1. Introduction
Some philosophers say that you do not think in the primary or nonderivative sense. Rather, they say some item distinct from you (perhaps one of your parts or something of which you are a part) does your thinking for you; you inherit your mental life from that item. In this paper, I argue that this is a mistake. We do not inherit our thoughts in this way.
I proceed as follows. First, I identify a Priority Principle according to which we exhibit certain of our properties in the primary or nonderivative sense. I motivate the principle with an argument and then demonstrate its consequences in the metaphysics of human persons. As it turns out, the principle is inconsistent with certain views in the metaphysics and philosophy of mind. Along the way, I will identify certain philosophers who endorse views at odds with the Priority Principle. One lesson from this exercise is simple; those philosophers are wrong (at least, they have endorsed views with implausible consequences). But my overall aim is more general. I wish to show not just that a few philosophers have been wrong, but to pave the way for progress in the metaphysics of human persons by showing that all views like theirs come at a substantial theoretical price. For those unwilling to pay that price, such views are dead ends.
2. The Priority Principle
I have many properties. I am more than four feet tall (though I was once much shorter). I believe that Sydney is a city. I am seated. I am thinking about metaphysics (hopefully, you are too). Or so it seems.
One sometimes hears of a distinction between derivative and nonderivative ways of having properties. Certain items have properties in a primary or nonderivative sense, we’re told, while other things enjoy those properties only derivatively or by proxy. Smokey's toe is over the line in the primary or nonderivative sense; and so Smokey himself is over the line in a derivative or secondary sense. Smokey enjoys this distinction by proxy and only because he is related to his toe in some special way (by parthood, in this case). With this distinction in mind, we may say I bear the features discussed above in the primary or nonderivative sense. Whatever it is I am, I am a thing that bears each of these features and not by way of any proxy. It is me, and not merely some proxy or stand-in for me that is hungry, that is more than four feet tall, that believes Sydney is a city, and the like. So Trenton Merricks:
I think that when you look in a mirror, or down at your hands, you can actually see yourself. And when you hold your child, you do exactly that—hold the child himself or herself—and not some stand-in. . . . Objection: we see a non-physical person by seeing her body. Response: this sense of seeing a person is secondary, parasitic on the primary sense in which we see her body; but I say we see persons in the primary sense. (Reference Merricks2001: 85).
I have listed various features and claimed that I have them in a primary sense. In this, I am not alone. You may not believe that Sydney is a city, but you do believe something or other. You are (I hope!) thinking about metaphysics. And you are probably more than four feet tall.
Mental features have a place of privilege when thinking about the metaphysics of thinking beings like you and I. They figure into the content of the question of what we are. To ask ‘What are we?’ is, among other things, to inquire into the nature of the subjects of our thoughts. For what are we but the subjects of our thoughts, the things that think them? And while it may turn out that we have certain physical properties (like having a mass) in only a derivative sense, saying the same about our mental properties is much less plausible. It seems (to me, at any rate) forcefully clear that I think in a primary sense. And so do you. More generally: if there is an ordering to the numerically distinct things thinking our thoughts, we come first. We enjoy a kind of priority. Thus Roderick Chisholm:
Hoping for rain is one of those properties that are rooted only in the times at which they are had. And so if I am an ens per alio, an ens successivum, like our simple table or the Ship of Theseus, then I may be said to hope for rain only in virtue of the fact that my present stand-in hopes for rain. I borrow the property, so to speak, from the thing that constitutes me now.
But surely that hypothesis is not to be taken seriously. There is no reason whatever for supposing that I hope for rain only in virtue of the fact that some other thing hopes for rain—some stand-in that, strictly and philosophically speaking, is not identical with me but happens to be doing duty for me at this particular moment.
If there are thus two things that now hope for rain, the one doing it on its own and the other such that its hoping is done for it by the thing that now happens to constitute it, then I am the former thing and not the latter thing. (Reference Chisholm1976: 104)
Though Chisholm's remarks are supposed to tell against one early version of the doctrine of temporal parts, I maintain that they have general application. I propose then, the following:
priority principle. We human persons have mental properties (like hoping for rain) in the primary and nonderivative sense. We think our thoughts in the primary and nonderivative sense.
This principle is independently plausible, but I shall also argue for it. Before so arguing, I’ll offer some remarks that I hope will clarify its content. The Priority Principle, has it that our thoughts are not derivative. But there are various ways in which thoughts might be derivative. Which kind of derivativeness is the Principle supposed to exclude? This is a good question. Perhaps the best answer I can give is to state what the Principle does not mean. On my preferred reading of the Priority Principle, it is not at odds with the following claims:
1. We think because of the nonmental features of something(s) distinct from us (whether our tiniest parts, the world as a whole, or something else besides). Example: we think because certain parts of our brains—neurons, say—exhibit certain structures or firing patterns.
2. We think because of the mental features of something(s) distinct from us (whether our tiniest parts, a Berkeleyan god, or something else besides). Example: we think because our tiniest parts are themselves proto-conscious (or whatever kind of mentality it is that panpsychists think our smallest parts exhibit).
3. We think because we are embedded in a certain social framework that makes possible both our existence and our having sophisticated and reflective mental lives.
4. We think because our evolutionary history has endowed us with certain complex powers (among which are the abilities to reason and feel in various ways).
These sentences—if they express anything at all—express ways in which our thoughts might be derivative. But they are not at war with the Priority Principle. The Priority Principle's main rivals, instead, are: that we think our thoughts because something else thinks our thoughts for us; that we are not the subjects of our de se thoughts; that we ‘borrow’ our mental properties, that we think our thoughts only by proxy, and so forth.
3. An Argument for the Priority Principle
I have stated the Priority Principle and said it seems true. I will now argue for it. In a nutshell: you and I have mental lives; we think thoughts. That's the realism component of my argument. We also have mental lives not enjoyed by anything else (anything else in our immediate vicinities, at any rate). There is exactly one thing thinking my thoughts, for example, and exactly one thing thinking yours. That's the uniqueness component of my argument. Together with two plausible premises, these components imply the Priority Principle. I will put the argument in the first person singular, but the argument generalizes and so supports the Priority Principle. And though I will put the argument in terms of ‘thinking my thoughts’, we could just as easily put the argument in terms of exemplifying certain mental properties. Here is my argument:
D1. I, in some sense or other, think my thoughts.
D2. If I, in some sense or other, think my thoughts, then either I think them in the secondary and derivative sense or I think them in the primary and nonderivative sense.
D3. If I think my thoughts in the secondary and derivative sense, then there are two things thinking my thoughts.
D4. But there are not two things thinking my thoughts.
C. Therefore, I think my thoughts in the primary and nonderivative sense (from D1–D4).
Thus the Priority Argument. It is valid. Are its premises true? It seems so. (D1) is an expression of realism about mentality. (D2) is an expression of the primary/secondary distinction. My argument for (D3) is as follows:
Either thinking my thoughts in the secondary and derivative sense is a way to think my thoughts or it is not. If thinking my thoughts in the secondary and derivative sense is not a way to think my thoughts, then if I think my thoughts in the secondary and derivative sense, then I do not think my thoughts. But I do think my thoughts. Therefore, thinking my thoughts in the secondary and derivative sense is a way to think my thoughts. If thinking my thoughts in the secondary and derivative sense is a way to think my thoughts, then if I think my thoughts in the secondary and derivative sense, then there are two things thinking my thoughts. Therefore, if I think my thoughts in the secondary and derivative sense, then there are two things thinking my thoughts.
And (D4), finally, is an expression of uniqueness; there aren't a plethora of beings thinking my thoughts. Indeed, there aren't even two.
I have said something about the intuitive case for the priority principle. The Priority Argument shows that these intuitive considerations do not stand alone; there are other intuitive considerations that also tell in favor of the Principle. But make no mistake; running afoul of the Principle does not simply raise a familiar ‘problem of too many thinkers’. It is not as though rejecting the premises of the Priority Argument is the only price one pays in denying the Priority Principle. For suppose that there are, after all, a multitude of beings thinking my thoughts (where the host of thinkers is ordered, and where one member thinks those thoughts in the primary and nonderivative sense). It would be a mistake to identify me with any member of that host but the one who enjoys this priority. Perhaps we can make peace with the existence of such a host of things thinking my thoughts, but we can only do this by identifying me with a special member of that host.
I conclude, then, that the case for the Principle is strong. It is a desideratum (though perhaps not an invulnerable one) regarding metaphysical theories that they respect the Principle. It is of interest, then, to see which metaphysical theories run afoul of the Principle.
4. The Principle Applied
Some views are inconsistent with the Priority Principle. Chisholm applied the Priority Principle only to an early version of the doctrine of temporal parts; I will show that the Principle is of even wider import. In this section, I will discuss a few target views, show how they are inconsistent with the Principle, and thus illustrate the costs of adopting such views.
4.1. Thinking Material Parts
Some metaphysicians and philosophers of mind say things that suggest they endorse the conjunction of the following two theses:
1. Some proper part of my body thinks my thoughts in the primary and nonderivative sense.
2. I am not identical with any proper part of my body.
Let us call this conjunction the ‘thinking material parts view’. Candidate proper parts of my body—things that might think my thoughts for me—include my brain (or perhaps my nervous system, or perhaps a proper part of my brain, such as my cerebrum). It is these parts of my body that are said to think my thoughts in the primary and nonderivative sense. I inherit or somehow derive these thoughts from my parts; I think them in the secondary and derivative sense. Says Ingmar Persson:
Strictly speaking, it seems that it is not the whole human body that is the owner of experiences. The owner is rather its brain, or even certain parts of the brain, for these are what is minimally sufficient for the occurrence of the experiences. It is nomologically possible that a stream of experiences continues, even though almost all of a human body is annihilated, as long as certain cerebral parts are kept alive in certain states. The fact that the body possesses experiences is therefore derivative from their being possessed by proper parts of it: the body has experiences in virtue of having certain proper parts that primarily have them (i.e., that have them, but not in virtue of having any proper part that in turn has them). (Reference Persson and Strawson2004: 35)Footnote 1
Philosophers like Persson are not brainists; they do not think we are our brains. Instead, they say that our brains (or nervous systems or cerebral hemispheres) are parts of us and do our thinking for us. The thinking material parts view does not have the obviously false consequence that we do not think. Rather, it has the consequence that we think in a derivative or secondary sense. We think because we are appropriately related (in this case, by the having as a proper part relation, perhaps among others) to things that think in the primary and nonderivative sense.
But the thinking material parts view is a mistake. For one thing, this view implies that two entities think my thoughts—me, on the one hand, and, say, my brain, on the other. Worse (and this is the point I want to emphasize), this view implies that I do not think my thoughts in the primary and nonderivative sense. It is inconsistent with the priority principle.
4.2. Union Dualism
Some philosophers maintain that it is not my brain, or any other material part of me, that thinks my thoughts in the primary and non-derivative sense. Rather, it is some immaterial (proper) part of me that does so. Union dualism, let us say, is the conjunction of the following three theses, which should be read as applying in the ‘ordinary’ case (in particular, they do not apply to human beings who are dead):
1. Human beings have both wholly immaterial and wholly material parts (among which are a body and a soul).
2. The wholly material parts of human beings have physical properties (like being over five feet tall) in a primary or nonderivative sense. Human beings have such physical properties in a secondary or derivative sense (and by virtue of having those wholly material things as parts).
3. The wholly immaterial part of a human being has mental properties (like hoping for rain) in a primary or nonderivative sense. Human beings have such mental properties in a secondary or derivative sense (and by virtue of having those wholly immaterial things as parts).
Union dualism is to be contrasted with Cartesian dualism, according to which each human being just is a wholly immaterial object. One representative of union dualism is Richard Swinburne:
Those persons which are human beings (or men) living on Earth, have two parts linked together, body and soul. A man's body is that to which his physical properties belong. If a man weighs ten stone then his body weighs ten stone. A man's soul is that to which the (pure) mental properties of a man belong. If a man imagines a cat, then . . . his soul imagines a cat. . . . On the dualist account the whole man has the properties he does because his constituent parts have the properties they do. I weigh ten stone because my body does; I imagine a cat because my soul does (Swinburne Reference Swinburne1997: 145).
John Foster may also be a union dualist. Foster distinguishes between basic and nonbasic mental subjects (Foster Reference Foster1991: 203). Basic mental subjects bear mental properties (and think thoughts) in the primary or nonderivative sense. Nonbasic mental subjects, on the other hand, bear mental properties (and think thoughts) in the secondary and derivative sense and by virtue of their relation to basic mental subjects. According to Foster, all basic mental subjects are wholly immaterial beings (204).
Among these basic mental subjects are our minds. So our minds are wholly immaterial beings. But what about us? What about human persons? Are we basic mental subjects and thus wholly immaterial? Foster does not endorse any answer to this question; he claims that our concept of a human person does not settle the question and that we are free to use whatever concept of a person we like (Foster Reference Foster1991: 239–40) But he thinks there is some pressure to say ‘no’. For ordinary thought and speech certainly seems to treat human persons as both mental subjects in some sense and as corporeal beings (and, indeed, as animals) (Foster Reference Foster1991: 203, 239). This would suggest, then, that human persons are nonbasic mental subjects; for that is the only way for a corporeal being to be a mental subject at all. In other words, this would suggest that we think our thoughts in the secondary and derivative sense, by being appropriately related to wholly immaterial things (our minds) that do our thinking for us in the primary and nonderivative sense. Perhaps this ‘appropriate relation’ is not parthood (as on Swinburne's view). In that case, Foster would not be a union dualist. But he would, nonetheless, endorse the view that we think in the secondary and derivative sense. And that view, after all, is the one I’m targeting in this paper.
Union dualism is inconsistent with the Priority Principle and clearly so (Olson [Reference Olson and Corcoran2001] offers a similar objection to union dualism but doesn't draw the more general morals of the story as I do in this paper). For union dualism has it that, strictly speaking, you and I do not think in the primary sense. Rather, we have parts that think for us, and they think in a derivative sense; we think by virtue of having nonmaterial thinking parts. I have cited Swinburne and Foster, but I do not intend to merely point out that two Oxford philosophers have held a false or costly view. My point is more general. Any version of union dualism according to which we think by virtue of having as parts souls that think in the primary sense is vulnerable to this objection. So much the worse for those views.
4.3. Hylomorphism
Aristotle famously claimed that certain objects are composed of form and matter (Metaphysics VII 8.1034a5-6, Metaphysics VII 8.1033b23-25, Metaphysics VII 11.1037a29-30, Metaphysics VII 15.1939b20-25, and Metaphysics XI 9.1058b80-12.) This doctrine—hylomorphism—has enjoyed something of a renaissance in recent decades (see, e.g., Fine Reference Fine1999; Johnston Reference Johnston2006; and Koslicki Reference Koslicki2008). I will here examine one application of hylomorphism and argue that it too runs afoul of the priority principle. Jeffrey Brower has argued that hylomorphism offers a compelling solution (henceforth, ‘the hylomorphic solution’) to the problem of temporary intrinsics.Footnote 2 Says Brower:
Ordinary objects persist through intrinsic change by successively entering into larger wholes of which they and their temporary intrinsics are proper parts or constituents. Moreover, it is only these larger wholes which have the relevant properties simpliciter, whereas ordinary objects come to have these same properties only by entering into such wholes as parts. Thus, in the particular case of Socrates, an enduring object (namely, Socrates himself) derivatively possesses the properties of bentness and straightness at different times solely by successively being part of two distinct objects (namely, Socrates at t 1 and Socrates at t 2, respectively), which possess these properties in the primary or proper sense (Brower Reference Brower2010: 889).
Suppose some persisting thinking thing (I volunteer) hopes for rain for but a few minutes and ceases to so hope after rain begins to fall. I existed before hoping and continue to exist after. Finally, hoping for rain, let us suppose, is a temporary intrinsic property. According to the hylomorphic solution, something having me and the property hoping for rain as parts—call it ‘hoping-me’—lasts just so long as I hope for rain, and it hopes for rain in the primary sense. I enjoy the distinction of hoping for rain in a secondary or derivative sense by being a part of hoping-me. But hoping-me is numerically distinct from me. So it is something numerically distinct from me that hopes in the primary sense. And the same goes for each of my mental temporary intrinsic properties. But then it is not me that thinks my thoughts in the primary sense. It is something else. And thus I conclude that the hylomorphic solution is at odds with the Priority Principle.
4.4. Constitutionalism
Some philosophers insist that while we are not identical with animals, each of us is constituted by an animal. We are not animals in the primary or nonderivative sense, but each one of us is appropriately related to an organism that is. The appropriate relation in question is that of constitution. Indeed, this is how we have any of the physical properties we do—by being appropriately related to an organism having that property in a primary or nonderivative sense. Thus Baker:
The idea of having properties derivatively explains how, say, I can have the property of being overweight. It is not just that my body is overweight; I am. Being overweight is a property that I—the person constituted by this particular body—have. True, being overweight is a property that I have because my body has it, but my body constitutes me. So, I have the property of being overweight derivatively (Baker Reference Baker2000: 99).
Constitutionalism says, then, that we have physical properties, but we have them derivatively. The same goes for the property being an animal. We do not enjoy biological properties in a primary or nonderivative sense. Rather, we are each constituted by something that does. Thus described, constitutionalism is consistent with the Priority Principle. But Lynne Rudder Baker's version of the view is not. For according to Baker, we have certain of our mental properties in the secondary and derivative sense (while the animals that constitute us have them in the primary and nonderivative sense). In particular, we derivatively have mental properties that do not require a first-person perspective. So Baker:
The idea of having properties derivatively also applies to mental properties. For example, many of the pains that I have are such that dogs and other mammals could have pains of the same types. If my pain is of a type that a dog could have, then it is one that I have derivatively . . . some of my mental states (e.g., being in pain of certain kinds) I have derivatively; other of my mental states (e.g., hoping that I will not be in pain on my birthday) I have nonderivatively (Baker Reference Baker2000: 100–101).
As seen above, Baker is clear that we have some of our mental states in the primary and nonderivative sense. But this does not pay sufficient respect to the Priority Principle. Consistency with that principle requires that we think all our thoughts and have all of our mental states in the primary and nonderivative sense. And this is something Baker's view does not allow.
5. Endgame
Philosophy is like chess. There's an opening. There's a middlegame. And there's an endgame. In the opening, we learn what the basic answers to a given question might be. In the middlegame, we detect what options those answers leave open (and which ones they close); we also get a sense of the theoretical costs and benefits of those answers. And in the endgame, we see how those theoretical costs and benefits stack up in some final reckoning (and, one hopes, land closer to truth). This paper has largely been an exercise in opening and middlegame philosophy. Thus far, I have identified a family of views with one feature in common. I have, further, argued for an attractive Priority Principle, argued that the family of views is inconsistent with that principle, and claimed that this is a substantial theoretical cost for all such views.
But what of the endgame? Should one, in light of the arguments of this paper, reject all inheritance views and stand instead with the Priority Principle? That is an option. And for those convinced thus far, the lesson is simple: do not endorse the thinking material parts view, union dualism, the hylomorphic solution, or Baker-style constitutionalism. Indeed, do not endorse any view according to which we inherit our thoughts and think them only in a secondary or derivative sense. Whatever their other merits may be, these views have a very implausible consequence. And so they—and all views like them in that respect—should be rejected.
Philosophers are a clever (some would say stubborn) lot, though, and many will be unpersuaded by my remarks, perhaps opting instead to endorse an inheritance view. The lesson for these philosophers is a little different. They must deny the Priority Principle, of course. And that comes at some cost, I’ve claimed. Is the cost too high? Is it, on balance, one not worth paying? These questions are difficult, and I do not claim that my preferred answers (‘yes’ and ‘no’, respectively) are by any means obvious. But here is an important factor to consider: I haven't merely identified the Priority Principle and claimed it seems true. Instead, I have offered a valid argument for the Priority Principle. So the proponent of, say, the thinking material parts view must do more than just deny the Priority Principle. She must also deny one or more of the premises of my argument. And here's the rub. Those premises certainly seem compelling. It certainly seems as though I think, for example, and it certainly seems as though I am the only thing that thinks my thoughts. Even if I’m wrong about the status of these theses (and the other premises of the Priority Argument), I have shown this much: their fate is interestingly connected to that of the Priority Principle and to that of the various views that conflict with it. Philosophers who wish to maintain those views have their work cut out for them. That work would, I propose, include a diagnosis of exactly where my argument for the Priority Principle goes wrong and either some indication of why rejecting its premises is not, after all, a costly affair or an argument that the price is worth paying.
Thus, a few remarks about the endgame implications of this paper and its arguments. Those implications are largely negative; they suggest that a family of views is to be avoided. Are there any positive lessons to be drawn here? Can we use what we have learned here to make headway in the metaphysics of human persons and perhaps in metaphysics more generally? I believe we can. For there are a number of views that do not conflict with the Priority Principle. These views deserve our attention. I will quickly point to two such views (I favor the first):
1. Animalism. We are human animals, and as such we are living, breathing, wholly material beings. But it is not our brains (or any other items distinct from us) that think for us. Rather, we human animals think in the primary and nonderivative sense.
2. Cartesian dualism. We are wholly immaterial, thinking beings—souls. Our souls are not—contra union dualism—parts of us. Rather, we are our souls. And we souls think in the primary and nonderivative sense.
Animalism and Cartesian dualism respect the Priority Principle; they pass one important hurdle. This counts in their favor, at least over the other views I’ve considered in this paper. We would do well to consider them carefully, for one of them may well be the sober truth.