And now, a substantive response:

When Chalmers claims to have “direct” epistemic access to certain facts, the proper response is to provide the arguments for doubting that claim, not to play a verbal sleight-of-hand like Dennett’s (1991, emphasis added):

You are not authoritative about what is happening in you, but only about what seems to be happening in you, and we are giving you total, dictatorial authority over the account of how it seems to you, about what it is like to be you. And if you complain that some parts of how it seems to you are ineffable, we heterophenomenologists will grant that too. What better grounds could we have for believing that you are unable to describe something than that (1) you don’t describe it, and (2) confess that you cannot? Of course you might be lying, but we’ll give you the benefit of the doubt.

It’s intellectually dishonest of Dennett to use the word “ineffable” here to slide between the propositions “I’m unable to describe my experience” and “my experience isn’t translatable in principle”, as it is to slide between Nagel’s term of art “what it’s like to be you” and “how it seems to you”.

First of all, how in the world could you possibly know that your experience isn’t translatable in principle? That you can’t describe it—that you of course can know. But what additional meaning can it even have, to say that you can’t describe it, and on top of that, it “isn’t translatable in principle”? What does that even mean?

As far as I can tell, Dennett isn’t sliding between anything. There’s just the one meaning: you can’t describe some experience you’re having.

Secondly, it’s not clear that this paragraph is a response to claims about having “‘direct’ epistemic access to certain facts”. (I’d have to reread Consciousness Explained to see the context, but as quoted it seems a bit of a non sequitur.)

… it’s logically rude to conceal your cruxes, pretend that your method is perfectly neutral and ecumenical, and let the “scientificness” of your proposed methodology do the rhetorical pushing and pulling.

I confess I don’t really have much idea what you’re saying here. What’s Dennett concealing, exactly…?

but indeed can’t ever (without telepathy etc., or maybe not even then) be shown to another person, or perceived by another person, to be the case, that there are further facts revealed by introspection that can’t be translated into words.

There’s a version of this claim I agree with (since I’m a physicalist), but the version here is too strong. First, I want to note again that this is equating group epistemology with individual epistemology.

I wasn’t talking about group epistemology here at all, much less equating it with anything.

But even from a group’s perspective, it’s perfectly possible for “facts revealed by introspection that can’t be translated into words” to be transmitted between people; just provide someone with the verbal prompts (or other environmental stimuli) that will cause them to experience and notice the same introspective data in their own brains.

This clearly won’t do; how will you ever know that the verbal prompts (or etc.) are causing the other person to experience, much less to notice, the same “introspective data” in their brain as you experienced and noticed in yours? (How exactly do you even guarantee comparability? What does “same” even mean, across individuals? People vary, you know; and it seems fairly likely even from what we know now, that capacity to experience certain things is present to widely varying degrees in people…)

Why, there are entire reams of philosophy dedicated to precisely this very thorny challenge! (Google “spectrum inversion” sometime…) And in fact I once saw this principle play out in my own life. A musically inclined friend of mine was attempting to teach me the basics of music theory. When his initial explanations got nowhere, we opened someone’s laptop and loaded up a website where you could click buttons and play certain chords or combinations of tones. My friend clicked some buttons, played some chords, and asked me to describe what I heard, which I did… only to see my friend react with astonishment, because what I heard and what he heard turned out to be quite different. (As we later discovered, I have some interesting deficiencies/abnormalities in auditory processing, having to do, inter alia, with ability to perceive pitch.)

Now, how do you propose to cause me to experience “the same introspective data” that my friend experiences when he hears the tones and chords in question—or vice versa? What stimuli, exactly, shall you use—and how would you discover what they might be? What function, precisely, reliably maps arbitrary (stimulus X, individual A) pairs to (stimulus Y, individual B) pairs, such that the “introspective data” that is experienced (and noticed) as a result is the “same” in both cases of a set? And having on hand a candidate such function, how exactly would you ever verify that it is really the desired thing?

If that’s too vague, consider this scenario as an analogy: …

I find such fanciful analogies almost uniformly uninformative, and this one, I’m afraid, is no exception. Even if I were to stretch my brain to imagine this sort of scenario (which is not easy), and carefully consider its implications (which is quite challenging), and take the further step of drawing a conclusion about whether the given hypothetical would indeed work as you say (in which I would have quite low confidence), nevertheless it would still be entirely unclear whether, and how, the analogy mapped back to our actual world, and whether any of the reasoning and the conclusion still held. Best to avoid such things.

Indeed it’s not even clear how you’d demonstrate to yourself that what your introspection reveals is real.

You can update upward or downward about the reliability of your introspection (either in general, or in particular respects), in the same way you can update upward or downward about the reliability of your sensory perception. E.g., different introspective experiences or faculties can contradict each other, suggest their own unreliability (“I’m introspecting that this all feels like bullshit...”), or contradict other evidence sources.

What if there is no “contradiction”, as such? Surely it’s possible for introspection to be deficient or entirely misleading even so? In any case, if introspection is corrigible by comparison with “other evidence sources” (by which you presumably mean, sense data, and experimental and various other observational information acquired via sense data, etc.), then you can hardly be said to have “‘direct’ epistemic access” to anything via said introspection…

A simple sketch of how realism became unpopular

by Rob Bensinger 3 min read11th Oct 201953 comments


[Epistemic status: Sharing current impressions in a quick, simplified way in case others have details to add or have a more illuminating account. Medium-confidence that this is one of the most important parts of the story.]

Here's my current sense of how we ended up in this weird world where:

  • I still intermittently run into people who claim that there's no such thing as reality or truth;
  • a lot of 20th-century psychologists made a habit of saying things like 'minds don't exist, only behaviors';
  • a lot of 20th-century physicists made a habit of saying things like 'quarks don't exist, only minds';
  • there's a big academic split between continental thinkers saying (or being rounded off to saying) some variant of "everything is culture / perception / discourse / power" and Anglophone thinkers saying (or being rounded off to saying) "no".

Background context:

1. The ancient Greeks wrote down a whole lot of arguments. In many cases, we're missing enough textual fragments or context that we don't really know why they were arguing — what exact propositions were in dispute, or what the stakes were.

2. In any case, most of this is screened off by the fact that Europe's memetic winners were Christianity plus normal unphilosophical beliefs like "the sky is, in fact, blue".

3. Then, in 1521, the Protestant Reformation began.

4. In 1562, the Catholics found a giant list of arguments against everything by the minor Greek skeptic Sextus Empiricus, got very excited, and immediately weaponized them to show that the Protestant arguments fail (because all arguments fail).

5. These soon spread and became a sensation, and not just for being a useful superweapon. Plenty of intellectuals were earnest humanists used to taking arguments at face value, and found Sextus' arguments genuinely upsetting and fascinating.

I trace continental thinkers' "everything is subjective/relative" arguments back to a single 1710 error in George Berkeley:

[...] I am content to put the whole upon this Issue; if you can but conceive it possible for one extended moveable Substance, or in general, for any one Idea or any thing like an Idea, to exist otherwise than in a Mind perceiving it, I shall readily give up the Cause[....]
But say you, surely there is nothing easier than to imagine Trees, for instance, in a Park, or Books existing in a Closet, and no Body by to perceive them. I answer, you may so, there is no difficulty in it: But what is all this, I beseech you, more than framing in your Mind certain Ideas which you call Books and Trees, and the same time omitting to frame the Idea of any one that may perceive them? But do not you your self perceive or think of them all the while? This therefore is nothing to the purpose: It only shews you have the Power of imagining or forming Ideas in your Mind; but it doth not shew that you can conceive it possible, the Objects of your Thought may exist without the Mind: To make out this, it is necessary that you conceive them existing unconceived or unthought of, which is a manifest Repugnancy.

If I can imagine a tree that exists outside of any mind, then I can imagine a tree that is not being imagined. But "an imagined X that is not being imagined" is a contradiction. Therefore everything I can imagine or conceive of must be a mental object.

Berkeley ran with this argument to claim that there could be no unexperienced objects, therefore everything must exist in some mind — if nothing else, the mind of God.

The error here is mixing up what falls inside vs. outside of quotation marks. "I'm conceiving of a not-conceivable object" is a formal contradiction, but "I'm conceiving of the concept 'a not-conceivable object'" isn't, and human brains and natural language make it easy to mix up levels like those.

(I can immediately think of another major milestone in the history of European thought, Anselm's ontological argument for God, that shows the same brain bug.)

Berkeley's view was able to find fertile soil in an environment rife with non-naturalism, skeptical arguments, and competition between epistemic criteria and authorities. Via Kant and Kant's successors (Hegel chief among them), he successfully convinced the main current of 19th-century European philosophy to treat the idea of a "mind-independent world" as something ineffable or mysterious, and to treat experiences or perspectives as fundamental.

(Edit: G.E. Moore seems to think that everyone in the 19th century was making an error along these lines, but I now suspect Kant himself wasn't making this mistake; I think his main error was trying too hard to defeat skepticism.

I also don't think Berkeley's writing would have been sufficient to confuse Europe on its own; it's too lucid and well-articulated. The transition to Kantian and Hegelian versions of these arguments is important because they were much more elaborate and poorly expressed, requiring a lot of intellectual effort in order to spot the inconsistencies.)

My unscholarly surface impression of the turn of the 20th century is that these memes ("the territory is fundamentally mysterious" and "maps are sort of magical and cosmically important") allowed a lot of mysticism and weird metaphysics to creep into intellectual life, but that ideas like those are actually hard to justify in dry academic prose, such that the more memetically fit descendants of idealism in the 20th century ended up being quietist ("let's just run experiments and not talk about all this weird 'world' stuff") or instrumentalist / phenomenalist / skeptic / relativist ("you can't know 'world' stuff, so let's retreat to just discussing impressions; and maybe you can't even know those, so really what's left is power struggles").

Today, the pendulum has long since swung back again in most areas of intellectual life, perhaps because we've more solidly settled around our new central authority (science) and the threats to centralized epistemic authority (religious and philosophical controversy) are more distant memories. Metaphysics and weird arguments are fashionable again in analytic philosophy; behaviorism is long-dead in psychology; and quietism, non-realism, and non-naturalism at least no longer dominate the discussion in QM, though a lot of Copenhagen slogans remain popular.

The above is a very simple picture featuring uneven scholarship, and history tends to be messier than all that. (Ideas get independently rediscovered, movements go one step forward only to retreat two steps back, etc.) Also, I'm not claiming that everyone endorsed the master argument as stated, just that the master argument happened to shift intellectual fashions in this direction in a durable way.