In his impressive book, Material Beings, Peter van Inwagen argues in favor of an organicist theory of composition, in which the only things that count as composites are living organisms. This is to say, then, that mugs, tables, automobiles, stones, and other (non-living) things we usually take to be objects don’t actually exist; instead, the only things that exist are simples (i.e., non-composite, and thus part-less, indivisible particles) and organisms. In this paper, I intend to challenge this line of thinking, and will argue instead in favor of compositional nihilism (a.k.a., ‘mereological nihilism’), a view in which the only things that have objective existence, strictly speaking, are simples. On this view, organisms exist no more than do artifacts, heavenly bodies, or anything else that is not a simple.
I will focus especially on van Inwagen’s foundational claim that at least one composite exists: the self-reflective, thinking human being. This claim arises out of the inconceivability of thinking being a cooperative activity among a non-composite collection of particles — particularly if those particles have a unified experience such that leads to the thought, “I exist.” Before addressing van Inwagen’s position, I will first explain what I mean by ‘compositional nihilism.’
In ordinary circumstances, we think of our solar system as a thing in its own right. Considered more closely, however, it seems that a solar system is not a single thing, but instead a collection of parts whose relations to one another are held together by forces for some duration of time. In my view, there is no significant difference in this respect between a solar system and any other kind of object that we take to be made up of constituent parts. A ceramic mug, for example, is a collection of various molecules (and atoms, etc.) whose relations are held in a certain arrangement by forces for some duration of time.
We experience different kinds of relations in different ways, such that we call certain kinds of particle systems ‘mug,’ and other kinds ‘solar system,’ but this is strictly due to how we happen to perceive and conceive of the world. True, we experience things like mugs and tables as being much more solid objects than a solar system or, say perhaps, an assembled puzzle (much less an unassembled puzzle whose pieces are scattered about on the floor). But this is just a matter of perspective. Upon closer inspection, it turns out that there’s a lot of space inside the ‘solid’ parts of that mug – we’re just too big to see it with the naked human eye.
Similarly, it’s also true that collections of particles can be related in ways that make that collection more or less stable or dense than other collections of particles. Indeed, this is part of what gives us the commonsense impression that things exist as individuated objects. Stability and density make it possible to set a mug on top of a table without the mug merging into the table, and to fill that mug with hot water without the water becoming ‘part’ of the mug. Other sorts of relations, such as those we experience as ‘hot’ or ‘cold,’ make it that if you put a piece of ice into that hot water, the piece of ice will dissolve (from a singular object into a diffuse collection of water molecules), and the water will become cooler.
Our rich and consistent experience of these sorts of activities among particles mislead us into believing that mugs and solar systems are things that exist in their own right. Indeed, it is only in our experience and concepts that these collections of particles take on anything like an existence as singular entities. The more solid a collection seems, the more we take for granted that collection’s status as a composite. But again, it is due to the nature of our experience — i.e., shaped by our perceptual equipment, mental processes, and so on — that some collections of particles appear to us as solid objects such as mugs, or less solid objects such as clouds or disassembled puzzles, while other (indeed most) collections of particles don’t result in any sort of notice at all (e.g., the collection including George Clooney’s right pinky finger and the vibrating air molecules currently emitting from your blinking eyelids).
To be clear, when I refer to a ‘composite,’ I mean what philosopher’s usually mean by this term. That is, a singular thing that is composed of smaller parts. Those parts themselves may also be composed of smaller parts, but I’m not going to be picky here about these sorts of distinctions. What I’m essentially concerned with is the idea of two or more parts coming together, by whatever means, to compose some singular thing that now exists in its own right. I reject the idea that such composition occurs, though I do accept the existence of indivisible simples, whether they turn out to be subatomic particles, waves/strings/fields of some sort, or something we’ve yet to contemplate.
There are many thinkers who maintain the existence of composites. And not just in the case of mugs, puzzles, and solar systems. For some thinkers, such as David Lewis, any two or more parts compose a singular object, even if those parts don’t exist at the same time. So, the collection of particles that include the matcha I’m currently drinking and the top half of Socrates’ head compose an individual, observer-independent object that exists as much as any mug or living organism. Whenever or wherever there are two or more particles, those particles compose a singular object. This extreme view of composition is known as ‘unrestricted mereology’ or ‘universalism,’ and in part has come about as a remedy to the vagueness of relying on our perceptually informed intuitions in determining exactly which particles in the universe do or don’t compose an object. I agree with them that all particles in existence have some sort of relation, but disagree that any sorts of relations result in composite objects.
But I’m not here to argue with the universalists, so will now turn my focus to van Inwagen’s organicism, a compelling mereological theory in which the only composite objects are living organisms: human beings and bacteria exist, but tables, stars, and other non-organisms “are just not there at all.”[1. Peter van Inwagen, Material Beings (Cornell University Press, 1990), p 100.] Van Inwagen vividly illustrates this view by way of a story about a “bliger.”[2. Van Inwagen, 104.] A bliger looks like a black tiger, and is occasionally seen from a distance by the inhabitants of a rural farming community. They don’t have much interaction with the animal, and give it little thought. One day, a visiting zoologist figures out that a bliger is actually an assemblage of six animals that, for a period of up to several hours, join together to look and move like a distinct animal in its own right (i.e., in bliger fashion), and then disassemble back into six distinct animals. As such, when we consider the region of space occupied by the six animals when arranged bliger-wise, “there is no one thing that just exactly fills this region of space.”[3. Van Inwagen, 104.]
The idea here is, of course, that the bliger, strictly speaking, never actually existed. It was an illusion. We can go on calling such an assemblage a ‘bliger,’ just as we can call other kinds of assemblages ‘chairs’ and ‘puzzles,’ but, strictly speaking, these are singular things only in name.
Getting this point across relies at least somewhat on intuition: “ah, yes, I see what you mean; it seems there isn’t really something called a bliger.” To this end, I think this thought experiment does a wonderful job, and it certainly aligns with my own views, save for in one respect: van Inwagen holds that the animals that assemble the bliger are themselves composites, while I see them as not existing any more (or less) than the bliger does. His position is founded not only on intuition (more on that in a moment), but also after careful consideration of what it means to be a living organism, particularly one that thinks. Let’s first consider the former.
The notion of ‘life’ that van Inwagen is concerned with here is bound up with the notion of ‘organism.’ That is, by ‘life,’ he doesn’t refer merely being alive, like a skin cell. Rather, the word is meant “to denote the individual life of a concrete biological organism.”[4. Van Inwagen, 83.] A living organism is what happens when a collection of particles come together in such a way that results in an individuated, self-maintaining event that’s entirely biological. This self-regulating event “takes the energy it finds and turns it to its own purposes,”[5. Van Inwagen Van Inwagen, 89.] and monitors its own composition, replacing parts whenever necessary and possible. Essentially, van Inwagen is drawing his definitions from current biological science, and describing the usual processes of cellular regeneration, conversion of energy, and homeostasis, which is the means by which various systems within an organism maintain internal equilibrium. For instance, when our bodies need energy, we get hungry.
In fact, rather than referring to organisms as homeostatic, he refers to them as “homeodynamic events.”[6. Van Inwagen, 87.] This involves theories of self-regulation that allow for greater diversity and complexity within organisms, so that multiple smaller systems work together to maintain equilibrium within the organism as a whole.[7. See the National Center for Biotechnology Information for more on this: www.ncbi.nlm.nih.gov/pubmed/12805697] The long and short of all this is that van Inwagen doesn’t mean anything out of the ordinary when he talks about living organisms. I begin to grow skeptical, however, when he proposes the following formulation: “(∃y the x’s compose y) if and only if the activity of the x’s constitutes a life.”[8. Van Inwagen, 115.]
What this means is that there exists some singular thing that is composed of smaller parts, if and only if that thing is a living organism. By “activity,” van Iwagen refers to the sort of relation required between particles for their arrangement to count as the life of an organism: “multigrade causal relations must hold among the x’s if they are to compose something.”[9. Van Inwagen, 81.] It’s not clear to me, however, why these relations should compose something any more than do the relations between the particles within stones, clouds, solar systems, ant colonies, or basketball teams.
A more general concern I have is that, while I think it’s perfectly reasonable – and indeed necessary – to have an operational definition of ‘life,’ it is not clear that such definitions refer to anything independent of human needs and concerns. As needs and concerns change, so do the definitions. Given this, it’s not clear when, exactly, the activity of a system ceases counts as a life. For example, a person may be declared dead following cardiac arrest, even though the vast majority of his cells continue to live. And as medical technology improves, people can last longer and longer without vital functions before being resuscitated, so that ‘death’ today becomes ‘life’ tomorrow.[10. There are many examples to choose from; here’s one: http://online.wsj.com/news/articles/SB10001424052748704281504576327592395352666] One man reportedly lived for two weeks with no heartbeat or pulse at all, thanks to a fabricated ‘continuous flow device.’[11. http://www.dailymail.co.uk/news/article-2096314/Meet-HEARTLESS-man-able-live-heartbeat-PULSE.html] Perhaps van Inwagen can accommodate this and similar examples when he cites Jonathan Miller’s assertion that “the heart, lungs and blood, far from being responsible for life, were kept alive by biochemical processes which they shared with all the other structures of the living body.”[12. Van Inwagen, 93.] However, I think these cases are worth pointing to because they demonstrate the difficulty in pinning down what sort of activity counts as a life, a difficulty which van Inwagen would surely grant.
Many questions arise from this difficulty. Are we prepared to say that a person, most of whose cells are still alive, ceases to be a composite while declared dead (in accordance with well established standards), then becomes a composite once again when resuscitated? And if all the parts of the system are replaced through intervention as in the above artificial heart example – note that van Inwagen doesn’t consider intervention such as organ transplantation to count as instances of self-monitoring[13. Van Inwagen, 98.] – at what point does the system cease to be an organism and/or composite? (I’ll return to this question below, when I consider consciousness.)
Also, I would imagine that van Inwagen would agree that composite-hood ceases not long after the cessation of vital functions, or at least well before the body is a completely lifeless corpse, even though something like self-monitoring is still happening. Which brings into question how it is that an active and self-monitoring human body of one sort would count as a composite, but that of another sort wouldn’t. In the end, ‘life’ seems to me to be a word we use to describe a certain kind of relational status between parts — a relation that does not require composition, but that we perceive as particularly meaningful given our stake in the concept.
Despite these worries, I’ll concede for the sake of argument that there is indeed some definitive, observer-independent line between the sort of activity that constitutes a life, and the sort that doesn’t, and that we don’t need to locate that line in order to talk about the compositional status of living organisms. I am clearly alive, and Elvis Presley is clearly not. Let’s suppose that it’s the clearly living organism that poses the biggest challenge to the nihilist. Which brings us to the stage of van Inwagen’s argument with which I’m most concerned: Unity and Thinking (i.e., chapter twelve of his book).
Van Inwagen points out that the above-noted existential formulation – i.e., “(∃y the x’s compose y) if and only if…” — doesn’t do enough work on its own for his claim that living organisms count as composites. His support for that claim is the following: “(1) I exist, and (2) if I exist, I have parts.”[14. Van Inwagen, 115.] The conclusion drawn here is that (3) there must be at least one composite object (i.e., the person who self-consciously thinks, “I exist”). If this is sound, we have good reason to believe that other living human beings and, ultimately, all other living organisms — fireflies, slugs, rose plants, and so on — must likewise be composites. He goes on to ground premise (1) on the usual arguments of Descartes: for someone to wonder if she exists, there must be someone who exists to do the wondering. Van Inwagen continues along these cogito (“I think”)lines, eventually noting, “I do not see how we can regard thinking as a mere cooperative activity.”[15. Van Inwagen, 118.]
In their excellent article, “Composition as a Fiction,” Rosen and Dorr briefly address van Inwagen’s cogito argument, pointing out that the nihilist can just as compellingly argue that “certain atoms jointly think those thoughts, dream those dreams, and so forth,” and “things seem the way they do to those atoms jointly, but not to any single thing.”[16. Gideon Rosen & Cian Dorr, “Composition as a Fiction,” (Draft: September 2000), p 13.] They go on to observe that it’s not clear how the nihlist’s claims could be argued against, and that, until they can be, “compositional nihilism remains an option.”[17. Rosen & Dorr, 14.] That Rosen and Dorr are pointing to nihilism as an option, rather than as the clear alternative, is in line with the thrust of their article in general, which concludes in favor of compositional agnosticism.
This implies, of course, that they also don’t currently see the possibility of a convincing argument against the idea that things can’t think jointly. Still, this is precisely what I’d like to do here, or is at least the sort of argument for which I’d like to lay down some thought-provoking groundwork. To do so, I’ll consider whether certain case examples, beginning with that of the split-brain patient, cast doubt on the notion that thinking cannot be done in cooperation among parts. As I go along, I will also attempt to show that van Inwagen ultimately begs the question, an accusation that he himself anticipates.[18. Van Inwagen, 117] Before getting started, I’d like to make as explicit as possible what I take to be van Inwagen’s position, and how mine differs from his.
Note that I’m not attempting to formalize a premises-conclusion argument here, but rather to fairly spell out his view within as clear and coherent a framework as possible:
○ If a material object exists, it is either a composite or a simple.
○ I exist, because I self-consciously think that I exist (a.k.a., ‘the cogito’).
○ If I exist, and am material, I am either a simple or a composite. I have proper parts, all of which are material, so I must be a composite.
○ To reject that I am either a simple or a composite would be to reject materialism. That is, it would imply that my body exists as a collection of non-composite particles, while “I” exist as something other than material. It is my view, however, that, “whatever things compose me, they are all of them material — at least no further from being material than quarks and electrons are.”[19. Van Inwagen, 117] So, if I exist, I must be either a simple or a composite.
○ However, existing clearly doesn’t require thinking, as it would be nonsensical to suppose that I briefly cease to exist when momentarily unconscious. Clearly, though, once I cease to be a living organism, I will cease to exist.
○ It seems, then, that it is the status of being a living organism, rather than a thinking being, that accounts for my existence, and so all living organisms, thinking or not, must exist, and, as they have proper parts, must be composites.
Now for a brief account of my own line of thinking. In my view, we are misled by experience to believe in the existence of tables, clouds, and bligers. Instead, then, these things exist only in our experience (in a manner of speaking), and thus only as ideas. The same is true of living organisms. Van Inwagen addresses this notion, pointing out that he doesn’t understand what it means to say that he’s composed of ideas.[20. Van Inwagen, 117] So, he takes the materialist route described above. I am also a materialist, yet still maintain that it’s possible for me to exist as a thinking being with first-person experience, while being exactly equal to a living organism that is not a composite. The sense that I have of being a unified, individual entity (i.e., a ‘self’) is illusory. This becomes especially clear when considering my diachronic sense of self, in which I think that I’m the same self as I was twenty years ago, or even twenty seconds ago (indeed, it seems that all sense of self is diachronic, from which we infer a synchronic self that is never directly perceivable).
To deny this illusion appears to result in the opposite of what van Inwagen intends: dualism. For, if the sense that I’m a single, unified self over time — or even in a given moment — is not illusory, then there must be something above and beyond my material body to account for it. I don’t have space here to go further into this, nor what it means to ‘exist’ only in experience (i.e., mind-dependently or phenomenologically), so I will instead attempt the more modest project of casting doubt on the notion that thinking is something that cannot be done in cooperation between non-composite parts. In doing so, I will take for granted, as does van Inwagen, the position that whatever accounts for my existence and any thoughts I may have about my existence, is material.
To be clear, when I refer to “experience,” “first-person experience,” and “consciousness,” I mean loosely the same thing that van Inwagen means when he uses the word “thinking,” which, for him is broad, and includes things like feeling pain.[21. Van Inwagen, 118.] I won’t be picky about distinguishing these terms.
Also, it should be emphasized that, on van Inwagen’s view, thinking is not required in order for something to be a composite, nor does it explain why or how we are composites. Rather, it is evidence — conclusive evidence in fact — that “there is at least one composite material object.”[22. Van Inwagen, 120.] Van Inwagen doesn’t give an explicit argument for getting from the cogito to composite-hood (e.g., why it is that thinking can’t be understood as a “disguised cooperative activity,” while the shining of a star can be), but rather has “done no more than give examples”[23. Van Inwagen,122.] that stoke and guide our intuitions. Similarly, I cannot give a knock-down argument that we are not composites, but I can spell out some of the ideas that lead me to believe that we aren’t. Here goes, beginning with the so-called ‘split-brain’ case.
The split-brain patient’s corpus callosum — a bundle of nerve fibers that connects the left and right hemispheres — is severed as a means of dealing with debilitating seizures. Once split, the two hemispheres are no longer able to communicate within the cranium. Because of this, functions that are specific to either hemisphere become isolated, leading to fascinating results. For example, if a typical split-brain patient is shown an image of a spoon, and that image only makes it to the right hemisphere, and the patient is then asked to say what he saw, he cannot say, because language is left-hemisphere localized. However, when asked to pick out what he saw from a collection of objects, using only his left hand (which is connected to the right hemisphere) and with his vision now blocked, he will pick out a spoon. He still won’t be able to say that he’s holding a spoon, however, as only his right hemisphere has been exposed to the spoon. One gets the impression, then, that the right hemisphere is conscious of the spoon while the left hemisphere isn’t, which manifests in the behavior of the patient in meaningful, experientially robust ways. Indeed, he will even be able to draw the spoon with the left hand, yet not say what he’s drawing, so long as his left hemisphere is blocked from perceiving what his left hand is doing.[24. http://faculty.washington.edu/chudler/split.html]
Note that the above examples take place in the very controlled environment of a laboratory, where it is possible to selectively conceal information from either of the hemispheres. Split-brain patients function quite normally as they go through life, because the two sides of the brain are able to communicate with one another through cues that are external to the human body. The job of the formerly intact corpus callosum still gets done for all or most practical purposes. Whether in the lab or out in the world, however, the split-brain person still considers himself or herself to have a unified experience, and to have (or be) a unified self.
This example suggests that our experience may not be as unified as we think it is. I wouldn’t go so far as to speculate that the right hemisphere has its very own first-person experience, but it does seem that experience is fragmented, and that it’s the job of the corpus callosum, along with other parts of the nervous system, to cooperate in the smooth integration of those fragments. To be clear, this doesn’t challenge van Inwagen’s claim that only composites can have experience. The point here is simply to challenge the intuition that only an individual composite can think, by pointing to the possibility that independent areas of the brain engage in independent functions, each playing a role as they coordinate our experiences of the world and self. It’s possible that van Inwagen is, as indeed most of us are, misled by this sense of self to believe that we exist as a singular being — as a material composite.
Surely this integrated sense of self makes sense for evolutionary reasons. Consider, for instance, how difficult it would be to navigate the world if we felt sensations in real time, and there weren’t a delay that occurs when one touches hand to ankle (it takes longer for nerve impulses to travel to the brain from the ankle, so the experience of the hand is delayed for the sake of sensory integration). Our parts, it seems, work together to manufacture this and other evolutionarily beneficial illusions. That nature selects the coordinated over the disarranged doesn’t prove we’re not composites, of course. Indeed, perhaps what I’m describing is the very process out of which composites arise: Nature selects for coordination among systems, a process that one day yields a system whose biological integration satisfies the conditions for composite-hood. One step below that, and you might find life, but not the life of an organism. Still, I think it’s worth bringing up, because the aspect of that coordination that is most meaningful to humans — i.e., that which accounts for the cogito; makes possible our engagement with the world with a continuity of experience; and grounds the commonsense feeling that I am a unified self — is illusory.
One might counter that there is, nevertheless, something that counts as our actual first-person experience, and that this is the ‘self’ we’re referring to here. That is, for whom does touching hand to ankle seem to happen simultaneously? Whether the things making up our experiences are illusions or not, the thing they are deceiving is the finally integrated self van Inwagen is talking about. This is an interesting objection, but one that van Inwagen would have to account for as well, given that it seems to posit the conscious self as a kind of mind’s eye that is the ultimate perceiver of the nervous system’s experiential fragments. This either brings us back to dualism, in which the mind is immaterial, or leads us to what’s known as the homunculus problem, which involves an infinite regress of smaller and smaller material mind’s eyes.
One might attempt to resolve the homunculus problem by observing that consciousness exists in just one part of the brain, and that certain parts of the organism’s nervous system decide what information should be sent there, and when. Such a system, it might be argued, can only exist within a composite organism. Again, I don’t think it works. Above, the right hemisphere of the split brain certainly experiences (so to speak) the spoon, even though when asked what he’s seen, the patient responds, “I don’t know.” This seems to suggest that consciousness is not localized. As do the cases in which patients undergo the removal of their left hemisphere, yet remain conscious and develop the ability to speak.[25. “When only the right hemisphere is left: Studies in language and communication”: http://steinhardt.nyu.edu/scmsAdmin/uploads/006/415/hemispherect.pdf] Right hemisphere removal yields similar results.
Granted, these examples don’t disprove the claim that thinking can only be done by composite organisms. All I’ve done is to challenge what I take to be the key intuition in getting us from cogito to composite. I know that I exist, but it’s not so clear that I exist as a composite rather than as a collection of particles, a certain subset of which operates[26. Perhaps it would be more convincing to argue that each of these subsets is a composite, instead of the organism as a whole.] under the (evolutionarily beneficial) illusion that the collection as a whole constitutes a unified self (an illusion administered by another subset of particles in that collection). An even stronger challenge to this intuition would be to imagine a single organism that contains multiple distinct, and simultaneous instances of “I exist.”
Imagine a person whose left and right hemispheres are kept entirely isolated from one another for a long period of time. By isolated, I mean a complete inhibition of bilateral exchange, so that the person would somehow be perpetually kept in the sort of conditions that made it possible to test the stimuli responses of the split-brain patient. Speech would likely have to be inhibited as well. It seems plausible that, given several years, the two hemispheres would begin to compensate as in the above hemispherectomy cases. Over time, each hemisphere might develop quite sophisticated independent consciousnesses, and even different responses to the same stimuli, particularly if the procedure happened at an early age. One brain might prefer punk to Chopin, while the other brain loves both; or one might crave natto, while the other can’t stomach it. They would share the same nervous system, but inhabit distinct internal worlds.
Would both brains contemplate “I think, therefore I am”? And after thirty years of this, were hemispheric communication re-enabled, what would happen? In speculation of questions such as these, we attempt to explore the borders of consciousness and self within the physical human organism. That is, when we ask for whom the illusion of integrated experience occurs, we now have two selves with which to contend, further challenging the intuition of a unified self that is exactly equal to the unified organism that utters, “I exist,” and that is exactly equal to the parts that compose that organism.
The organicist might respond that it doesn’t matter where, how much, or how integrated thinking is within the organism, so long as thinking is happening, but it seems to me that the question of “where?” does matter. That is, even if consciousness isn’t localized to specific parts of the nervous system, it is always somewhere within the nervous system that consciousness happens. Does this not suggest that a non-composite collection of particles are experiencing consciousness? Or, looked at another way, why don’t the physical borders of where experience happens equal the physical borders of the composite? Thinking doesn’t happen in my foot or spleen, so how can the organicist say for sure that thinking requires the system of an entire organism?
This question of borders seems especially salient in cases where the structure of an organism challenges the idea that organisms are, by nature, clearly individuated and holistically self-contained beings — an idea that surely facilitates the conception of organisms as composites, particularly for us non-universalists.
To contemplate this idea more deeply, envisage the Pando, a colony of quaking aspens considered to be a single organism by virtue of each tree having identical genetic markers, and being connected by a single root system (or so the experts presume). It seems quite a stretch to go from, “I think,” to “therefore those thousands of trees — each of which could survive as an independent organism were it separated from the Pando’s shared root system — are proper parts of a composite.” This is especially if the Pando is indeed a bona fide organism, but suppose it is controversially an organism — a borderline case. It might be tempting to let the organicist off the hook, as we did above when wondering about whether a not-quite dead body still counts as an organism. I set that example aside because I wanted to take on the biggest challenge to the nihilist: the fact that there are certainly living, thinking human organisms. But we can’t do that here, as to ignore borderline cases would facilitate question-begging so that whatever van Inwagen means by ‘organism’ is whatever he means by ‘composite,’ and vice versa. If ‘composite’ and ‘organism’ are to be used interchangeably, we are owed some metaphysical grounding for what it is to be an ‘organism,’ rather than, “that which current science happens to say it is.”
To be fair, van Inwagen might grant that borderline cases aren’t clearly composites, so that it may indeed turn out that not all so-called ‘organisms’ are composites. He can still reasonably claim, however, that all composites are organisms, so long as it’s true that anything that thinks is a composite (presuming, of course, that the Plando doesn’t think). But perhaps we can challenge this response by describing a borderline specimen that’s conscious.
Return for a moment to the aforementioned example of the man who lived two weeks with a continuous flow device, instead of a heart. Were doctors to continue replacing his life-sustaining biological and biochemical processes with artificial ones, at would point would he cease to be an organism while still being conscious?
I agree with van Inwagen that not just any sort of collection of things can result in first-person experience, and thus agree when he denies that the Chinese Room and computers can think.[27. Van Inwagen, 119.] This doesn’t mean, however, that consciousness couldn’t survive the artificial replacement of many, most, or all biochemical processes. But we need not go that far, so long as we keep on hand a good supply of well functioning nervous tissue. I alluded to this above, in the suggestion that thinking might not require an entire organism: it may be that all we need is a living brain and some sort of feed into its sensory pathways (as in the classic ‘Brain in the Vat’ thought experiment). Suppose that this brain-in-vat system is externally maintained by technicians in such a way that the system doesn’t count as an organism according to any current standards. To call such a thing an organism on the basis that thinking is happening, would, again, beg the question. (To be clear, my point here isn’t that van Inwagen will have been proved wrong once brain-in-vat technology is developed, but rather to render less inconceivable the possibility of a thinking non-composite.)
Even more fantastically, consider a conscious being who isn’t a borderline ‘organism’ like the Plando, but whose compositional status is similarly dubious. Suppose that the cells of my body were separated, but were kept alive by some artificial means, so that whatever sorts of exchange needed to happen between them was facilitated by nanotechnology or teleportation. The information normally sent over the corpus callosum might be transported thousands of miles from the particles of the ‘left’ hemisphere to those of the ‘right’ in a split second. It seems difficult to conceive of such a thing as a fused together, singular composite object, even though it would still be a conscious, thinking, experientially integrated, living organism. To suggest that the possibility of such a creature wouldn’t work in favor of the idea that multiple parts can think collectively, solely on the basis that the relations of the creature’s particles satisfy the conditions for being a ‘living organism,’ would be to play too loosely with the concept of restricted composition. It shouldn’t be the case that whatever satisfies our definition of ‘living, thinking organism’ must, as a matter of principle derived from the intuitive force of the cogito, be a composite.
That said, van Inwagen may have no problem with the person whose parts are dispersed across miles. Were we to magnify the parts of any organism, we would see that many of them appear very far from one another as it is. And one’s head and feet are not in direct contact, yet are proper parts of an individual composite. Why should extending that distance matter? Indeed, van Inwagen acknowledges in chapter three that contact or lack thereof between particles should have no bearing on whether they compose anything. I obviously agree with this, though such observations ultimately lead me to accept the non-existence of composites. Similarly, for van Inwagen, vagueness about the significance of contact between supposedly composite particles seems to be among the reasons for his rejection of composition. Except in the case of the thinking organism, of course, because, if it has experience, it must be a composite. But why? He doesn’t explicitly tell us.
The more I consider all of this, the more it seems that, despite van Inwagen’s superb bliger example, his definition of ‘composite’ is one that I don’t understand. Though, admittedly, I find most accounts of composites to be unintelligible, which is why I’m a nihilist about composition. Put it this way, I can’t fathom the idea that, in the region of space disjointedly occupied by the collection of particles of the ‘dispersed person,’ there is one thing that exactly, and disjointly, fills that region of space. And I feel the same way about rocks, airplanes, myself, the Pando, and slime mold.
I’ll conclude by quoting van Inwagen: “I do not suppose that it is possible to prove a philosophical thesis, particularly a far-reaching and radical one.”[28. Van Inwagen, 115.] I think he’s right about that, and I don’t expect that were he to read this paper he’d be converted. In turn, and for whatever reason, I’m not persuaded by his arguments, nor by those of other mereologically inclined thinkers. So, I continue to be a nihilist about composition. Others, such as Ross & Dorr, remain agnostic on these grounds. Perhaps my argument would carry more sway were I to attempt to account for what it means to ‘exist in experience,’ and how this might be the basis for the commonsensical impressions we have about things like mugs and human beings existing as material composites. But I’ll have to leave that for future discussions. In the meanwhile, I’m content with having addressed van Inwagen’s organicism as one step in that direction.