Neutral Monism

Neutral monism has a fascinating history, from Mach and Chancey Wright (b. 1830 in Northampton MA, where I happen to live) through William James, the American New Realists, including E.B. Holt and Ralph Barton Perry, many of them very much Harvard figures, Bertrand Russell, from 1919 to 1927, to Moritz Schlick and A.J. Ayer.

There is a slightly overlooked aspect to the view that fits in with the post-Hegelian preoccupations of the time. Here are a few lines from Chauncey Wright’s Philosophical Discussions:

Our own mind is not “first known as a phenomenon of the subject ego, or as an effect upon us of an hypothetical outward world, its first unattributed condition would be, by our view, one of neutrality between the two worlds.” Rather, “The distinction of subject and object becomes … a classification through observation and analysis, instead of the intuitive distinction it is supposed to be by most metaphysicians.”

The neutral monist wants us to start with neutral data, some of them having to do with the objects of sense, such as colors and sounds and so on. But also included by neutral monists such as Mach are times and pressures! This sounds odd, but it is really a testament to Mach’s powerful philosophical naiveté. The naive approach paid off well for him in science too, and he was sensitive to things that other researchers missed or did not notice. An example is Mach bands. Mach’s photography of the shock wave shows the same cheerful empirical spirit. Another fine example is the difference in appearance of shapes under rotation. An eighth rotation of a square makes the horizontal distance across the square narrower, so that what is a perceived is more of a diamond than a square.

What did this approach do for the mind-body problem? Take as an example a neutral item the color that I see, like the pale green (a very New England colour) of the door to my left. Is this color physical or psychological? It is hard to say. The natural thought is that the color is paint, so that what you buy at the paint shop are colours. On the other hand what color you see is determined by all sorts of things having to do with the psychology and physiology of the one who is looking at it. The answer of Mach and the other neutral monists was that pro tem a colour is neither physical nor psychological. Asking which it is is a bit like asking whether I am looking at the first, or second or third. An object becomes the first or second or third only by being put in some sort of order, and, according to the neutral monists, though the neutral data such as colours retain their neutral character come what may, in one series of things they can be regarded as physical (for example in connection with the action of light on the coloured surface) and in another they can be regarded as psychological (for example the saturation of colours is often different in the left and right eye).

So where does this get us?  Russell, rather surprisingly, having said that physical and psychological items are distinguished “only by their causal laws” (this is in “On Propositions”) allows that unperceived material things obey only physical laws, images obey only psychological laws, and sensations obey or can obey both. So for Russell during this period sensations are the only genuinely neutral elements. His view then is a sort of sandwich, with the genuinely neutral elements only in the middle. Yet if thoughts do not obey physical laws and unperceived material things obey only physical laws, how is this a genuinely neutral monism?

I have tried to give an account in The Mind-Body Problem of the way in which the neutral monist deals with causal relations between mind and body. The neutral monists seem not to have been struck by this problem, contenting themselves with naturalistic dithyrambs about the oneness of things. But that does not tell you how a puncture in the stomach lining will give you the pain of the ulcer.  What seems to me very significant is the overlap of two elements in the two different cases, here a searing. The pain is a searing one, but what the stomach acids do the lining of the stomach is searing too. Searing is something that can take a physical or psychological interpretation, and that is very interesting. The fiery aspect of searing can be seen physically on inspection of the ulcers. In connection with this sort of example I offer an account in the book of what causal relations must be for the neutral monist – I hope that readers will find it interesting.

I am also naturally very interested in the way in which images can turn into sensations. If we could get a grip on this, we would be able to understand the way in which a mental image could have an effect on the body. It is also very interesting that thoughts can become images, and the other way round, in hypnopompic and hypnogogic imagery at the borders of sleep.

A few words, as promised, about the difference between neutral monism and double aspect theories. Neutral monism has categorically physical things and categorically mental things in its ontology. If something is physical, and not psychological, it cannot be placed in a psychological series. With the double aspect theory, however, something can be viewed either as physical or as mental, either as extension or as consciousness, or whatever the “principle attributes” of matter and mind are. This difference between the two theories has an important corollary. With neutral monism there is psychophysical causation, as with interactionist dualism, but not so with with the dual aspect theory. True, we can look at a book under the aspect of economic position (it has a price of $15, say) or we can look at it under the aspect of subject matter (its subject is astronomy, say). But the economic object and the object of the subject matter do not interact. For they are the same thing, viewed under different and incompatible aspects. Double aspect theorists owe more to Spinoza, neutral monists to Leibniz and Hume.

To conclude, may I offer a big thank you to John Schwenkler and The Brains Blog for hosting a great discussion? I have had a lot of fun and learnt a lot. I hope that everyone has enjoyed it and benefited from it as much as I have. Cheers John!



  1. Eric Thomson

    Interesting stuff thanks a lot for taking the time to post about your book! A few questions.

    1. Is this normative or descriptive (or both)?
    Is this neutral view meant to be a normative view about how philosophers are meant to approach things? Or is this also a psychological view, that you actually think children start out with this neutral view and only later come to parse the world into psychological and physical kinds? The quote from Wright suggests you think the latter, but this seems a bit unlikely given the developmental psychology of Bloom, Jean Mandler, etc.. Children seem to divide the world more deeply.

    Regardless of that, I am fine if it turns out that children aren’t little neutral monists, but it turns out that we (adults) should be. The question is, should we? On to that…

    2. Are you turning back the methodological clock?

    Next up in my worry hierarchy is that this seems a step backwards toward foundationalism and given-ism, away from methodological naturalistic “Second Philosophy” type approaches (Maddy) which seem so much more promising. It seems to be pushing us into almost phenomenological territory, which is fine if you just want to describe experiences, but at a metaphysical level always sort of left us in the lurch (e.g., Husserl or aufbau-like positivism, lots of naval gazing but never helping us understand the structure of reality). Or do you see the approach richer than that, more three prong, with the neutral helping us knit together the physical and psychological into an integrated picture, in a way that would be impossible otherwise? I guess I don’t see how that works out, and the way you have described this neutral level seems very psychological and phenomenological (i.e., it doesn’t seem very neutral).

    3. Where is the explanatory bite here? Is it just a promissory note?

    I’m having trouble seeing how this doesn’t just left us with the exact same explanatory gap that the physicalists have, but with even more complexity because now you have a third level, this neutral stuff. You have a psychological level of description, and a physical level of description. And also a kind of not very well defined waving at this neutral level, that doesn’t seem to do any explanatory work to help us connect the two, but somehow unifies everything. But eventually it will? Isn’t this exactly where the physicalists are?

    The talk of ulcers and stomach damage is fine, and neuroscience has done a ton of great work illuminating the tight fit between representational and phenomenal contents (e.g., blindsight, phantom limbs: literally we could write a book on this). So that isn’t anything new, and I don’t see any real explanatory bridges there, certainly not anything more than the kind of “Ooh neat!” that you’d get from a neuroscience text.

    I don’t see how neutral monism offers much explanatory purchase here, any more than the physicalist who also points out such tight correspondences, and just says that someday that the gap will someday be closed by their favorite explanatory base. Indeed the physicalist has the advantage that she isn’t positing this mysterious neutral level, but more run-of-the-mill things like neuronal processes (or functional-teleological or quantum mechanical or whatever the heck the physicalists are saying these days).

    I would really be interested in a more concrete, really developed, neutral monist explanation of conscious experience. So far it reads like a promissory note whose plausibility would depend on someone buying into your arguments against physicalism. 🙂 Would it would be safe to say that a committed physicalist, who is a methodological naturalist, probably won’t be very tempted by this neutral monism route?

    • Jonathan Westphal

      Thank you for the great questions. As to the first, neutral monism in all its good forms is entirely normative. It gives us an analysis, or tells us how we should think at a deeper level about how we think about mind and matter and their interaction. I do think that perhaps “children are little neutral monists” (nice phrase!) They certainly don’t at the outset start forming the concepts of the mental and the physical, nor even of the self or whatever. But this is an empirical and psychological (!) question.

      I do wish to turn back the clock towards foundationalism and away from naturalism and related views and towards a responsible phenomenology. I am even prepared to say that there is such a thing as phenomenology, though there need not be phenomenological problems. It is a kind of navel-gazing, and I think that there is more of interest in the navel than people seem to want to allow. ‘Is your experience the same, apart from perspective, out of both eyes?’ That’s an important question, and the answer to it cannot be given only by checking abilities experimentally. Or, ‘What is the correct _description_ of the rotating snakes illusion?’

      How’s that for navel-gazing?? The first step in thinking about the snakes is surely a description what we see or “see” or *see* or . . .

      About the explanatory gap. The point of the neutral monist ontology is that it has in it the things (such as colours, sounds and so on) that cannot be extracted from the physical world, as described by physics with concepts such as _changes in electromagnetic flux_ or _compression wave_. These things have themselves to be constructed out of the neutral elements. ‘Would it would be safe to say that a committed physicalist, who is a methodological naturalist, probably won’t be very tempted by this neutral monism route?’ Well, if you are “committed”, I think you will be able to resist temptations of neutral monism. And if you are a methodological naturalist, card-carrying, that is, it is unlikely that you will find neutral monism very appealing. But you should! Why do people become naturalists and physicalists? I can’t answer that, but my sympathies are with the anti-naturalism of Wittgenstein.

      • Eric Thomson

        I am not *anti* phenomenology. I am more concerned with treating phenomenology as a kind of first philosophy. This Cartesian approach, of starting with descriptions of our mental states (or neutral states, which seem suspiciously mental), and thinking you are going to get very far with that, has a very bad track record.

        That’s what I was getting at by asking if you were going for a more three-pronged approach, where you triangulate the three domains (neutral, psych, and physical). This seems more promising, something like Flanagan’s constructive naturalism.

        But my point was that, when taken in an epistemic foundationalist direction, it doesn’t have a good track record when it comes to yielding much in terms of *metaphysics*. Indeed one of phenomenology’s strengths is that it is good at bracketing out metaphysical questions and focusing on experiences, but this is also one of its weaknesses as a generative metaphysical programme: it ends up being consistent with *every* metaphysics.

        So I am all for phenomenology, and careful description of illusions and how they appear to us.

        But the point is how do we explain such experiences? That’s what we started with. For the physicalist, it will be explained in terms of whatever biological/neuronal/physical/functional/teleological whirrings. Also, something you never really address in all the conceptual issues is basic issues like the asymmetry in that the brain seem the root here in that mental states supervene on brain states (individuated functionally or whatever I don’t care), not vice-versa.

        And I don’t see how neutral monism is not just sneaking in phenomenal at the ground floor. And if you do *that*, then of course you can dissolve the problem but you have basically become an idealist. At any rate, that’s one reason I think it would be nice to really see a worked-out detailed example to really cut my teeth on to see how all this flows and get a sense of its reasonableness.

        Finally I should admit, as a physicalist-leaning agnostic about all this, I do think that phenomenology plays a key role in the “root” intuitions here that you started all these posts. Without phenomenology we would not know that there is a problem of consciousness in the first place. That is, the explanatory gap forces itself upon beings with a phenomenology that can discuss their experiences (e.g., not cats, who I assume are conscious but not self-consciously so). And I think the “big divide” in consciousness studies may be between people who want to repudiate phenomenology altogether (and, say, only allow heterophenomenology or some such), and those who think that excluding phenomenology from the study of consciousness would be like excluding mass from the study of planetary orbits.

        • Jonathan Westphal

          I agree that very much that ‘Without phenomenology we would not know that there is a problem of consciousness in the first place. That is, the explanatory gap forces itself upon beings with a phenomenology that can discuss their experiences (e.g., not cats, who I assume are conscious but not self-consciously so).’ Colours and sounds and the other “neutral” elements, if indeed they are neutral, are not going to go away from the spade-turning bottom of epistemology, nor of metaphysics I suppose. In general, I am not a special friend of metaphysics, so when Mach declares that ‘The world is a sensation’ I do shudder, but I know what he means, and he was emerging from an idealist phase, I think. He means that what is fundamentally real are phenomenal atoms, not physical atoms, and that physical atoms are logical constructions in Russell’s sense. And there is a real point to this. Planck concedes the very point at issue, in 1909, when he says that physics has “gone beyond” colour and that colour is not part of physics. It is characteristic of sensations; and here the phenomenal properties are all set to create the mind-body problem. One could say that even if physics implies that there are atoms, the phenomenological and epistemological arguments against them are unaffected.

          Why would you suppose that neutral monism is idealist, as Mach may have done before he was able to extricate himself? Only I think if you accept that there is a distinction between the physical and the phenomenal, and then you plonk down the phenomenal onto sensations, which are non-physical – buyer beware! But this is the thing that Mach wanted to deny, to the end, even perhaps as late as 1915 if my history is right.

  2. vicp

    Gents, If we are talking children, the primary thing children recognize is their body or their own embodiment. Neutral monism may be a philosophy of embodiment and minimal language. Colours and searing are language or words or minimal language.

    Children are neutral monists because they have minimal language and in early childhood language begins to impose its major function of forming our social reality. The first word a child learns is the word for mother or the first and biggest object of their social reality.

    During the Christmas Season people are enamored because the bright lights, objects, music and behavior draw people back to their childhoods or foundational self. The Season also ends with a celebration of celestial time at midnight December 31.

    Mariah Carey’s song which she wrote is brilliant because the “You” she longs for may be our lover or could also be a lost parent, friend or even a pet. The You is actually YOURSELF or the one who made you feel complete and is now or temporarily missing. What she does is cast off all of the objects and acts of the Christmas Reality because all she wants is a basic self. Of course she shows off her beautiful sexy body along and body parts which are also significant for mothering. The background set of surreal rotating images which represent dream states.

    Merry Christmas

  3. Jonathan Westphal

    There is something very intense about early sensations, and it has a lot to do with psychological identity, I agree. Sounds and smells are very intense at the age of 3 or 4, and they form us in a special way. It takes something powerfully destructive to have effects of a similar magnitude on an older but healthy person, e.g. “shell shock”, which tuns out to have a neurological basis in a honeycomb pattern of lesions very different from those caused by car crashes and opiate overdoses condition. It has reappeared in neurological studies of soldiers suffering the affer-effects of the IED blast.

  4. vicp

    Jon, Thank you so much for the replies. I like Dr Sapolsky’s videos, including the one on the limbic system which I confess I listened to in entirety a few months back but not recently: He explains how olfactory sense is more primitive and directly connected to the limbic system vs other functions and touches a lot of philosophical insights.

    If talking children and Santa, we are definitely talking the emotional self but I was also thinking about the embodiment from a sensorimotor perspective as well.

    I have a very interesting question about sensorimotor embodiment which you may be willing to entertain?

  5. Jonathan Westphal

    Of course I would like to hear the question, but I’m not necessarily the right person to answer it, as I am not an expert in the sensorimotor system as a whole.


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