Is Gravity a Mystery?

 

Gravity was certainly viewed as a mystery upon its introduction into the learned world, on account of its action-at-a-distance powers. How can one body affect another across great distances without any connecting medium? But that is not the aspect of gravity I want to focus on; my concern is with the idea that gravity is an attractive force. It is commonly said that bodies exercise a gravitational pull on other bodies: they draw other bodies towards them by means of an emanating force. An object strays into the earth’s gravitational field and feels the gripping power of gravity pulling it downwards, and down it goes ever more rapidly. The earth actively attracts it while it is held in gravity’s grip. Gravity is thus an attractive not a repulsive force. But what is it we actually observe about such motion? We observe one object moving towards another; we observe no attractive force. This is an interpretation of what we observe. Similarly for tidal motion, the motions of the planets around the sun, and any other gravity-induced motion. Two or more objects are observed to be in relative motion and we hypothesize that there is an attractive force acting between them. But why don’t we interpret what we observe differently—why don’t we say that one object is surging towards another, actively moving in its direction under its own power? Why aren’t the waters of the world reaching out to the moon, surging in its direction? People can be irresistibly attracted to other people, powerless in their grip, but they can also just move towards them of their own volition: so why can’t we say that that’s what objects do when the force we call gravity is operating? It isn’t that the earth has pull; rather, meteors (and the like) have thrust. Isn’t this hypothesis equally compatible with the observed motions? The concept of attraction clearly derives from human psychological attraction, but inanimate bodies don’t attract in this sense; so what grounds the idea of gravitational attraction? Isn’t this gratuitous anthropomorphism with no objective basis? If we must have an invisible force, why can’t it be a propulsive force possessed by bodies in relation to each other? The sun isn’t pulling the planets in their orbits; the planets are propelling themselves around the sun—they have that active power. They propel themselves faster the closer they get to the more massive object, according to an inverse square law; but the object towards which they move exercises no pull on them—nothing like being yanked by a rope. Gravity is the power of objects to move towards other objects not the power to move other objects: the moving objects have the power, while the stationary object lacks any power to influence the movement of remote objects. Couldn’t there be a world in which this was the actual situation—no pull but all thrust? We have got into the habit of describing the motions we observe by using the concept of attraction, borrowed from human interactions, but aren’t the motions equally describable by using the concept of thrust? The sun isn’t coercing the planets to orbit it in the way they do; the planets do this of their own volition, so to speak—it is in their nature to move this way. They move according to Newton’s laws but not for Newton’s reasons: the explanation of their movements is quite different. Newton had no account of what confers the power of attraction—no physical basis for this power  [1]—but it is a question why we should talk this way to begin with, given that the observed motions are compatible with the rival hypothesis just sketched. The ability of an object to propel itself is admittedly puzzling, but on this score the two theories seem on a par. Why posit attraction?

            My point here is not that the thrust theory is true, or preferable to the pull theory; it is that we don’t knowwhich is true. Of course, it can also be said that neither theory is true: maybe there are no such forces in the universe but just the motions we observe. Such a view has been held by some physicists, and the General Theory of Relativity can be interpreted as replacing forces with the structure of space. We know that gravity exists in the sense that there are universal laws of motion of the kind adumbrated by Newton and Einstein, but we don’t know what kinds of force govern it. This is a mystery, an area of deep ignorance: we don’t know whether the earth pulls or whether objects seek it out or neither. Or both: maybe the earth pulls a bit and falling objects thrust a bit. We don’t know what forces bodies intrinsically have, only how they are disposed to move. We don’t know how forces act over empty space, but we also don’t know how the forces are distributed. I notice that some physicists eschew talk of attraction and pull, no doubt sensing their empirical vacuity; but then they are left with no causal explanation of the movement of bodies. Either movement is a mystery or gravity is a mystery or both. Not only do we not know what grounds the (alleged) gravitational pull of the earth (Newton’s lacuna); we don’t even know that it has any such pull. The whole thing starts to seem pretty damn mysterious, not to say spooky. We don’t know how gravity operates over the void; we don’t know what confers it; and we don’t know whether the force is attractive or propulsive. It is as if we observe a group of people moving around each other, some moving towards some central person, and we assume a force of attraction emanating from that central person—while it could be that they are all moving of their own accord with nothing coercive emanating from the center. The truth is that we are simply ignorant of the underlying causal structure of things.

            Now consider those billiard balls that so fascinated Hume. Here the causal nexus is one of propinquity—no action-at-a-distance (allegedly). We tend to assume that the cue ball carries the power to move the target ball: its motion is “transferred” to that ball. It has a pushing power, while the target ball just passively receives this power and is propelled in a certain direction with a determinate velocity. Hume was very concerned about this nexus, but he assumed that the cue ball has the coercive power. But is this the only possibility—what about the idea that the target ball has the power to move off when touched by the cue ball? It is the occasion of the movement but not the cause of it (Occasionalism without God): that is, the target ball propels itself away when triggered to do so by the cue ball. The case is like a person being given permission to do something and thereupon acts in a certain way: all the causal power comes from within the person not from the permission. Why isn’t this the way causality works? So-called causes don’t have causal power; so-called effects do. The triggering object has no power by itself to bring about a change in the affected object; rather, the latter object has the power to change when impinged upon by the former object. Contact causation is not a matter of a transfer of power (“energy”) from impinging object to impinged-upon object; it is a matter of the latter object having the power to move itself when certain conditions obtain involving the former object. This is an ignition-and-thrust model of causation (like rockets) not a transfer-of-power model. Active power is located in the effect object not the cause object (so-called). Again, the point is not that this model is the true theory of causation; it is that we don’t know it’s not true. We don’t know how causation works, even in this fundamental respect. Causation is thus a mystery. We talk in certain ways, probably deriving from human experience, but we have no justification for this way of talking over other ways—none that is warranted by the observable facts. Hume was right about how little observation of causal sequences tells us about the nature of causation; and it turns out that it doesn’t even tell us in which objects causal power is located. We are deeply ignorant of causation, even of the contact kind, i.e. causation is a mystery. We don’t know what is going onwith causation even in the simplest cases (which is why Occasionalism is even a theoretical possibility). The cause-effect nexus is like the mind-body nexus—an area of profound ignorance.

            Electromagnetic causation is also deeply mysterious. Here we are said to have attractive and repulsive forces (related to so-called positive and negative charge). But why employ the concepts of attraction and repulsion (pull and push)? All we observe are movements of particles towards or away from other particles; it is a further claim that attractive and repulsive forces govern these movements. Maybe particles propel themselves in the direction of other particles instead of being attracted by them (similarly for repulsion): there is no active pulling force, but rather a spontaneous tendency to move towards other particles. Or maybe there are no such forces but just brute motions, or maybe a bit of both. We don’t know. We just talk in a certain way because it makes intuitive sense to us given our psychology; there is no objective evidential basis for this mode of talk. So again, electromagnetic causation is mysterious—far from transparent. We try to summarize the motions we have observed with concepts drawn from common sense and originating in human agency, but really we are flailing in a sea of ignorance. Even so-called mechanistic causation is full of mystery, as Hume pointed out in the case of those careening billiard balls.

  [1] Note that mass could equally be the variable with respect to which a repulsive force is proportional. In a possible world in which massive objects repel other such objects, instead of attracting them, we could equally find a lawlike correlation with mass. There is no intrinsic necessary connection between mass and attraction—or none that we can discern.

 

 

Organs and Organisms

 

At first sight the distinction between organs and organisms looks clear and principled: an organism is an individual animal or plant while an organ is a functional part of an organism. An organ functions on behalf of an organism while an organism functions only on behalf of itself. But this apparent clarity begins to blur once we examine the matter more closely. Consider symbiosis: here one organism uses another as an organ, in effect. If the symbiosis is mutually beneficial, each organism uses the other as an organ, since the other functions as an aid to survival for its partner. It may even be a vital organ, if one organism can’t live without the presence of the other. If the benefit goes only one way, then one organism functions as an organ for the other but not vice versa (e.g. a spider using a plant to anchor its web). Some parasites function as organs inside the host organism, as with those bacteria that aid digestion. If we think ant colonies are organisms in their own right, then each ant is an organ within the whole colony. Why aren’t parent organisms effectively organs that help offspring organisms survive? Why aren’t the trees that birds live in organs of birds? The concept of an organ is functional and many things act functionally to aid the organisms they interact with: there are organs within animal bodies and there are organs outside of them (bird nests, beaver dams, spider webs, etc.). Come to think of it isn’t the whole environment of an organism one of its organs, at least in so far as it affects the survival prospects of the organism? Symbiosis is defined simply as (unlike) living things living together, and this is ubiquitous. Many organisms are simultaneously organs for other organisms. In addition, if we follow selfish gene theory, each organism functions as an organ for the survival of the genes: the organism is a “survival machine” enabling genes to be passed onto the next generation—not different in principle from hearts and kidneys.  [1] And isn’t what we call the self or mind really an organ of the biological body, enabling it to reproduce itself? Persons are organs with respect to reproducing bodies (not only that of course). Being an organ is defined functionally and the concept allows for a very wide extension, including whole organisms. Perhaps every organism is an organ of some other organism (e.g. fleas and lice).

            But what about the other way round—are organs also organisms? Not as the terms are customarily used: we don’t normally speak of the heart or kidneys as organisms in their own right. We know that some organs are organisms by the above reasoning, but are all?   Are there theoretical reasons that could justify extending the label “organism” to all organs? How, indeed, are organisms to be defined so as not to generate this consequence? Merriam-Webster defines “organism” as follows: “A complex structure of independent and subordinate elements whose relations and properties are largely determined by their function in the whole”. But doesn’t this apply straightforwardly to organs within the body? They too are complex structures made up of functionally interacting parts (think of the heart). We can’t add “and is not an organism” because some organs are organisms. The OEDoffers the rather unhelpful, “An individual animal, plant, or single-celled life form”: this is irredeemably disjunctive and fails completely to say what animals, plants, and single-celled life forms all have in common that makes them organisms. It is instructive that the term “organism” was only introduced in 1774 and is not part of natural language: it is clearly intended to cover and unify a wide variety of cases (“animal” is not general enough). It expresses a cobbled together concept designed to fill a taxonomic gap. It is obviously derived from “organ” and carries some of its sense: an organ is precisely an integrated discrete biological structure that behaves in a unified way. True, organs typically exist inside whole bodies, but this is not a necessary truth and is hardly part of the very definition of an organ. Organs could be organisms in some possible world (as mitochondria in cells were once independent bacteria): the organs constituting bodies could be organisms that have come together to form a more complex organism, perhaps leaving the collective when the time is ripe. Couldn’t it turn out that animal bodies on earth are all composed of organisms that have joined together: they may each have their own pocket of sentience and their own evolutionary agenda. In effect, they function as parasites or symbionts in relation to the rest of the body. But even supposing this not to be the case, there are good theoretical reasons for classifying organs as organisms, i.e. as not fundamentally distinct from what are usually called organisms. For the organism-centered view of biology is really an out-of-date anthropocentric approach to biological phenomena. Natural selection selects primarily for organ-types—that is what the survival of whole animals and plants depends on. The genes have to build good hearts and kidneys and brains, so that their own survival will be ensured: these are the true units of natural selection. These are what compete in the battle for survival. Ultimately this is because traits are the essential entities, and organs have traits.  [2] Natural selection operates over traits of organs, selecting hearts and kidneys that perform their function better than other hearts and kidneys. Organisms survive because their organs are well designed, not because they have properties that somehow go beyond the properties of their organs. We tend to focus on organisms because we are organisms ourselves, with consciousness and intelligence; but nature has no special interest in those traits of (some) organisms. In the case of insentient organisms we have a bundle of organs and the entire process depends on how well they function: they are what survive (or don’t) into the next generation—along with the genes that make them. The evolutionary process is gene-centered and trait-centered, with organs carrying the selective burden; whole organisms are just vehicles for these entities (the true replicators). The organism, as traditionally conceived, is a secondary player; the organs are the elements of the evolutionary mechanism. The species or group is made up of individual animals or plants and has no evolutionary significance apart from that (there is no species or group selection), but the whole animal or plant is made up of its organ parts and has no evolutionary significance apart from this. Thus we may as well homogenize the field and classify organs as organisms, i.e. as the functional units of natural selection. The distinction between them is artificial from the point of view of scientific theory, reflecting as it does an anthropocentric view of the biological world. What we really have are genes, biochemical molecules, cells, organs, and collections of organs (“organisms”): these are the true natural kinds of biology—the entities with objective existence and nomological relevance. Biology need not employ an ontology of organisms at all, as organisms are traditionally conceived.  [3]

            I think clarity is served by instituting another terminological revision (dated 2021): let us introduce the neologism “biocule”, based on the familiar “molecule”. Cells, organs, and organisms are all biocules—life forms of various types, biological entities. The evolutionary process operates over biocules, these being the true natural kinds of biology. We can certainly carry on speaking of cats and cabbages, hearts and kidneys, but we retire the organ-organism distinction, save as a vernacular convenience. Clarity is served by collapsing that distinction, thus rating organisms as organs and organs as organisms, so far as biological science is concerned. The official designation is “biocule” construed as a more general and abstract type of biological entity. The term “organism” has outlived its theoretical usefulness, and it was always rickety (what about viruses?). It really is, as the OED concedes, a disjunctive concept with no unitary overarching meaning. Animals and plants and single-celled life forms are really very different, and using “organism” for all of them is misleading in suggesting a common essence. Up to 1774 people got by with more restrictive nouns like “animal” and “plant”, which are perfectly kosher; the neologism “organism” came from a craving for generality (Wittgenstein’s phrase) that has no real basis in nature. Now that we are used to identifying other entities as the units of natural selection (notably genes) we can move away from the focus on individual organisms. Organs and organisms are not importantly distinct from the point of view of biological science, and hence from an accurate vision of how nature is objectively organized.  [4]

            Let me end with a fun thought experiment designed to nudge intuition in the direction I am recommending. Suppose some entrepreneurs decide to market internal organs as pets. They detach the organs and put them in tanks, still alive, still glistening. Hearts still pump, kidneys still filter, brains still think (or send nerve impulses around). Customers keep these organs in tanks like fish and give them pet names. They grow fond of them. They put decorative plants next to them. Wouldn’t they come to regard them as like whole organisms? After all, they are composed of living biological tissue and have a definite structure, just like regular pets. The organs have become organisms—units of life with their own separate existence. It’s only because we don’t normally see organs that we refuse to see them as organism-like; once we get to know them we might shift our attitudes towards them. Surely the brain is very like a typical organism in that it houses sentience—a whole species might just consist of brains floating in vats!  [5] The deep similarities between organs and the bodies in which they are located are sufficient to warrant a classificatory scheme in which no deep distinction between them is recognized. We just have biocules at different scales: from cells (and their constituents) to organs (and their parts) to organ systems to totalities of organ systems (organisms). The organ-organism distinction is really an untenable dualism. We may keep it for pragmatic reasons, but it is no part of a properly scientific conception of biological reality.  [6]

 

  [1] The phrase “survival machine” is from Richard Dawkins, The Selfish Gene (1976). I am presupposing a good deal of his appetite for terminological innovation in the light of new theory.

  [2] I have discussed this elsewhere: see “Trait Selection” in Philosophical Provocations (2017).

  [3] Does biology need to worry about whether caterpillars and butterflies are identical organisms? Does it matter to biology whether organisms exist over time? Does biology need to distinguish organisms from ensembles of traits?  

  [4] I haven’t discussed whether genes are also organisms. The question brings up the issue of whether genes are living things. I am inclined to say yes, because of their role in the generation of life and their propensity to replicate. They function symbiotically in relation to the body, coexisting with it to their mutual benefit. Are they also organs? Some might say they are organs of the organism, enabling it to reproduce itself in offspring; but this is really the wrong way round—it is more that animal bodies are organs of the genes, enabling them to reproduce themselves. Questions of taxonomy are theory-dependent, so taxonomic labels may have to be altered when theory changes. We are now at the point at which genes, organs, animals, and plants are all rightly grouped together as biocules, with the notion of organism used promiscuously or not at all.

  [5] Is the mind an organism? The brain is, given that bodily organs are. The idea is not outrageous, ordinary speech notwithstanding: it is a biological organ like other biological organs and has many biological properties (hereditary, functional, vulnerable to sickness and accident). It’s an organic unity, a biocule, a chunk of biological real estate (among other things).

  [6] We make a distinction between tables and chairs but that distinction is no part of physics: its natural kinds don’t coincide with the kinds distinguished in ordinary discourse. Similarly for “organ” and “organism”.

 

Lady Chatterley’s Nature

 

D.H. Lawrence’s Lady Chatterley’s Lover is clearly obsessed with nature. Nature is lovingly described; most of the action takes place in a wood; animals (pheasants, a dog) are among the dramatis personae. The text is replete with naturalistic description. Nature is set over against industrial civilization in the form of collieries, as well as intellectual civilization in the form of works of fiction and pictorial art. Mellors represents nature; Sir Clifford represents predatory capitalism and intellectual refinement. Mellors is a gamekeeper who lives in a wood in a small cottage and hut; Sir Clifford lives in a grand country house with servants. Mellors roams freely through wood and world, while Sir Clifford is confined to a wheelchair (the result of an industrialized war). There is a tremendous amount of discussion of the evils of civilization and the healthy cleansing power of the natural world. The author is clearly on the side of nature.

            This is the context in which to view the most salient and notorious aspect of the novel: its sexual explicitness. Why did Lawrence insist on this? It didn’t even exist in the first version he wrote, and it would obviously prevent the book from being published, as well as generating enormous critical disapproval: so why did he choose to go there? Two suggestions may be made. One is that he relished the technical challenge of writing explicitly about sex—how is the writer to do it, in what vocabulary, in how much detail, to what effect? The other is that he believed not writing about sex explicitly in a novel about adultery was simply cowardly, caving in to an irrational taboo (cf. Joyce’s Ulysses). No doubt both these motives were operative and both are fully justified, but I think the reason goes deeper and is more thematic. It is that Lawrence wanted to treat human sexuality as a fact of nature, as a natural biological phenomenon. He wanted to depict it as he might depict the behavior of the pheasants or the dog Flossie—as we might say, scientifically. He was a great describer of nature, and this was an area of the natural world that had yet to be described. In other words, he wanted to stress the continuity between nature as a whole and the part of it constituted by human sexual behavior (including sexual anatomy). So we are treated to a naturalist’s description of lovemaking between Mellors and Lady Chatterley, right down to penis and vagina. The words “fuck” and “cunt” are not shied away from. Thus sex belongs to nature, which is a Good Thing in Lawrence’s worldview. And it has to be said that he does it remarkably well: that is the marvel of the book—how well he brings off this literary feat. Has sex ever been written about so evocatively, and straight out of the gate too? We come to see sex as part of the natural history of humankind alongside eating and drinking. The body emerges as a site of pre-civilizational innocence and splendor—nothing to be ashamed of, nothing to hide or euphemize. The body, for Lawrence, is deep. It knows things. In order to convey this message the author needed to engage in some serious corporeal description. He didn’t want to shock; he wanted to recognize, to reflect. He wanted sexual realism. That is the underlying reason for writing about sex in the way he did—to make the novel realistic, not idealized or cowardly or simply false to the facts. There is nothing titillating or pornographic in the way he depicts sex (it is tame by modern standards, though still powerful); he simply gives you the nuts and bolts, the way things actually are (or were at that time).

            Take his use of the word “crisis” to describe orgasm (he also uses that word). Yes, he is going to talk about male and female sexual climax (“coming off”, as the book quaintly says), but the word “crisis” injects a curious ambivalence into the description, producing a kind of literary double take: how is something so good like something generally disagreeable? It also enables the writer to avoid dull and repetitious sexual language that might evoke the wrong kind of response (Lawrence is actually a very moralistic writer). How is it possible to derive the dubious joys of pornography from this odd word? Or consider the famous passage about entwining flowers in Connie’s “maidenhair”: here we see a literal joining of nature and the sexual organs, as if hair and flowers are of the same stuff. Lawrence’s underlying theme is sounded loud and clear: sex and nature are one. And if one is beautiful, so is the other. This is not about playing naughty games with the gamekeeper in classic British “Carry On” style—there is nothing remotely funny about it–but rather an attempt to free sex from its conventional associations and return it to our organic nature. The flowers, the pheasants, the wood, and the lovers—all belong together in the natural scheme of things. And all contrast with the horrors of industrialized working-class life and the dry stiffness of the British aristocracy. It is to be noted that God is never mentioned in the book, and surely that is not an accident: nature worship takes God’s place. The problem Lawrence is unable to solve, though the book shows he was well aware of it, is how to integrate the advantages of industrialized society with the primordial attractions of nature. Money may be bad, as the book continually insists, but do we really want to go back to a world in which money does not exist? And how are comfortable houses to be built and health improved and starvation avoided? It might be nice to run naked in the rain once in a while, as the lovers do, but do you really want to be drenched all winter long?  Still, in that primitive little hut in the woods Mellors and Lady Chatterley can revel in the dream of pristine nature: they can call on their sexual nature to join them with the rest of nature, albeit briefly.

 

 

 

Truly Physical

 

If we consult the OED on the word “physical” we find the following as the primary definition: “relating to the body as opposed to the mind—involving bodily contact or activity”. Only the third definition given captures the sense intended by philosophers: “relating to physics or the operation of natural forces generally”. The primary definition might be paraphrased as of the body: to be physical is to involve the human body, to be located in the body, to concern the body—as opposed to the mind, the psyche, the spirit, the soul. This is the sense employed in such locutions as: physical education, physical exercise, physical therapy, physical anthropology, physical abuse, physical appetites, physical examination, physical love affair, and physical beauty. The word “physical” in this use is close to “fleshly”, “somatic”, and “carnal”: to be physical is to consist of (or somehow involve) flesh and bone, blood and guts, muscle and mucous. The organs of the body are physical in just this sense, being precisely organs of the body. The brain is no exception: it is indisputably of the body, one of its parts. The mind, by contrast, is not clearly of the body, which is why it has been deemed immortal, separate from the body, a different kind of thing entirely (not even material). Mark that to be physical in this sense is not to be physical in the sense favored by philosophers: something can be of the body without being fully describable by physics. A vitalist could believe that the organs of the body are not reducible to physics, holding that a special force animates living tissue; or you might think that biological concepts are not reducible to the concepts of physics and chemistry.  [1] We can be quite neutral on the science and metaphysics of the living body while declaring certain things to be of the body—or not of the body, as the case may be. In the past the mind was thought to be not of the body and hence not physical in the present sense: it was deemed immaterial, incorruptible, located elsewhere, not beholden to the body for its existence, and maybe not even causally connected to the body. Thought, in particular, was taken to be non-physical in this sense—not an attribute of the body at all. Thinking is not a bodily process like digestion or breathing  [2]: the soul thinks and it is not of the body. Thus we can coherently envisage a doctrine, viewed as radical, that maintains that, contrary to tradition and maybe even common sense, the mind is physical in the sense we are considering: it is of the body. We can call this doctrine “physicalism”, carefully distinguishing it from the doctrine usually so called by philosophers, i.e. the doctrine that the mind is reducible to the entities and properties described by physics. The former doctrine is not hostage to the fortunes of the latter doctrine; indeed, proponents of it might be hostile to that doctrine, viewing it as false, vacuous, or even nonsensical. Being of the body is not to be equated with being as physics describes things, now or in the future: for it may be held, for various reasons, that there is no merit in the idea that the body is purely physical in that sense. In any case, I wish to investigate the former doctrine in its own right: the idea that the mind is really a bodily thing and not a non-bodily thing—which I will call simply “physicalism”. It might also be called “bodyism” or “somaticism”, but the dictionary licenses using the word “physical” to refer to the doctrine in question. Is physicalism in this sense true?

            It is important to see what physicalism, as so defined, opposes. Take mental illness: a non-physicalist would hold that mental illness is caused by evil spirits or impure thoughts or developmental factors operating independently of the body (including the brain). It should therefore be treated by a priest or a psychoanalyst not by a neurologist. But a physicalist about mental illness would hold that it has causes within the body of a chemical nature and that the appropriate treatment should be directed at the body (drugs, surgery, physical exercise, etc.). Even if the etiology is psychogenic, the illness itself is connected to the brain in discoverable ways and could not exist without the brain’s cooperation (so to speak). Mental illness is not a condition of an immaterial substance cut off from the body but is deeply enmeshed in the body’s biological activity. Thus we have a physical (bodily) account of mental illness as opposed to a supernatural (non-bodily) account. Note that we are not saying that the psychological manifestations of mental illness are reducible to brain states or facts described by physics; it is just that mental illness is body-involving, body-located, inextricably bound up with the body. Let’s even boldly state that we have discovered this to be true by empirical investigation, whatever may be the case with respect to the reducibility of psychology to physics. In the same way it may be said that mood swings and depression are physical phenomena, being occasioned by chemical imbalances and the like; they are not perturbations of an immaterial spirit lurking somewhere in the general vicinity the body. Ditto for hunger and thirst. Emotions in general might be similarly viewed: they involve the body in various ways—flight, approach behavior, butterflies in the stomach, genital arousal, and so forth. Specific parts of the brain are activated during emotional excitation. Emotions are bodily phenomena not disembodied states of a quasi-divine soul: they have a “physiological basis and origin”, as one dictionary says under “physical”. As for perceptual experiences, the physicalist will assert that they are intimately joined to the bodily sense organs and hence “of the body”: seeing is a physical process because of the bodily eye, as are tasting and smelling because of the mouth and nose. We don’t see, taste, and smell in some way removed from our bodily nature: these are physical processes (even if the sensations involved are not reducible to brain states). They are anchored in the body, dependent on it, shaped by it. Hence physicalism in the present sense is true of emotions.

            The case of thought presents more of a challenge to this brand of physicalism, because its bodily connections are not so evident. Here the case for a non-bodily immaterial substance has been at its strongest. This tells us that physicalism of the kind under consideration is not a trivial or empty doctrine—it has polemical bite. It might even be false!  [3] But the determined physicalist is not without resources even in the case of thought: putting aside the existence of regular brain correlates, the physicalist might insist that thought has bodily functions in the shape of behavior, and that it plausibly has an evolutionary explanation that invokes aspects of the organism’s body.  [4] It is the function of thought to control the body’s activity so as to secure the organism’s goals, and thought (it may be suggested) arises from features of the body involved in activity involving the hand and mouth. Evolutionary change builds on prior traits of the organism and thought must have developed from earlier properties of the body—or so it may be contended. So thought is not as disconnected from the body as may appear at first sight: there is thus room for a physicalist account of its origin and function. Thought is physical in the sense that it is of the body and not removed from the body, as religious dogma and dualist metaphysics may require. Logical reasoning, like mental derangement, has its somatic roots, its bodily bedrock, its flesh and blood associations. This is not to say that logical reasoning is reducible to the motions of matter, as the usual kind of physicalism claims; it is just to say that it is connected to the body in significant ways. The mind is thus “of the body” not something existing in splendid isolation from the body, as in traditional forms of supernatural dualism. Its ability to exist in disembodied form is accordingly put into question, making physicalism at odds with religious conceptions. I venture to suggest that we have discovered this to be true by a mixture of empirical investigation and philosophical reflection; and it in no way depends on accepting physicalism in the usual sense intended by philosophers of mind. The two doctrines say completely different things. I would say, then, that the former kind of physicalism is true, uncontroversially so in today’s intellectual climate, while the latter kind of physicalism is not true (or even really intelligible). It is a question whether the attraction of the latter doctrine, such as it is, owes anything to the evident appeal of the former doctrine: some sort of physicalism is true, after all, though not the sort commonly advocated today. Do we hear echoes of the one in the other and mistakenly conclude that it must be true because the other is? And let us note that the dubious doctrine itself makes no explicit reference to the body: it simply announces that mental phenomena can be explained in terms of the concepts developed in physics to deal with the inanimate world—the living body as such is left out of account. Clearly this is an extremely ambitious doctrine going far beyond the relatively anodyne suggestion that the mind is inextricably bound up with the body. Neither form of physicalism entails the other, but both can be expressed using the ambiguous term “physical”–one sense yielding something true, the other sense not so much.

            A glance at the history may be helpful. Nineteenth-century science, particularly biological science, made great strides in understanding the body, including the brain. The mind came to be seen as an outgrowth of the body, fostering the doctrine that the mind is really a function of the body.  [5] This superseded older dogmas founded in religion that sought to place the mind in a separate non-bodily realm. The doctrine I am calling “physicalism” was thus firmly established at this time and only confirmed by subsequent study. This intellectual stream is separate from the metaphysical materialism that goes back to Hobbes: that doctrine was never firmly established and, according to some, never will be (for many reasons). I am simply pointing out that the two doctrines labeled  “physicalism” are quite different, so that the fate of one does not depend on the fate of the other. We can therefore be “physicalists” without being physicalists—the mind is “of the body” while not being “material” (whatever that means). This seems like a good thing because the thought that the mind is in some sense “physical” is surely correct: yes, it is physical in that it is an attribute of the body, bound up with the body, situated within the body. It is not something existing separately, proceeding by its own power, capable of life without a body. Does this solve the mind-body problem? Not in the slightest: in fact it is what is needed in order to formulate that problem. For the problem is how the mind can relate to the body in which it is so clearly enmeshed—there would be no such problem if the mind were simply ontologically remote from the body. There could be a mind problem if the mind had a separate existence, but there is only a mind-body problem because the mind and the body are somehow stuck together. The brain is of the body by virtue of being literally inside the body and made of the same kind of stuff as it, but the mind is not of the body in that way—so in what way is it of the body? All I am saying here is that there is a form of physicalism, properly so called, that is not the same as the doctrine usually bearing that name. The mind truly is physical, though it is not true that it is part of the subject matter of physics. The mind is physical by being biological (somatic, organic) but not by being covered by the science of physics. The old opposition between being of the body and being of the mind has collapsed, with the mind now also regarded as being of the body. In the beginning was the body (not just the body’s deeds); the mind came along later firmly attached to the body. Thus the mind is as physical as the heart or kidneys in that sense (though not in the other sense).  [6]    

  [1] We could be mysterians about the body and yet hold that the mind is physical: the mind is of the body and yet the body is a mystery. I suppose we could even be immaterialists about the body and still believe the mind is physical (bodily)!

  [2] I read somewhere that breathing itself was not always regarded as bodily but viewed rather as an influx of spirits that kept the body alive by supernatural means (or did I dream this?). When the lungs were discovered breathing came to be seen as a bodily function sans spirits.

  [3] From a first-person introspective point of view, the essential involvement of the body in all one’s mental life is by no means apparent, so physicalism in the present sense has some work to do to overcome the deliverances of introspection. It is essentially a theoretical position not one founded in phenomenology; hence it has been a matter of controversy.

  [4] I describe a view like this in Prehension (2017), especially chapter 10.

  [5] I can’t resist mentioning Freud at this point: he is a true physicalist in the present sense because he maps psychological formations onto bodily formations in his theory of the development of the psyche. Thus the oral, anal, and genital stages correspond to psychological maturation: if you want to understand human pleasure, you need to see it as emerging from these parts of the body, according to Dr. Freud. Psychoanalysis proceeds by somatic analysis. Of course, psycho-sexuality cannot be disconnected from bodily organs; it was this connection between sexual appetite and the body that led theologians to seek ways of turning the mind to higher things (up there in the soul not down here in the loins). Sexual desire is unavoidably physical (bodily) desire.     

  [6] I don’t think the view I have described here has an accepted label, or is even recognized as a theoretical option, though it evidently exists in the historical record. I have thought it worthwhile to delineate it and distinguish it from other doctrines that are more familiar. And it is nice to be able to report that at least one version of physicalism is actually true!