, is fallacious; and of course those who advance it do not put it so shortly or so crudely. But whether valid or not, the argument has been very widely advanced in one form or another; and very many philosophers, perhaps a majority, have held that there is nothing real except minds and their ideas.

I find Moore's way of discussing the issue weirder. Moore is definitely making an argument from 'a thought's object is different from the thought itself' to 'idealism is false', but his argument seems to involve weird steps like 'our experiences don't have contents' (rather than the expected 'the content of our experience is different from its referent'):

What I wish to point out is (1) that we have no reason for supposing that there are such things as mental images at all -- for supposing that blue is part of the content of the sensation of blue, and (2) that even if there are mental images, no mental image and no sensation or idea is merely a thing of this kind; that 'blue', even if it is part of the content of the image or sensation or idea of blue, is always also related to it in quite another way, and that this other relation, omitted in the traditional analysis, is the only one which makes the sensation of blue a mental fact at all. [...]

To have in your mind 'knowledge' of blue, is not to have in your mind a 'thing' or 'image' of which blue is the content. To be aware of the sensation of blue is not to be aware of a mental image - of a 'thing', of which 'blue' and some other element are constituent parts in the same sense in which blue and glass are constituents of a blue bead. It is to be aware of an awareness of blue; awareness being used, in both cases, in exactly the same sense. This element, we have seen, is certainly neglected by the 'content' theory: that theory entirely fails to express the fact that there is, in the sensation of blue, this unique relation between blue and the other constituent.

Baldwin (2004) confirms that this line of reasoning, plus Moore's attempt to resist skeptical hypotheses, led Moore in a very confused direction:

But what is the relationship between sense-data [i.e., the thingies we're directly conscious of] and physical objects? Moore took it that there are three serious candidates to be considered: (i) an indirect realist position, according to which sense-data are non-physical but somehow produced by interactions between physical objects and our senses; (ii) the phenomenalist position, according to which our conception of physical objects is merely one which expresses observed and anticipated uniformities among the sense-data we apprehend; (iii) a direct realist position, according to which sense-data are parts of physical objects — so that, for example, visual sense-data are visible parts of the surfaces of physical objects.

The indirect realist position is that to which he was initially drawn; but he could see that it leaves our beliefs about the physical world exposed to skeptical doubt, since it implies that the observations which constitute evidence for these beliefs concern only the properties of non-physical sense-data, and there is no obvious way for us to obtain further evidence to support a hypothesis about the properties of the physical world and its relationship to our sense-data.

This argument is reminiscent of Berkeley's critique of Locke, and Moore therefore considered carefully Berkeley's phenomenalist alternative. Moore's initial response to this position was that the implied conception of the physical world was just too ‘pickwickian’ to be believable. This may be felt to be too intuitive, like Dr. Johnson's famous objection to Berkeley; but Moore could also see that there were substantive objections to the phenomenalist position, such as the fact that our normal ways of identifying and anticipating significant uniformities among our sense-data draw on our beliefs about our location in physical space and the state of our physical sense-organs, neither of which are available to the consistent phenomenalist.

So far Moore's dialectic is familiar. What is unfamiliar is his direct realist position, according to which sense-data are physical. This position avoids the problems so far encountered, but in order to accommodate false appearances Moore has to allow that sense-data may lack the properties which we apprehend them as having. It may be felt that in so far as sense-data are objects at all, this is inevitable; but Moore now needs to provide an account of the apparent properties of sense-data and it is not clear how he can do this without going back on the initial motivation for the sense-datum theory by construing these apparent properties as properties of our experiences. But what in fact turns Moore against this direct realist position is the difficulty he thinks it leads to concerning the treatment of hallucinations. In such cases, Moore holds, any sense-data we apprehend are not parts of a physical object; so direct realism cannot apply to them, and yet there is no reason to hold that they are intrinsically different from the sense-data which we apprehend in normal experience. This last point might well be disputed, and at one point Moore himself considers the possibility of a distinction between ‘subjective’ and ‘objective’ sense-data; but once one has introduced sense-data in the first place as the primary objects of experience it is not going to be easy to make a distinction here without assuming more about experience than Moore at any rate would have wanted to concede.

Moore wrote more extensively about perception than about any other topic. In these writings he moves between the three alternatives set out here without coming to any firm conclusion.

I'd say: definitely nuanced. Definitely very inconsistent on this point. Not consistently asserting an extreme metaphysical view like "the true, mind-independent world is incomprehensibly different from the world we experience", though seeming to flirt with this view (or framing?) constantly, to the extent that all his contemporaries did think he had a view at least this weird. Mainly guilty of (a) muddled and poorly-articulated thoughts and (b) approaching epistemology with the wrong goals and methods.

The same "that sounds silly" heuristic that helps you reject Berkeley's argument (when it's fringe and 'wears its absurdity on its sleeve') helps you accept 19th-century idealists' versions of the argument (when it's respectable and framed as the modern/scientific/practical/educated/consensus view on the issue).

I should also emphasize that Berkeley's idealism is very different from (e.g.) Hegel's idealism. "Idealism" comes in enough different forms that it's probably more useful for referring to a historical phenomenon than a particular ideology. (Fortunately, the former is the topic I'm interested in here.)

Aumanns theorem assumes there is no ambiguity or disagreement about what counts as evidence or information in the first place. In the real world, that is the major barrier to achieving agreement.

The same “that sounds silly” heuristic that helps you reject Berkeley’s argument (when it’s fringe and ‘wears its absurdity on its sleeve’) helps you accept 19th-century idealists’ versions of the argument (when it’s respectable and framed as the modern/scientific/practical/educated/consensus view on the issue).

Well, maybe that is right. You haven't really argued against sophisticated idealism, or noticed that scientific realism has dumb forms.

"Heterophenomenology" might be fine as a meme for encouraging certain kinds of interesting research projects, but there are several things I dislike about how Dennett uses the idea.

Mainly, it's leaning on the social standards of scientific practice, and on a definition of what "real science" or "good science" is, to argue against propositions like "any given scientist studying consciousness should take into account their own introspective data -- e.g., the apparent character of their own visual field -- in addition to verbal descriptions, as an additional fact to explain." This is meant to serve as a cudgel and bulwark against philosophers like David Chalmers, who claim that introspection reveals further facts (/data/explananda) not strictly translatable into verbal reports.

This is framing the issue as one of social-acceptability-to-the-norms-of-scientists or conformity-with-a-definition-of-"science", whereas correct versions of the argument are Bayesian. (And it's logically rude to not make the Bayesianness super explicit and clear, given the opportunity; it obscures your premises while making your argument feel more authoritative via its association with "science" [LW · GW].)

We can imagine a weird alien race (or alien AI) that has extremely flawed sensory faculties, and very good introspection. A race like that might be able to bootstrap to good science, via leveraging their introspection to spot systematic ways in which their sensory faculties fail, and sift out the few bits of reliable information about their environments.

Humans are plausibly the opposite: as an accident of evolution, we have much more reliable sensory faculties than introspective faculties. This is a generalization from the history of science and philosophy, and from the psychology literature. Moreover, humans have a track record of being bad at distinguishing cases where their introspection is reliable from cases where it's unreliable; so it's hard to be confident of any lines we could draw between the "good introspection" and the "bad introspection". All of this is good reason to require extra standards of evidence before humanity "takes introspection at face value" and admits it into its canon of Established Knowledge.

Personally, I think consciousness is (in a certain not-clarified-here sense) an illusion, and I'm happy to express confidence that Chalmers' view is wrong. But I think Dennett has been uniquely bad at articulating the reasons Chalmers is probably wrong, often defaulting to dismissing them or trying to emphasize their social illegitimacy (as "unscientific").

The "heterophenomenology" meme strikes me as part of that project, whereas a more honest approach would say "yeah, in principle introspective arguments are totally admissible, they just have to do a bit more work than usual because we're giving them a lower prior (for reasons X, Y, Z)" and "here are specific reasons A, B, C that Chalmers' arguments don't meet the evidential bar that's required for us to take the 'autophenomenological' data at face value in this particular case".

I mean "But we should consider that bodies are [...] a mere appearance of who knows what unknown object; that motion is not the effect of this unknown cause, but merely the appearance of its influence on our senses; that consequently neither of these is something outside us, but both are merely representations in us" seems pretty unambiguous to me. Kant isn't saying here that 'we can only know stuff about mind-independent objects by using language and concepts and frameworks' in this passage; he's saying 'we can only know stuff about mere representations inside of us'.

Kant passages oscillate between making sense under one of these interpretations or the other (or neither):

• the "causality interpretation", which says that things-in-themselves are objects that cause appearances, like a mind-independent object causes an experience in someone's head. If noumena are the "true correlates" of phenomena, while phenomena are nothing but subjective experiences, then this implies that we really don't know anything about the world outside our heads. You can try to squirm out of this interpretation by asserting that words like "empirical" and "world" should be redefined to refer to subjective experiences in our heads, but this is just playing with definitions.
• the "identity interpretation", which says that things-in-themselves are the same objects as phenomena, just construed differently.

Quoting Wood (66-67, 69-70):

Yet the two interpretations appear to yield very different (incompatible) answers to the following three questions:

1. Is an appearance the very same entity as a thing in itself? The causality interpretation says no, the identity interpretation says yes.

2. Are appearances caused by things in themselves? The causality interpretation says yes, the identity interpretation says no.

3. Do the bodies we cognize have an existence in themselves? The causality interpretation says no, the identity interpretation says yes.

[... N]o entity stands to itself in the relation of cause to effect. Transcendental idealism is no intelligible doctrine at all if it cannot give self-consistent answers to the above three questions. [...]

Kant occasionally tries to combine "causality interpretation" talk with "identity interpretation" talk. When he does, the result is simply nonsense and self-contradiction:

"I say that things as objects of our senses existing outside us are given, but we know nothing of what they may be in themselves, cognizing only their appearances, that is, the representations which they cause in us by affecting our senses. Consequently, I grant by all means that there are bodies outside us, that is, things which, though quite unknown to us as to what they are in themselves, we still cognize by the representations which their influence on our sensibility procures us, and which we call bodies, a term signifying merely the appearance of the thing which is unknown to us but not the less actual. (P 4:289)

The first sentence here says that objects of the senses are given to our cognition, but then denies that we cognize these objects, saying instead that we cognize an entirely different set of objects (different from the ones he has just said are given). The second sentence infers from this that there are bodies outside us, but proceeds to say that it is not these bodies (that is, the entities Kant has just introduced to us as 'bodies') that we call 'bodies', but rather bodies are a wholly different set of entities. Such Orwellian doubletalk seems to be the inevitable result of trying to combine the causality interpretation with the identity interpretation while supposing that they are just two ways of saying the same thing. [...]

Kant of course denies that we can ever have cognition of an object as it is in itself, because we can have no sensible intuition of it -- as it is in itself. But he seems to regard it as entirely permissible and even inevitable that we should be able to think the phenomenal objects around us solely through pure concepts of the understanding, hence as they are in themselves. If I arrive at the concept of a chair in the corner first by cognizing it empirically and then by abstracting from those conditions of cognition, so that I think of it existing in itself outside those conditions, then it is obvious that I am thinking of the same object, not of two different objects. It is also clear that when I think of it the second way, I am thinking of it, and not of its cause (if it has one). From this point of view, the causality interpretation seems utterly unmotivated and even nonsensical.

The problem arises, however, because Kant also wants to arrive at the concept of a thing existing in itself in another way. He starts from the fact that our empirical cognition results from the affection of our sensibility by something outside us. This leads him to think that there must be a cause acting on our sensibility from outside, making it possible for us to intuit appearances, which are then conceived as the effects of this cause.

Of course it would be open to him to think of this for each case of sensible intuition as the appearance acting on our sensibility those a wholly empirical causality. But Kant apparently arrived at transcendental idealism in part by thinking of it as a revised version of the metaphysics of physical influence between substances that he derived from Crusius. Thus sensible intuition is sometimes thought of as the affection of our senses by an object not as an appearance but as a thing in itself, and transcendental idealism is thought of as having to claim (inconsistently) that we are to regard ourselves (as things in themselves) as being metaphysically influenced by things in themselves.

Such a metaphysics would of course be illegitimately transcendent by the standards of the Critique, but Kant unfortunately appears sometimes to think that transcendental idealism is committed to it, and many of his followers down to the present day seem addicted to the doctrine that appears to be stated in the letter of those texts that express that thought, despite the patent nonsense they involve from the critical point of view. The thing in itself is then taken to be this transcendent cause affecting our sensibility as a whole, and the appearance is seen as the ensemble of representations resulting from its activity on us.

I claim that the most natural interpretation of "[Transcendental] idealism means all specific human perceptions are moulded by the general form of human perception and there is no way to backtrack to a raw form." is that there's no way to backtrack from our beliefs, impressions, and perceptions to ultimate reality. That is, I'm interpreting "backtrack" causally: the world causes our perceptions, and backtracking would mean reconstructing what the ultimate, outside-our-heads, existed-before-humanity reality is like before we perceive or categorize it. (Or perhaps backtracking causally to the initial, relatively unprocessed sense-data our brains receive.)

In those terms, we know a ton about ultimate, outside-our-heads reality (and a decent amount about how the brain processes new sensory inputs), and there's no special obstacle to backtracking from our processed sense data to the raw, unprocessed real world. (Our reasoning faculties do need to be working OK, but that's true for our ability to learn truths about math, about our own experiences, etc. as well. Good conclusions require a good concluder.)

If instead the intended interpretation of "backtrack to a raw form" is "describe something without describing it", "think about something without thinking about it", or "reason about something without reasoning about it", then your original phrasing stops making sense to me.

Take the example of someone standing by a barn. They can see the front side of the barn, but they've never observed the back side. At noon, you ask them to describe their subjective experience of the barn, and they do so. Then you ask them to "backtrack to the raw form" beyond their experience. They proceed to start describing the full quantum state of the front of the barn as it was at noon (taking into account many-worlds: the currently-speaking observer has branched off from the original observer).

Then you go, "No, no, I meant describe something about the barn as it exists outside of your conceptual schemes." And the person repeats their quantum description, which is a true description regardless of the conceptual scheme used; the quantum state is in the world, not in my brain or in my concepts.

Then you go, "No, I meant describe an aspect of the barn that transcends your experiences entirely; not a property of the barn that caused your experience, but a property unconnected to your experience." And the person proceeds to conjecture that the barn has a back side, even though they haven't seen it; and they start speculating about likely properties the back side may have.

Then you go, "No! I meant describe something about the barn without using your concepts in the description." Or: "Describe something that bears no causal relation to your cognition whatsoever, like a causally inert quiddity that in no way interacts with any of the kinds of things you've ever experienced or computed."

And the person might reply: Well, I can say that such a thing would be a causally inert quiddity, as you say; and then perhaps I can't say much more than that, other than to drill down on what the relevant terms mean. Or, if the requirement is to describe a thing without describing it, then obviously I can't do that; but that seems like an even more trivial observation.

Why would the request to "describe something without describing it" ever be phrased as "backtracking to a raw form"? There's no "backtracking" involved, and we aren't returning to an earlier "raw" or unprocessed thing, since we're evidently not talking about an earlier (preconceptual) cognition that was subsequently processed into a proper experience; and since we're evidently not talking about the physical objects outside our heads that are the cause and referent for our thoughts about them.

I claim that there's an important equivocation at work in the idealist tradition between "backtracking" or finding a more "raw" or ultimate version of a thing, and "describe a thing without describing it". I claim that these only sound similar because of the mistake in Berkeley's master argument: confusing the ideas "an electron (i.e., an object) that exists outside of any conceptual framework" and "an 'electron' (i.e., a term or concept) that exists outside of any conceptual framework". I claim that the very temptation to use 'Ineffable-Thingie'-reifying phrasings like "there is no way to backtrack to a raw form" and "what an electron is outside of any conceptual framework", is related to this mistake.

Phrasing it as "We can't conceive of an electron without conceiving of it" makes it sound trivial, whereas the way of speaking that phrases things almost as though there were some object in the world (Kant's 'noumena') that transcends our conceptual frameworks and outstrips our every attempt to describe it, makes it sound novel and important and substantive. (And makes it an appealing Inherently Mysterious Thing [LW · GW] to worship.)