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. To the best of my knowledge, “idealism” is not a word that Berkeley uses to describe his own view. To some degree it’s an anachronism.

    Berkeley’s foremost is to defeat skepticism and materialism, and to that end his view is an “immaterialism”. By that, I mean that he positively denies the existence of material things. But he is also a foremost proponent of empiricism. This is part of what makes Berkeley interesting — normally we today take empiricism and physicalism to be natural allies, whereas Berkeley thinks that, properly understood, they are opposed to one another.

    His denial of the existence of physical things is motivated in part by the causal interaction problem that sets in if we accept dualism — that there are both mental things (minds or, in his terms, “spirits”) and physical things (in his terms, “bodies”). No one in the 17th and 18th centuries could see how physical and mental things could possibly interact causally — not even Descartes, who invented the problem. Everyone back then saw that Descartes’s invocation of the pineal gland as the site where the “animal spirits” causally impinged upon the mind was a shameless dodge.

    But rejecting the existence of the mind didn’t seem terribly plausible, and with good reason — it doesn’t make sense to say that consciousness and mental content simply don’t exist. Given the bad options — dualism and materialism — Berkeley’s insight is that denying the existence of material objects is a way out. But what makes it really attractive is that this denial is based on empiricist grounds: that what we perceive is only one’s own sensations and not anything “material”, so “matter” becomes no more than a theoretical posit — and, as Berkeley goes on to argue, an eminently dispensable one on the basis of Occam’s Razor.

  2. Neil Rickert: Berkeley is also known for his opposition to the idea of abstract objects.

    Right! And that opposition comes right out of his steadfast commitment to empiricism and plays an important role in his view that the word “matter” is a mere empty sound — that we have no idea (in the peculiar 17th-century sense of that word) of “matter”.

  3. But rejecting the existence of the mind didn’t seem terribly plausible, and with good reason — it doesn’t make sense to say that consciousness and mental content simply don’t exist. Given the bad options — dualism and materialism — Berkeley’s insight is that denying the existence of material objects is a way out. But what makes it really attractive is that this denial is based on empiricist grounds: that what we perceive is only one’s own sensations and not anything “material”, so “matter” becomes no more than a theoretical posit — and, as Berkeley goes on to argue, an eminently dispensable one on the basis of Occam’s Razor.

    I would think physics is busy making this distinction moot.

  4. petrushka: I would think physics is busy making this distinction moot.

    Sure! Unless . . . wait for it . . . one accepts a purely instrumentalist conception of science itself!

    By which I mean: if a scientific theory is nothing more than a set of concepts for generating predictions about future experiences on the basis of past experiences, then accepting physical theories is fully compatible with Berkeley’s denial of the existence of material entities.

  5. I wouldn’t deny the existence of material entities. I would just say they represent layers of symmetry breaking going back to stuff that doesn’t resemble stuff. The deeper you go down the rabbit hole, the less matter looks like billiard balls and the more it looks like probabilities.

    I can’t believe I typed that. I will have to iron my hands.

  6. Kantian Naturalist:

    Sure! Unless . . . wait for it . . . one accepts a purely instrumentalist conception of science itself!

    By which I mean: if a scientific theory is nothing more than a set of concepts for generating predictions about future experiences on the basis of past experiences, then accepting physical theories is fully compatible with Berkeley’s denial of the existence of material entities.

    I think one would be hard pressed to find any successful physicist who actually believes that; it’s self-contradictory on its face.

    After all, even assuming for the sake of argument that idealism is the case, experimental procedures would still be exploring the “unknown;” and that unknown would have all the attributes of something external. The idealist – or solipsist, in the extreme – would have no choice but to behave as though there was a reality “out there” to be explored.

    What possible advantage accrues by assuming idealism when doing research? It only highlights an old theological/philosophical issue that was perhaps a part of the transition from ancient ideas to modern science, but it has little relevance today other than as a training exercise in the history of thought.

  7. Mike, I think we are saying the same thing.

    There is no self-consistent form of dualism, and there is no testable difference between mindism and physicalism or realism. Regardless of what reality really, really is, we are stuck with methodological naturalism.

  8. Mike Elzinga: I think one would be hard pressed to find any successful physicist who actually believes that; it’s self-contradictory on its face.

    If my knowledge of the history of physics is correct, some of the founders of quantum mechanics (Bohr, maybe?) were phenomenalists about experience and instrumentalists about theories.

    That’s not Berkeleyian idealism, but only because idealism is a positive thesis about the ultimate cause of sensations. The phenomenalism+instrumentalism view — which takes up a long arc in both science and philosophy of science (Comte, Mill, Mach, Avenarius, Bohr, Huxley, Carnap (early), Quine (sort of), and today the “constructive empiricism” of Bas van Fraassen — basically held that both “idealism” and “materialism” are metaphysical dogmas that have no place in scientific reasoning.

    However, to my knowledge, the only philosopher who explicitly links the whole phenomenalism + instrumentalism tradition back to its origins in Berkeley is Vladimir Lenin, in his delightful (though ultimately shallow) polemic Materialism and Empirio-Criticism (1909).

  9. petrushka: There is no self-consistent form of dualism, and there is no testable difference between mindism and physicalism or realism. Regardless of what reality really, really is, we are stuck with methodological naturalism.

    I actually think our epistemic prospects are slightly better than that. The practice of science is implicitly committed to the principle that reality has a character that does not depend on what any particular finite inquirer believes about it. The very success of science amounts to a practical vindication of this principle. As to what the character of reality is, I don’t think we have anything better than science to go on — what is real is such things as electrons, genes, ecosystems, species, neurons, etc.

  10. Kantian Naturalist: The practice of science is implicitly committed to the principle that reality has a character that does not depend on what any particular finite inquirer believes about it. The very success of science amounts to a practical vindication of this principle. As to what the character of reality is, I don’t think we have anything better than science to go on — what is real is such things as electrons, genes, ecosystems, species, neurons, etc.

    That seems about right to me. I am not as instrumentalist as you sometimes seem to believe.

  11. keiths:

    It might help if you could give a hypothetical example of an indirect perceptual system, compare it to a direct perceptual system, and highlight the relevant differences.

    Neil:

    I’m planning to do something along those lines on my own blog, over the next few days. Then I’ll mention it here (or perhaps start a new thread).

    Good. I look forward to it.

  12. Mike:

    I think one would be hard pressed to find any successful physicist who actually believes that; it’s self-contradictory on its face.

    After all, even assuming for the sake of argument that idealism is the case, experimental procedures would still be exploring the “unknown;” and that unknown would have all the attributes of something external. The idealist – or solipsist, in the extreme – would have no choice but to behave as though there was a reality “out there” to be explored.

    That’s exactly why it isn’t “self-contradictory on its face” for a scientist to accept Berkeley’s idealism (as KN and petrushka also point out).

    Under realism, reality is external to God and to us. Under Berkeley’s idealism, “reality” is internal to God’s mind (hence the quote marks), but it is still external to us. Science becomes an empirical investigation of (some of) the thoughts within God’s mind.

    What possible advantage accrues by assuming idealism when doing research?

    My answer to petrushka, who asked a similar question:

    If there are no entailments, then there is no practical difference. However, being a curious sort (in both senses of the word), I’m hoping there is an overlooked entailment that will somehow allow us to settle the question in the future. I’m rooting for realism.

    If there is no such entailment, then we’ll just have to accept that the question can’t be resolved.

    ETA: Discovering a hitherto unknown inconsistency in either idealism or realism could also resolve it. Interesting question: What would it mean if we discovered inconsistencies in both?

    Mike:

    It only highlights an old theological/philosophical issue that was perhaps a part of the transition from ancient ideas to modern science, but it has little relevance today other than as a training exercise in the history of thought.

    Its relevance lies in the fact that it might actually be true, even if most of us suspect that it isn’t.

  13. llanitedave,

    The eating of children is almost universally considered a horror, but the eating of lutefisk is only a horror in certain cultures.

    Missed that the first time!

    I evaded the horror, being raised among mostly German Lutherans, not Scandinavian ones.

  14. Kantian Naturalist: If my knowledge of the history of physics is correct, some of the founders of quantum mechanics (Bohr, maybe?) were phenomenalists about experience and instrumentalists about theories.

    The transition from classical physics to quantum mechanics was filled with bewilderment because expectations that were due to a familiarity with classical physics were being called into question. The experiments were producing new data that nobody knew how to interpret early on by just using classical physics. But I don’t believe anyone – not Bohr, not Heisenberg, not anyone that I know of – actually believed that these experiments were telling them about anything other than a real world.

    There were certainly questions about what quantities were to be taken as fundamental as well as what concepts were merely crutches to be used until fundamental quantities were nailed down; that always happens at the frontiers of research. For example, the concept of a planetary-like electron orbit was called into question; and Heisenberg opted to deal only with what experiments could measure in the form of energy differences between “atomic states.” New quantities, such as intrinsic spin, were a puzzle because they had no counterpart in classical physics.

    An entire new set of properties of particles had to be learned, but those properties were about things in an external world.

    Mach and the Logical Positivists were perhaps extreme in asserting that theories shouldn’t include things that were unobservable. Mach was pretty harsh with Boltzmann over the notion of atoms. But Mach and the Logical Positivists were wrong. One can build theories as if something were true; but the bottom line comes with an independent set of experiments and measurements that confirm the existence of those postulated entities. Theory doesn’t stop at mere postulation.

    Whether it is atoms, neutrinos, dark matter, dark energy, or any other postulated causes of observed phenomena, nothing is “written in stone” until those things are verified by some definitive experimental means. One can’t just stop at “that would explain it” or “you can’t tell the difference, so it doesn’t make any difference” The drive to do those experiments comes from the assumption that there is an external reality to be explored and an expectation that eventually it will respond to probing.

    Physicists don’t wrangle over questions such as, “Is my ‘green’ the same as your ‘green’?”; they look for measurable numbers, such as frequency and wavelength, on which agreement can be reached. That is taken to be reality; and we bootstrap from there.

  15. keiths: Its relevance lies in the fact that it might actually be true, even if most of us suspect that it isn’t.

    If it is indeed relevant, I have yet to learn of anyone taking it seriously enough to submit a research proposal for peer-reviewed funding. What experiment would one do?

  16. Mike,

    The experiments you’d do would be the same ones you’d do to show that realism is true, and the results would be equally inconclusive (which is why no one is submitting research proposals to the NSF). Both are compatible with our observations, and neither has been refuted.

    Most of us prefer realism because it fits better with our intuitions. To me it seems simpler, too, though Berkeley thought otherwise. Neither fits the evidence better, however, and to declare realism true and idealism false would be premature at best. We don’t yet have a valid reason to render that judgment.

    Instead of jumping the gun, I think we should be clear about what we do and don’t know. As I’ve said several times, it makes no practical difference at the moment. It does have the advantage of being honest, however.

  17. keiths: Instead of jumping the gun, I think we should be clear about what we do and don’t know. As I’ve said several times, it makes no practical difference at the moment. It does have the advantage of being honest, however.

    I don’t believe it is fair to conclude that physicists are being dishonest if they don’t take these “philosophical arguments” as seriously as perhaps you do. A good many of us don’t even take ourselves seriously; if one gets too uptight about the work, one’s work suffers.

    If I understand my colleagues correctly – and I think I do, because many of us have discussed these matters among ourselves over the years – most would see these arguments as “entertaining” but not to be taken too seriously or engaged in with great pomposity. Informal discussions among ourselves about experiments and theory can be quite funny and rely on a lot of inside humor offered in a deadpan manner. It takes a bit of looseness to be effective.

    Richard Feynman was being quite honest in his distain for “philosophy” because he felt much of what he saw “philosophers” doing was a complete waste of time while also misinterpreting or misrepresenting what researchers were actually doing. And Feynman was pretty good at knowing how to form answerable questions.

  18. Mike,

    I don’t believe it is fair to conclude that physicists are being dishonest if they don’t take these “philosophical arguments” as seriously as perhaps you do.

    I don’t either. Being uninterested in a question doesn’t make one dishonest. Prematurely settling on an answer, when you know it isn’t warranted, does.

    A good many of us don’t even take ourselves seriously; if one gets too uptight about the work, one’s work suffers.

    Yes, and a suffocating uptightness about which questions one is and isn’t allowed to ask is deadly to creative thinkers.

    If I understand my colleagues correctly – and I think I do, because many of us have discussed these matters among ourselves over the years – most would see these arguments as “entertaining” but not to be taken too seriously or engaged in with great pomposity.

    Arguments can be dismissed with as much pomposity as they are offered. A little humility can go a long way on both sides.

    Informal discussions among ourselves about experiments and theory can be quite funny and rely on a lot of inside humor offered in a deadpan manner.

    Every field has its inside jokes, including philosophy.

    Richard Feynman was being quite honest in his distain for “philosophy” because he felt much of what he saw “philosophers” doing was a complete waste of time while also misinterpreting or misrepresenting what researchers were actually doing.

    There’s good philosophy and bad philosophy, good science and bad science. The good kinds are worthwhile, and the bad kinds are a waste of time. Some bad philosophers misinterpret or misrepresent what scientists do, and some bad scientists misinterpret or misrepresent what philosophers do.

    The battle we should be fighting is between good thinking and bad thinking, not between philosophy and science.

    And Feynman was pretty good at knowing how to form answerable questions.

    God help us (so to speak) if we ever start deciding prematurely and for all time which questions are unanswerable — and proceed to ignore them.

  19. keiths:

    Descending from “light” to “photons” doesn’t obligate me to descend from “I” to “the collection of atoms commonly known as ‘keiths’”.

    I don’t really have anything useful add to the ideas that KN put forward which I am still grappling with so I won’t try to reply to this.

    One of the challenges I find in these forum discussions is that sometimes conversations end for no apparent reason — did one say something stupid, irrefutable or has it become too tedious to continue? Or has the other person nothing more of value they want to say (as for me, here).

  20. BruceS,

    Level-switching isn’t always appropriate — it would be silly to describe Gwyneth and Chris’s split in terms of particle physics, when psychological explanations are available — but that doesn’t mean that level-switching is verboten.

    “Orangutans eat fruit” and “orangutans metabolize sugar” are both legitimate statements.

  21. keiths:
    Level-switching isn’t always appropriate — it would be silly to describe Gwyneth and Chris’s split in terms of particle physics, when psychological explanations are available — but that doesn’t mean that level-switching is verboten.

    Am I being intellectually baited to continue (grin)?

    Here is the issue that vexes me. I want to use an analogy to music, even though I know it is far from perfect.

    Performed music supervenes on the physical nature of sound waves. Now consider these two statements about a selection from a performance:
    1. That passage of music contains notes of high frequency.
    2. That passage of music contains ideas that occur with high frequency in music from that period.

    Obviously “high frequency” means two entirely different things in these two statements.

    Now when KN says “direct perception of the world”, I get confused because I think that perception is far from direct because there is all that electrochemical processing starting from the retina and continuing through networks of neurons (and that ignores how the photons got to my retina in the first place). How can that be called direct?

    But maybe his use of “direct perception” in that context means something entirely different here from how I am interpreting it. Further, what gives the phrase “direct perception” meaning and the conditions that make it true are not the types of things I am thinking of. For example, I understand KN’s concern with Sellars ideas on scientific realism being “more true” in this way.

    My challenge is that I feel confident talking about the scientific interpretation but not confident at all about the other possibilities.

  22. BruceS,

    Am I being intellectually baited to continue (grin)?

    Yes. 🙂

    But maybe his [KN’s] use of “direct perception” in that context means something entirely different here from how I am interpreting it.

    Earlier, KN:

    1) drew a distinction between “epistemic mediation” and “causal mediation”,

    2) argued that at the “personal level” there is no epistemic mediation between the perceiver and the thing being perceived, so that perception at that level is direct perception; and

    3) argued that at the “subpersonal level” there is causal mediation, so that perception at that level is indirect perception.

    My response:

    You perceive that they’re green, but I would argue that you don’t perceive it directly. After all, you don’t interact directly with the leaves, you interact with the photons reflected from them. (Note that is as true at the “personal” level as it is at the “subpersonal”.) If someone were to create and direct an identical stream of photons into your eyes (with a hologram, say), you would still perceive green leaves even if there were no leaves there at all.

    This is not just a quibble, because it shows that there really is “epistemic mediation” between you and the leaves. And not just the photons themselves, but your assumptions about their provenance (that they are not coming from a hologram, for example).

  23. keiths:

    Off-topic: There is a Centre for Cosmology, Particle Physics and Phenomenology at the Catholic University of Louvain.

    Either “phénoménologie” means something quite different in French, or their departmental meetings must be really interesting.

    Phenomenology has a very distinct meaning in physics. It is a stage of modeling and exploration that looks only at relatively easily accessible phenomena and expresses preliminary mathematical relationships among phenomena in those terms. This comes before delving into the details of postulated entities that may be a more fundamental cause of those phenomena.

    For example, classical thermodynamics is a phenomenological set of laws relating things like temperature, volume, pressure, magnetization, etc. of a system. Later we discovered that atoms and their quantum mechanical rules turn out to be more fundamental by collectively generating those phenomenological relationships.

    Another simple example is curve fitting to a set of data. One can, for example, make resistance thermometer by fitting an nth degree polynomial to a set of resistance versus temperature data, where the temperature is measured by some other device that defines temperature. One doesn’t have to know the underlying details about how the resistance is affected by temperature; one needs only a phenomenological paring of two sets of numbers to which a mathematical curve can be fit. In the case of a resistance thermometer, one would like a monotonic curve.

    One can use phenomenological relationships (phenomenology) for many things without understanding the details of why those relationships are what they are. They can be correlations that are useful for calibration or for measurement. They can be fiducial markers that indicate the same conditions are in existence in an experiment. They can be whatever one likes as long as they are repeatable and reliable indicators of the state of a system.

    The reason for this business of phenomenology is to search out mathematical relationships and curves that await later theoretical underpinnings that predict those relationships and curves. The mathematics of the more fundamental theory may not look anything like the mathematics of the fitted curves, but they will produce curves that are very close to the phenomenological relationships.

    So, again as an example, the resistance of various types of semiconductors and metals as a function of temperature is explained by solid state theory which uses quantum mechanics and the properties of atoms and molecules to explain the properties of solids. Resistance (conductance) is explained in terms of binding energies, band gaps, and carrier mobility within the solids; and there is often a competition between mobility and binding because of carrier scattering by lattice vibrations (phonons). Some of the tests of the underlying theory are done by comparing what the more detailed theory predicts with the phenomenological relationships.

    In short, phenomenology in physics is a temporary stepping stone to more detailed theories.

  24. I’m tyring to understand KN’s point of view at the same time as I apply it to your points, but with that caveat….

    keiths: . (Note that is as true at the “personal” level as it is at the “subpersonal”.)

    That is the one point where I am unsure. Does the meaning of “true at the subpersonal level” mean the same thing as “true at the personal level”? Until that is determined, this statement is undecided for me.

    You ignored my example about “high frequency”, probably out of mercy for my intellectual self esteem, but since I don’t know if I am in a hole yet, I will keep digging.

    To understand whether a series of notes has high frequency in the first sense, you’d need to understand what frequency is for sound waves, how to do eg spectral analysis, what would constitute a high frequency for the human ear. Then you could assess the truth of that first statement.

    To understand high frequency in the second statement, you’d need to understand what a musical idea was, how to find the musical ideas are in the passage, what musical ideas were common in that period, how to compare musical ideas.

    Further, suppose you asked a musical expert what the musical idea was that was common, and he said it was that the music had “soul”. He added that this was something that all of his expert colleagues agreed on but which could not be reduced to mere technical analysis of sounds.

    Does the same type of non-reducibility apply to the perception question?
    ETA: This example is meant to show how I understand KN’s point about normative aspects of reducibility, meaning, and truth. A child can be right or wrong about something being green, but light frequencies simply are what they are.

    I could go on to give a Chinese Room analogy, but that’s probably taking it too far!

    This is not just a quibble, because it shows that there really is “epistemic mediation” between you and the leaves. And not just the photons themselves, but your assumptions about their provenance (that they are not coming from a hologram, for example).

    I think KN left himself an out for this by sayng that direct perception was still subject to empirical inquiry. And if you think that seems to contradict some of what I say above, well, I agree. But I am not ready to say that that makes KN inconsistent (or better my interpretation of KN). I just don’t understand it well enough.

  25. Mike,

    Phenomenology has a very distinct meaning in physics. It is a stage of modeling and exploration that looks only at relatively easily accessible phenomena and expresses preliminary mathematical relationships among phenomena in those terms. This comes before delving into the details of postulated entities that may be a more fundamental cause of those phenomena.

    In that case the scientific and philosophical meanings are actually quite similar. In both cases we are dealing with things as they appear to us, independent of the underlying reality.

    It’s just that in the philosophical context, ‘appearance’ is purely a first-person thing, while in scientific phenomenology it can refer to objective observations shared by a community of observers.

  26. Interesting use of “phenomenology”. So it’s not an answer to, “what is it like to be boson?”

    I think I caused more problems that I intended to — and were necessary — by not clarifying what I meant by “epistemic intermediaries”, in contrast with “causal intermediaries.”

    By “epistemic intermediaries,” I mean anything inferential or rational. Someone who believes in “sense-data” (here I’m thinking of Russell) would have to say — rationally reconstructing — “I am directly perceiving sense-data of XYZ type, and I have no reason to believe I am hallucinating, am being tricked by an evil genius, etc., so I infer that there is an actual XYZ which is the cause of my sense-data.” The occurrence of sense-data is taken as a premise which has, as its inferentially mediated conclusion, an assertion about physical reality.

    Now, my claim that perception is “direct” is intended only against the sense-data theorist — someone who thinks that assertions about physical objects with sensible features are the conclusions of inferential processes. In other words, it is only epistemic intermediaries to which I am objecting.

    But that is consistent with also holding that there are all sorts of causal intermediaries, to which keiths has been drawing our attention — what’s going with the photons, how the cones in my retina fire in response to them, and so on. (I think this clarification about how I understand the difference between “epistemic intermediaries” and “causal intermediaries” actually makes our views consistent with one another.)

    If Keiths were to disagree, it might be because — as he rightly emphasizes — my perception of the green leaves is, in another sense, mediated by all sorts of assumptions and beliefs about the world: that there are physical objects that endure through Space and Time, that some of them have perceptible features, that these features are perceptible by other perceivers besides myself.

    In all these respects, my direct perception of the green leaves is indeed mediated by my conceptual framework! And — one might continue to press the objection — if that’s not epistemic mediation, then what is it?

    The contrast I want to insist on here is the distinction between

    (1) how my conceptual framework mediates my perceptually taking in of the leaves and their greenness

    and

    (2) the sense-datum theorist’s inferential move from his or her leaf sense-data and green sense-data to positing the existence of green leaves as the consequence of his or her inferential activity.

    I agree with keiths about (1), but since I deny that there are epistemic intermediaries in the sense of (2), perception at the personal-level of description is “direct”.

  27. Kantian Naturalist: I agree with keiths about (1), but since I deny that there are epistemic intermediaries in the sense of (2), perception at the personal-level of description is “direct”.

    This might be a helpful analogy from the actual history of trying to quantify a perception.

    Different kinds of “thermometers” (once called thermoscopes) have different responses to “degrees of heat.” These would be analogous to the structural differences you refer to as “conceptual framework.”

    Newton used the colors of various familiar heated objects as well as when waxes and ice melted. Many things expand when heated; e.g., wine or mercury in a glass tube. Galileo use wine, Fahrenheit introduced mercury. The length of the column was marked off in “degrees of heat;” corresponding to what we might refer to as the “in-your-faceness” of a hot object.

    Other materials have other responses; e.g., the resistance of a piece of metal, the voltage across a thermocouple junction, the color of a particular kind of assembly of molecules. One can make a longer list, but these will do.

    Once one decides on the phenomenon and the values to be assigned to the “output” of the device that produces the phenomenon, one defines temperature, a concept that now becomes a quantified attribute or quality of bodies that were perceive by our bodies as hot, warm, or cold.

    Looked at from that perspective, our nervous systems are “transducers” that make roughly qualitative – and partially quantitative – responses to bombardments from the surrounding environment. Our “perceptions” – which are possible because the complexity of our nervous systems allows for memories and memories of memories – are the form of detection that is analogous to any other kind of transducer that can measure the same phenomenon. So in the case of heat, we are “thermometers” that sense the energy outputs of surrounding objects.

    The link between “sensation” or “transducer output” and hotness becomes what we call “temperature;” and, in the case of many systems such as expanding columns of mercury or resistors, it is quantifiable. Our nervous systems are not very precise at quantifying heat, but other senses do a little better at quantifying other forms of incoming energy such as sound or light or mechanical work.

    It is easier to see the connections if one starts with very simple biological systems that respond minimally to heat, light, or chemical gradients, and then works on up the ladder of complexity to the nervous systems of animals.

    So our systems are responding directly to external input in the way that their construction allows them to respond. Unfortunately we don’t expand linearly with increasing amounts of incoming energy, so we aren’t very good “thermoscopes” in the quantitative sense.

  28. Kantian Naturalist: Now, my claim that perception is “direct” is intended only against the sense-data theorist — someone who thinks that assertions about physical objects with sensible features are the conclusions of inferential processes. In other words, it is only epistemic intermediaries to which I am objecting.

    Another point concerning this specific objection.

    Why would inferences be temperature dependent? If the nervous system works only within a rather narrow energy range of a few hundredths of an electron volt, why is that not evidence that it is in contact with a real (not-inferred) world.

    The ability to infer comes with the complexity of the nervous system and the existence of memories of things experienced. To then extrapolate to the notion that one infers the existence of causes of our sensations seems a bit excessive if it is carried beyond recent memories of what to do about particular “signals” one is getting at the moment (is that a cheetah in the grass?)

    Knowing what we do about the evolution of living systems, it is more likely that systems that respond directly to the environment would have the best chances of adapting to those environments through reproduction. Systems that have insufficient capability or complexity to “infer” are perfectly capable of adapting through natural selection. Those living systems with responses that “lie” or have excessive delays in their responses will tend to be driven to extinction.

  29. Mike Elzinga,

    I don’t really disagree with what you say here, Mike. It’s perfectly clear that the brain, as a physical object, conforms (and must conform) to the laws of physics (and other laws of nature).

    The question I’m wrestling with is whether it makes sense to say that and yet also, at the same time, distinguish between the third-person explanations of the brain and the body-environment causal nexus within which the brain is embedded and the first-person understanding of the rational animal or person whose brain it is.

    And, I should add, to accept that distinction between perspectives — the third-person explanation and the first-person understanding — in such a way as to avoid giving aid and comfort to dualism (or idealism).

  30. Kantian Naturalist: The question I’m wrestling with is whether it makes sense to say that and yet also, at the same time, distinguish between the third-person explanations of the brain and the body-environment causal nexus within which the brain is embedded and the first-person understanding of the rational animal or person whose brain it is.

    Yes, I believe that makes sense. Or, at least, it makes sense to me.

  31. Kantian Naturalist: The question I’m wrestling with is whether it makes sense to say that and yet also, at the same time, distinguish between the third-person explanations of the brain and the body-environment causal nexus within which the brain is embedded and the first-person understanding of the rational animal or person whose brain it is.

    Well, I suspect the short answer to that is memory; more specifically, hierarchies of memory that feed each other and record our sensory inputs. Memories include our internal experiences of ourselves, and hierarchies of memory allow the building of experience along with memories of our changing selves; and thus a running profile of ourselves.

    Mix that with constant sensory input, and such hierarchies of memory produce the relationship between our first-person self and the third-person understanding of our connection to the physical world; no dualism required.

    I leave early tomorrow morning on a trip for the next week or so; and I don’t know if I will have access to a computer.

  32. KN,

    The contrast I want to insist on here is the distinction between

    (1) how my conceptual framework mediates my perceptually taking in of the leaves and their greenness

    and

    (2) the sense-datum theorist’s inferential move from his or her leaf sense-data and green sense-data to positing the existence of green leaves as the consequence of his or her inferential activity.

    I agree with keiths about (1), but since I deny that there are epistemic intermediaries in the sense of (2), perception at the personal-level of description is “direct”.

    Again, you seem to be contradicting yourself. Above you identify direct perception by the absence of inference, but earlier in the thread you did just the opposite:

    I’m going to leap right onto the grenade you’re dangling out in front of me and deny the obvious: that we perceive the motion yet there is none in reality. Instead, I’m going to say that what we directly perceive is the unreality of the motion that we sense, or put otherwise, the unreality of the apparent motion — that the sensed motion is only apparent.

    Here the ‘direct perception’ of the absence of motion depends on an inference.

    I’ll assume for now that you reject your earlier statement and that your latest statements reflect your current view, but please confirm.

  33. keiths:
    Mike,

    The experiments you’d do would be the same ones you’d do to show that realism is true, and the results would be equally inconclusive (which is why no one is submitting research proposals to the NSF).Both are compatible with our observations, and neither has been refuted.

    Most of us prefer realism because it fits better with our intuitions.To me it seems simpler, too, though Berkeley thought otherwise. Neither fits the evidence better, however, and to declare realism true and idealism false would be premature at best.We don’t yet have a valid reason to render that judgment…..
    Kantian Naturalist,

    Kantian Naturalist:
    Interesting use of “phenomenology”. So it’s not an answer to, “what is it like to be boson?”

    I think I caused more problems that I intended to — and were necessary — by not clarifying what I meant by “epistemic intermediaries”, in contrast with “causal intermediaries.”

    By “epistemic intermediaries,” I mean anything inferential or rational.Someone who believes in “sense-data” (here I’m thinking of Russell) would have to say — rationally reconstructing — “I am directly perceiving sense-data of XYZ type, and I have no reason to believe I am hallucinating, am being tricked by an evil genius, etc., so I infer that there is an actual XYZ which is the cause of my sense-data.” The occurrence of sense-data is taken as a premise which has, as its inferentially mediated conclusion, an assertion about physical reality.

    Now, my claim that perception is “direct” is intended only against the sense-data theorist — someone who thinks that assertions about physical objects with sensible features are the conclusions of inferential processes.In other words, it is only epistemic intermediaries to which I am objecting.

    But that is consistent with also holding that there are all sorts of causal intermediaries, to which keiths has been drawing our attention — what’s going with the photons, how the cones in my retina fire in response to them, and so on.(I think this clarification about how I understand the difference between “epistemic intermediaries” and “causal intermediaries” actually makes our views consistent with one another.)

    If Keiths were to disagree, it might be because — as he rightly emphasizes — my perception of the green leaves is, in another sense, mediated by all sorts of assumptions and beliefs about the world: that there are physical objects that endure through Space and Time, that some of them have perceptible features, that these features are perceptible by other perceivers besides myself.

    In all these respects, my direct perception of the green leaves is indeed mediated by my conceptual framework!And — one might continue to press the objection — if that’s not epistemic mediation, then what is it?

    The contrast I want to insist on here is the distinction between

    (1) how my conceptual framework mediates my perceptually taking in of the leaves and their greenness

    and

    (2) the sense-datum theorist’s inferential move from his or her leaf sense-data and green sense-data to positing the existence of green leaves as the consequence of his or her inferential activity.

    I agree with keiths about (1), but since I deny that there are epistemic intermediaries in the sense of (2), perception at the personal-level of description is “direct”.

    I

    These are really interesting posts, covering lots of territory very thoughtfully. My own sense is that there not only is but must be some sort of perception that has no epistemic intermediaries, that empiricism requires those sorts of “raw feels.” The problem is that nothing can be said about them, not even Chisholmian “being appeared to greenly” because at that point we already ARE blending in things from our language, stuff we’ve learned, etc. So we’re in the area of the ineffable.

    I’m comfortable in that (Tractarian, Schlickian) place myself, but I think it suggests part of the reason it’s not a scientific area. It’s, to put it mystically, outside the realm of what can be investigated more accurately, beyond what “can be said.” It’s my view that we can’t get to the bottom of these philosophical questions by the building of better equipment or the designing of better experiments.

    W

  34. walto: I’m comfortable in that (Tractarian, Schlickian) place myself, but I think it suggests part of the reason it’s not a scientific area.

    Wittgenstein is one of those philosophers who generate a lot of humorous quips from physicists.

    It has been said that, “Anyone who claims to understand Wittgenstein doesn’t understand Wittgenstein.” 🙂

    (Heading off for travel now.)

  35. Kantian Naturalist: On the other hand, if one rejects the Cartesian conception of mind, then Berkeley’s views just don’t even get their way out of the gate.

    Exactly, which is why, I suspect, Johnson didn’t waste too much time on refining his refutation. 🙂

  36. walto:

    “Anyone who claims to understand Wittgenstein doesn’t understand Wittgenstein.”

    Not much danger of such a claim from me, fortunately. In the immortal words of Woody Allen, “I don’t even know how this can opener works.”

    W

  37. walto: My own sense is that there not only is but must be some sort of perception that has no epistemic intermediaries, that empiricism requires those sorts of “raw feels.” The problem is that nothing can be said about them, not even Chisholmian “being appeared to greenly” because at that point we already ARE blending in things from our language, stuff we’ve learned, etc. So we’re in the area of the ineffable.

    I’m comfortable in that (Tractarian, Schlickian) place myself, but I think it suggests part of the reason it’s not a scientific area. It’s, to put it mystically, outside the realm of what can be investigated more accurately, beyond what “can be said.” It’s my view that we can’t get to the bottom of these philosophical questions by the building of better equipment or the designing of better experiments.

    Lately I’ve been doing a lot of work on C. I. Lewis, which is itself fairly unusual for someone my age. (I received my Ph.D. in 2005.) I’m trying to reconstruct the debates around Lewis, Reichenbach, Morton White, Nelson Goodman, and Quine. All this feeds directly into how Sellars influenced Rorty, Brandom, McDowell, and Haugeland.

    I now think that the very heart of all these problems arises from a fundamental error that conflates what I call “transcendental friction” with passivity. By ‘transcendental friction,’ I mean the demand for a guarantee that our thoughts, when true, are in touch with a reality that is not constituted by those thoughts, such that we can make sense of the idea of objectivity — that our thoughts can succeed or fail in getting at the world correctly.

    Now, it seems to me that the majority of philosophers in this analytic/pragmatist tradition have thought that if there is any objectivity, then it must lie in receptivity — how we are passively affected by objects. So we can meet the demand for transcendental friction only if we can locate a region of experience to which our thought makes no contribution. (This is how Lewis defines “the given”, and it’s why Lewis concludes that the given is ineffable.)

    The error here is complicated — an over-reliance on vision and color as paradigms of perception; an under-appreciation of the role of embodiment in perception; lack of appreciation of the role of embodied skills; lack of appreciation of the social and historical structure of justification (owing to an illicit privileging of a model of justification drawn from formal domains — logic and mathematics — over attention to the dynamics of justification in substantive domains, such as empirical inquiry, science, ethics, and so on); an over-intellectualization of what counts as “conceptual activity.”

    The alternative to these errors, as I now see it, involves recognizing that it takes a tremendous amount of skill, discipline, theorizing, attention, and focus in order for the world to get a vote in what we say about it. The world does get a vote in what we say about it (contra the worst of postmodernism), and it does so not on account of our passivity (as both empiricists and rationalists held) but on account of our activity (as the best of the pragmatist tradition holds).

  38. Kantian Naturalist: Now, it seems to me that the majority of philosophers in this analytic/pragmatist tradition have thought that if there is any objectivity, then it must lie in receptivity — how we are passively affected by objects. So we can meet the demand for transcendental friction only if we can locate a region of experience to which our thought makes no contribution. (This is how Lewis defines “the given”, and it’s why Lewis concludes that the given is ineffable.)

    Not being a professional philosopher, I can’t comment on what’s in the tradition. But I think you are completely correct in seeing this as error. Worse still, it doesn’t even work. Berkeley’s idealism shows that this receptivity doesn’t guarantee what it is supposed to guarantee.

    In studying human learning, I looked to science for examples. And it seemed to me that science could not work if it were merely receptive. The laboratory, in which we probe and test features of reality, is fundamental to science. And, likewise, I believe that our probing and testing the world is fundamental to us at the personal level, in how we acquire knowledge of the objective world.

    If our knowledge is such as can only be acquired by probing and testing, and could not be acquired as passive receivers, then I see that as our best guarantee that there is indeed an objective reality.

  39. Neil,

    If our knowledge is such as can only be acquired by probing and testing, and could not be acquired as passive receivers, then I see that as our best guarantee that there is indeed an objective reality.

    You’re misunderstanding Berkeleyan idealism if you think it renders us “passive receivers”. I addressed this earlier in the thread:

    No, because under idealism one can still move around, poke, prod, taste, sniff, and lay one’s ear on the tracks. It’s just all happening in what is effectively a virtual reality.

    It’s quite similar to the brain-in-a-vat scenario, except that with the envatted brain, there is still an external reality — just not the one you think is out there.

  40. Welcome to TSZ, walto.

    You write:

    These are really interesting posts, covering lots of territory very thoughtfully. My own sense is that there not only is but must be some sort of perception that has no epistemic intermediaries, that empiricism requires those sorts of “raw feels.”

    That’s true if you’re speaking of conscious epistemic intermediaries, as I think KN was. If so, then I predict you won’t get much of an argument from anyone. When I see my friend’s face, I immediately perceive it as a face, and as her face, without any conscious deliberation. I don’t have to work my way through a list of features, checking off the ones that match, as some poor souls with prosopagnosia do. The recognition is instant and arguably pre-conscious, but that doesn’t mean there isn’t a hell of a lot of processing going on “under the hood”.

    The actual academic debate about direct perception seems to revolve around this subconscious or pre-conscious processing. As far as I can tell from my limited reading on the subject, diirect perception theorists think that there is very little processing, that what processing there is proceeds in a bottom-up fashion, and that the perceived objects are not modeled.

    The problem is that nothing can be said about them [“raw feels”], not even Chisholmian “being appeared to greenly”…

    You just said something about them. 🙂

    It’s my view that we can’t get to the bottom of these philosophical questions by the building of better equipment or the designing of better experiments.

    I think the study of illusions can tell us a lot about what’s going on under the hood. The motion illusions I linked to are quite revealing, and they show that motion (at least in these cases) is inferred, not directly perceived.

  41. keiths:

    The actual academic debate about direct perception seems to revolve around this subconscious or pre-conscious processing.As far as I can tell from my limited reading on the subject, diirect perception theorists think that there is very little processing, that what processing there is proceeds in a bottom-up fashion, and that the perceived objects are not modeled.

    It’s probably dangerous to try to speak for direct realists generally, but my sense is that the epistemic intermediaries they deny aren’t so much matters of “processing” but intermediate objects of thought. I try to define this “inappropriate” epistemic intermediateness in my paper “The Rise and Fall of Disjunctivism” which can be found here: http://www.scribd.com/doc/162228185/Rise-and-Fall-of-Disjunctivism-Horn

    I don’t know much about the actual processing (any more than I know about the can opener). I guess somebody could complain that I’m hiding under my desk, since my views generally take the form “if you can learn about it in a science class, I’m not talking about that.” But I’m also willing to concede that none of these metaphysical (because not scientific) positions are provable one way or the other. I basically revert to Carnapian pragmatism about the “external questions.”

    Re my Chisholm-style remark, you’re right that I can say THAT, but those kinds of statements have already got reality categorized. We could insist that that’s all there is–there just isn’t any non-categorized world. But I think that way leads to idealism. I take the position that there’s this really narrow reed (almost a Medieval pin!) that any supportable empiricism has to dance on: if either the “feels” aren’t completely raw or don’t exist at all, bye-bye empiricism, hello Bradley.

    I get, though, that it’s an uncomfortable place to stand and that, e.g., Sellars left it for more comfortable, “scientific” upholstery.

    W

  42. walto: We could insist that that’s all there is–there just isn’t any non-categorized world. But I think that way leads to idealism. I take the position that there’s this really narrow reed (almost a Medieval pin!) that any supportable empiricism has to dance on: if either the “feels” aren’t completely raw or don’t exist at all, bye-bye empiricism, hello Bradley.

    I think that it is almost exactly right. That’s certainly how C. I. Lewis saw it — the purpose of “the given” is precisely to rescue minimal empiricism from Bradley-style idealism. And that’s the problematic that Lewis passed onto the next generation of titans: Firth, Sellars, Goodman, White, and Quine.

    Even Sellars was sympathetic to this line of thought; in Science and Metaphysics he wrote:

    Indeed, it is only if Kant distinguishes the radically non-conceptual character of sense from the conceptual character of the synthesis of apprehension in intuition … and accordingly, the receptivity of sense from the guidedness of intuition that he can avoid the dialectic which leads from Hegel’s Phenomenology to nineteenth-century idealism. (Science & Metaphysics, p. 16, I.40)

    So even Sellars, the great foe of the Given, thinks that we need to recognize the distinction between conceptual activity and the non-conceptual (hence non-intentional) character of sensations, or what he calls “sheer receptivity” (with no spontaneity mixed in with it).

    But, as I’ve now been thinking, this entire strategy is mistaken. What we want, if we want to avoid any sort of idealism, is ‘transcendental friction’: we want some guarantee that our perceptions are able to constrain our judgments because perceptions disclose features of non-mental reality. (Here I’ve been thinking a lot lately about Royce’s “argument from error” for absolute idealism, where he argues that perceptions are able to correct judgments because the perceptions are themselves already judgments contained within an infinite mind.)

    But it does not follow that transcendental friction requires any commitment to the passivity of sense. This is just an assumption that everyone has, but it’s strictly optional. What animates this assumption is the further commitment that the conceptual is the intentional. Only if one accepts this commitment would it then seem that if, we want to show from within the standpoint of experience that there is a constraint on judgment, that constraint must be non-conceptual and therefore non-intentional, and hence purely passive.

    This assumption frames the entire tradition of mid-20th century “analytic pragmatism” (what happens when American pragmatism and logical positivism collide), but we have very good reasons to think it is false, if we look across the Pond to German and French phenomenology. There, especially in the later Husserl, in Heidegger, and above all (I think) in Merleau-Ponty do we find an rich, sophisticated method for showing that there is non-conceptual intentionality, if “conceptual” is taken here to mean “the sorts of things that function in judgments and inferences.” To clarify matters somewhat, I call this “non-discursive intentionality”, and in particular, I want to focus on Merleau-Ponty’s thought that the most important kind of non-discursive intentionality is somatic intentionality.

    So my thought is that somatic intentionality can be the constraint on discursive intentionality that we need in order to avoid the slippery slope to idealism without abandoning the transcendental project entirely. And that, in a nutshell, is what my book-in-progress is all about.

  43. Kantian Naturalist: But, as I’ve now been thinking, this entire strategy is mistaken. What we want, if we want to avoid any sort of idealism, is ‘transcendental friction’: we want some guarantee that our perceptions are able to constrain our judgments because perceptions disclose features of non-mental reality. (Here I’ve been thinking a lot lately about Royce’s “argument from error” for absolute idealism, where he argues that perceptions are able to correct judgments because the perceptions are themselves already judgments contained within an infinite mind.)

    I’m not familiar with most of the philosophy that you reference. But, as best I understand it, that is about right.

    Let me try my hand at describing the problem.

    If there is a mountain that is completely smooth, we will have difficulty climbing it. But if there are some niches and crags that we can use as footholds and handholds, we may be able to scale that mountain. It might be that I use very different footholds and handholds than you use. But we will still be climbing the same mountain and we will recognize that.

    What we need for perception, is something like the footholds and handholds. And it doesn’t matter if we each do that a little differently. We use those to grasp reality. It’s okay if the way that I grasp reality is a little different from the way that you grasp reality. It is still the same reality, and we will recognize that.

    The mistaken view is that there is some fixed set of footholds and handholds, and that we must all use the same ones. Knowledge is a construct, precisely because we each have to find our own handholds and footholds to connect it to reality. And there can be no general account of intentionity that is fully detailed, because our individual intentionality depends on our individual choices of handholds and footholds. The best account we can give, is an account of how we each go about finding our own connections to reality.

  44. Neil Rickert,

    I like all that! The only major point on which we disagree is that I think there are real handholds and footholds — that reality is composed of things and not just stuff — such that we can discover through our experience of things that our categorizations have gotten the world wrong. So I’m invested in just a tad more realism than you are.

  45. walto:

    It’s probably dangerous to try to speak for direct realists generally, but my sense is that the epistemic intermediaries they deny aren’t so much matters of “processing” but intermediate objects of thought.

    Again, if you are talking about conscious intermediates, you won’t get an argument from me (or anyone else, I suspect). When I see my friend’s face, the recognition is immediate — I perceive it as hers, with no conscious inference or intermediates required.

    However, I don’t think your views are representative of those of most “direct perceptionists”. (If they were, then direct perception wouldn’t be a controversial stance.)

    This excerpt from an online book entitled Direct Perception is more typical:

    James Gibson and those who follow his approach adopt an ecological stance: they believe that perceiving is a process in an animal-environment system, not in an animal. Proponents of the ecological view argue that perception is, quite simply, the detection of information. This approach is labeled direct because a perceiver is said to perceive its environment. Knowledge of the world is thought to be unaided by inference, memories, or representations. Conversely, a second family of theories conceives of perception as mediated — or, to contrast it with Gibson’s theory, indirect — and is so called because perception is thought to involve the intervention of memories and representations.

    Direct perception cannot explain the motion illusions I cited earlier. There is no actual motion in those cases, so the motion we see is the result of inference, not direct perception.

  46. keiths:
    I don’t think your views are representative of those of most “direct perceptionists”.(If they were, then direct perception wouldn’t be a controversial stance.)

    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. I have found SEP helpful, especially the sections on sense data, disjuntivism and direct realism, eg Direct Realism and Disjunctivism and Disjunctivism.

    This article on Merleau Ponty provides an overview of one source of KN’s approach, although it is tough slog for a philosophical layman like me.

    KN has also mentioned at one point that he opposes philosophers who think epistemology can be completely subsumed by (ie naturalized through) cognitive sciences, such as the psychological theory of direct perception. So I still believe his discussion of “inference” refers to the philosophical context of first person perspective in the philosophical theories of how to decide when knowledge is correct (eg real or illusion) as opposed to the scientific problem of how understand the causal chains of events in both situations. It seems like a type of is/ought distinction to me.

    One way to bring the philosophical and scientific approaches to together might be by using a reliabilism approach to epistemology and using science to detail the source of reliability. But I don’t think that is how KN approaches it.

    I’ll look forward to the fireworks show in Neil’s thread when you have time to comment. I may give him something to warm up with. Or maybe I’ll just make some pop corn and wait.

  47. Kantian Naturalist: So I’m invested in just a tad more realism than you are.

    You are likely mistaken about that. You are reading something into it that was not intended. My point was to emphasize our role in how we see the world.

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