Thus I refute Johnson

In his recent post, Alan Fox mentions Samuel Johnson in defense of the existence of external reality. He is referring, of course, to Johnson’s famous criticism of Berkeley’s idealism as described by Johnson’s biographer, James Boswell:

After we came out of the church, we stood talking for some time together of Bishop Berkeley’s ingenious sophistry to prove the non-existence of matter, and that every thing in the universe is merely ideal. I observed, that though we are satsified his doctrine is not true, it is impossible to refute it. I never shall forget the alacrity with which Johnson answered, striking his foot with mighty force against a large stone, till he rebounded from it, “I refute it thus.”

Johnson’s “refutation” has always struck me as weak and based on a misunderstanding of idealism. Did Johnson think that if idealism were true, his foot would pass through the stone unimpeded?

While I accept (provisionally) the existence of the external world, I also think that an idealism in which sight is illusory is surely capable of manifesting an illusory sense of solidity as well. Kicking the stone proved nothing.

Thus I refute Johnson, though I’m sure I’m not the first to do so.

172 thoughts on “Thus I refute Johnson

  1. keiths, as I’ve mentioned a couple of times to Neil elsewhere, I find Gibson mysterious. I’d like to understand his work better and I have some vague sense that he’s on to various important things about perception that it would be helpful for more mainstream philosophers to grok, but he’s always been off to the side of the debates about direct and indirect perception, phenomenalism, disjunctivism, etc. I don’t think he’s a good person to use as the standard bearer for the directness of perception. My own hero is Everett Hall, but if you’re looking for more recent proponents, I’d suggest Dretske, Harman and Tye. In any case, I don’t know why illusions of motion can be said to prove either the indirectness of perception or phenomenalism. All illusions are somewhat problematic for directness, but there’s a ton of literature on various ways to handle it.

    KN, I’m not exactly sure what you mean by “passive” in your remarks to the effect that DR goes off the rails by assuming that if there are constraints to perception, perception must be passive. I mean, even guys like Perry, Dawes-Hicks, and the New Realism gang recognized that perception must be at least discriminative, didn’t they? Even a tabula rasa can’t take in everything. So no receptivity can be entirely passive right off the bat.

    That’s kind of a quibble, I guess, but I don’t really understand your deeper point. For example, I don’t see how it isn’t just a kind of claim that perception is indirect. You’ve got this reality out there that we don’t actually or directly see or hear yet somehow constrains what we do actually see and hear.

    Two historical notes: my sense is that Sellars went wrong precisely in denying that sensation has any intentional aspect, i.e., in making it a purely causal relation. The key to a good theory IMO is to require that every aspect of perception is intentional, but, as indicated above, if we want to retain the empirical/realist element, it then becomes necessary to countenance the ineffable. Where I think C.I. Lewis went wrong was his thinking that we could KNOW these givens, that they provide facts which give some sort of epistemic basis for our knowledge claims. That seems to me a failure to fully recognize the radicalness of our human/cultural/linguistic/etc. contributions to what is known.

    Neil’s analogy about mountain footholds is useful here. You say the footholds are already there, Neil says (or seems to be saying) they aren’t. I’m inclined to agree with Neil about that, but it’s a precipice. Just what/where is this reality that is supposed to be constraining our perceptions? And, as Putnam points out–we don’t just want “more theory” here. My position is Tractarian/mysterian/useless: We simply can’t say. If we could, it would have to be a mistake. But not only is it there, constraining, it’s what we directly perceive.

  2. walto: keiths, as I’ve mentioned a couple of times to Neil elsewhere, I find Gibson mysterious.

    I agree with that.

    I’m an old fashioned tinkerer. I like to know how things work at the physical level. As I child, I would take a bicycle apart, and put it back together. I’m not sure I ever got as far as doing that to a clock, but I did do that to lots of things.

    I find Gibson unsatisfactory on filling in details. He leaves too much unexplained.

  3. walto: Neil’s analogy about mountain footholds is useful here. You say the footholds are already there, Neil says (or seems to be saying) they aren’t.

    Oh, the footholds are there. It’s just that there is no label on them saying “these are footholds”. The footholds are just irregularities in what would otherwise be a too smooth surface. It is up to me to pick out which irregularities I can use as footholds. The world does not dictate that to me.

    There’s a tendency to say that science is all about finding regularities. But it is the irregularities that are more important.

    The reaction of water to temperature is more-or-less regular. But the freezing point and boiling point are sharp irregularities. We anchor the Celsius scale to those irregularities.

    In speech, it is the consonants rather than the vowels that are more important. And the consonants are irregularities.

    We live in what I call a lumpy world, rather than a smooth world. Without those lumps, perception and cognition would be impossible. The lumps are real enough. But the world does not dictate which of those lumps which should pick out, nor how we should use them.

  4. BruceS,

    I still think you are talking at cross-purposes to the philosophers.

    They are using terms from a philosophical theory of the epistemology of perception, not psychology of perception.

    There’s a large overlap, and one of the commonalities is a belief that inference is absent from the perceptual process.

    My question: How can inference be absent in the case of the motion illusions? There is no actual motion, so any perceived motion must be inferred, not directly perceived.

    walto:

    In any case, I don’t know why illusions of motion can be said to prove either the indirectness of perception or phenomenalism. All illusions are somewhat problematic for directness, but there’s a ton of literature on various ways to handle it.

    How would you explain these motion illusions in terms of direct perception?

    Neil’s new thread (Direct and indirect perception) is probably a better home for this discussion, so let’s move it there.

  5. keiths:
    There’s a large overlap, and one of the commonalities is a belief that inference is absent from the perceptual process.

    My question: How can inference be absent in the case of the motion illusions?

    I have 2 concerns:

    1. I understand you to be confronting an argument about how we ought to justify perceptual knowledge by arguments involving how perception is working. I think there is a gap there, eg you have to show why such a causal explanation is the approach we ought to use to justify perception knowledge (that is what I was trying to get at by the reference to reliabilism).

    2. In his last reply to you, I read KN to be saying that he agrees that we use inference in updating the framework by which we directly perceive the world (“directly perceive” used in a philosophical level of explanation), but that is not the same as inferring the world or illusion based on a philosophical model of sense data. That is the type of inferences he wants to argue against.

    I don’t think his use of “inference” in that argument is the same as your use of “inference” in a scientific analysis of the causal chain.

    Now I am definitely going to stop talking about what I think KN means.

  6. BruceS,

    I understand you to be confronting an argument about how we ought to justify perceptual knowledge by arguments involving how perception is working.

    Here’s how it all started. KN wrote:

    On the other hand, if one rejects the Cartesian conception of mind [in which the mind has access only to its own contents, including sensations], then Berkeley’s views just don’t even get their way out of the gate.

    I replied:

    Do you believe there’s any plausible way in which we can directly apprehend external reality, rather than indirectly? (I know Neil does, but I haven’t been persuaded by his defense of Gibson, particularly when it comes to illusions.)

    The point is that I don’t see how one can argue that the mind isn’t Cartesian (in the sense described above; obviously, Cartesian dualism is bogus). Thus idealism is a live option, though not a compelling one.

  7. keiths:
    Here’s how it all started. KN wrote:

    Fair enough.
    I have concentrated on plumbing the mysteries of KN’s description of “direct perception” in his exchanges with you and me. I did not read posts which were about Idealism in much detail and so I have missed any important links there.

  8. I think BruceS has a decent grasp on what I meant — as least as good as the grasp I have on what I meant! In particular, his remark that

    BruceS: I don’t think his use of “inference” in that argument is the same as your use of “inference” in a scientific analysis of the causal chain.

    is exactly right. The contrast I’m trying to draw is between how we should describe the first-person case of perception (from the perspective of conscious subjectivity) and we should describe the third-person case (from the perspective of the scientific researcher), and I’m only defending “direct perception” with regard to the first case — obviously not the second!

    So the question is, what would rule out direct perception with regard to the first case? And does accepting causal mediation in the second case undermine direct perception in the first case?

    Keiths has been pressing me for my views on direct perception with regard to optical illusions, and it’s a hard question. I suppose my view here is that we direct perceive that the motion is only apparent.

    That is, we don’t first perceive the motion and that judge that is only apparent (though this can happen, it doesn’t mesh with my phenomenology of motion illusions) — we directly perceive that is false, by attending to such perceptual facts that, although there is a similarity in the sensations, there are all sorts of other discrepancies — such as irregularities in the relation between what is taken in through the senses and one’s bodily engagement with the object seen.

    In other words, perception is not an amalgam of (passive) sensing and (active) judging; it is a whole process with different moments of receptivity to the world and active responsiveness to the world.

    I’ll say something in a few days about how to understand the mind (even in the first-person, conscious subjective sense of the term) in radically non-Cartesian terms. This will involve drawing on some Dewey, Heidegger, Wittgenstein etc but I’ll keep the name-dropping to an absolute minimum, since I understand that that can be off-putting to some, and it doesn’t facilitate communication.

  9. In college I worked with a professor who was doing a bit of original research on subjective colors. That would be color sensations induced by alternating black and white stimuli.

    It would appear that color is digitally encoded somewhere early in the sensory chain.

    In frogs the retina simply doesn’t pass on stimuli that don’t fit the profile of a suitable target fly. The light receptors simply don’t fire.

  10. KN,

    Keiths has been pressing me for my views on direct perception with regard to optical illusions, and it’s a hard question. I suppose my view here is that we direct perceive that the motion is only apparent.

    That is, we don’t first perceive the motion and that judge that is only apparent…

    Sure we do. Any normal person perceives motion when watching TV, but only those who understand how TV works are able to recognize that the motion is illusory.

  11. Kantian Naturalist: I’ll keep the name-dropping to an absolute minimum, since I understand that that can be off-putting to some, and it doesn’t facilitate communication.

    And short sentences! And no big words! 🙂

  12. Just a reminder for Keith I asked in response to

    keiths:

    What I mean is that the idea that because our perceptions can be fooled we should consider that the world we perceive is somehow not real is just so implausible that I think it requires about as much consideration as Johnson gave it.

    That isn’t Berkeley’s argument.

    I asked:

    Was KN’s memory of the [Berkeley’s] argument reasonable?

    Would you like to give your own summary of Berkeley’s argument?

    Does Berkeley’s argument persuade you?

  13. keiths:

    Sure we do. Any normal person perceives motion when watching TV, but only those who understand how TV works are able to recognize that the motion is illusory.

    What I perceive is that I am watching pictures on TV.

    Suppose it is a baseball game.
    My experience of watching images of fly ball being caught on TV is different from watching that at a ball park which is in turn different from playing baseball and catching a fly ball myself. I as a conscious human being directly perceives that difference. (I don’t need to understand what computations my brain is performing to experience those differences as a conscious human being).

    I think you are trying to explain how the refresh rate on TV can affect the experienced motion of people watching the images, whereas KN’s point is somehow related to the first person, felt experiences of the three cases I mention.

    For me, the philosophical analog of the above argument to the cases of experiencingof illusive movement is harder to understand. I am still struggling with some of the references I mentioned. But I do see it as a different argument from understanding the subconscious brain computations for illusions.

    (Since KN posted one more, I figured I could too…).

  14. Alan:

    What I mean is that the idea that because our perceptions can be fooled we should consider that the world we perceive is somehow not real is just so implausible that I think it requires about as much consideration as Johnson gave it.

    keiths:

    That isn’t Berkeley’s argument.

    Alan asked:

    Was KN’s memory of the [Berkeley’s] argument reasonable?

    Yes, at least through step 9, in which Occam’s Razor dispenses with the material. I’m not familiar with the argument described in steps 10 through 14.

    Would you like to give your own summary of Berkeley’s argument?

    No, but I’ll explain why your description of it was inaccurate. You wrote:

    What I mean is that the idea that because our perceptions can be fooled we should consider that the world we perceive is somehow not real is just so implausible that I think it requires about as much consideration as Johnson gave it.

    Berkeley is not reasoning from the existence of illusions to the truth of idealism, mainly because the existence of detectable illusions doesn’t favor either idealism or realism. You can have illusions in both contexts.

    Does Berkeley’s argument persuade you?

    No. I prefer realism because I think it is a simpler theory that explains our observations just as well as idealism, while being more intuitive. I don’t think idealism has been refuted, however.

  15. keiths: I don’t think idealism has been refuted, however.

    There is no SEP entry on idealism. Encyclopaedia Britannica has:

    Idealism – in philosophy, any view that stresses the central role of the ideal or the spiritual in the interpretation of experience. It may hold that the world or reality exists essentially as spirit or consciousness, that abstractions and laws are more fundamental in reality than sensory things, or, at least, that whatever exists is known in dimensions that are chiefly mental—through and as ideas.

    SEP states:

    [Berkeley] was a talented metaphysician famous for defending idealism, that is, the view that reality consists exclusively of minds and their ideas

    but I see that we may have been at cross-purposes. I had formed the opinion (on little reading, I admit) that Berkeley’s arguments were not much considered at the time let alone these days, so I was reading Johnson as meaning Berkeley’s ideas did not warrant further consideration beyond a demonstration of external reality by kicking the stone.

    Regarding KN’s exposition, the last two points are critical.

    (13) and this can be only the mind of God.
    (14) hence God must exist as the cause of all of anyone’s sensations; this solves the objectivity problem and overcomes the threat of solipsism

    This is just a version of the familiar “God of the gaps” argument following the same default to”god” that is used by William Paley and the sundry versions of “intelligent design” arguments.

  16. keiths: No. I prefer realism because I think it is a simpler theory that explains our observations just as well as idealism, while being more intuitive. I don’t think idealism has been refuted, however.

    Of course, I agree about realism (of the pragmatic variety) but I just wonder whether an argument that no-one considers persuasive needs refuting or is perhaps so vaguely stated that it is irrefutable.

  17. PS Keith

    It occurs to me that perhaps some difficulty in communicating follows from you’re being an ex-smoker and me being a non-smoker. I can’t recall a time at any age when I thought the version of Christianity I was exposed to was other than made up stuff. The idea of an immaterial God and an immaterial soul are utterly meaningless to me.

    Which is why I suspect “therefore God” arguments are especially irritating to me.

  18. Alan,

    I was reading Johnson as meaning Berkeley’s ideas did not warrant further consideration beyond a demonstration of external reality by kicking the stone.

    The point of my OP is that Johnson didn’t demonstrate the existence of external reality by kicking the stone. He was being sloppy, or showboating, or both.

    Johnson’s action is perfectly compatible with Berkeley’s idealism, because the leg, the kick, and the stone might all be phenomena in an all-encompassing Mind.

    Regarding KN’s exposition, the last two points are critical.

    But note that there are really two separate arguments in KN’s summary. The first is that matter is superfluous, therefore idealism; the second is against solipsism and in favor of an idealism grounded in God’s mind.

    …I just wonder whether an argument that no-one considers persuasive needs refuting or is perhaps so vaguely stated that it is irrefutable.

    I’m not suggesting that anyone lose sleep over it, and I think it makes no practical difference, but I am suggesting that we be honest and acknowledge that the question has not been resolved. Both idealism and realism are live options. Idealism has not been refuted.

  19. There can be no refutation of idealism in my view. Or of realism either. It’s not even clear what any of that could mean.

  20. walto,

    There can be no refutation of idealism in my view. Or of realism either.

    Something we almost completely agree on! 🙂

    It’s not even clear what any of that could mean.

    You could refute either of them by showing a) that it was somehow logically inconsistent, in a heretofore overlooked way, or b) that it made a testable prediction that was contradicted by observation.

    No one has yet identified a logical inconsistency or a falsified prediction, though that of course does not prove that they don’t exist.

  21. I agree with all that. Putnam has this cute argument that purports to show that we could not be brains in a vat. But…alas.

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