11.4—
Psychology, the Mental, and Causal-Nomological Explanation

First, consider the issue of whether intentional psychology can be made into a causal-nomological science. This issue concerns the dialectic between (a ) the actual form of our understanding (both commonsensical and scientific) of mental states and processes and (b ) the prevailing view that scientific discourse is causal and nomological in character. There are really two separate issues here, of course, though they tend to get conflated: (1) the issue of whether there can be a psychological science that is causal and nomological in character, and (2) the issue of whether entry into nomic causal relations is relevant to ontology . The relationship between science and ontology will be discussed later. Here I shall concentrate on the dialectic between the causal-nomological picture of science and the actual state of our discourse about the mental.

There are two basic ways of coming to the conclusion that intentional explanation cannot be causal explanation based on causal-nomological regularities. The first way is to think that intentional explanation is part

and parcel of an enterprise called "folk psychology" which is an attempt at protoscientific explanation of behavior, and then conclude that it fails in its attempt to capture causal regularities in the intentional vocabulary. This view that commonsense intentional psychology is an attempt at causal-nomological explanation, sometimes called the "theory-theory," is fairly prevalent in cognitive science circles. It will be discussed in the following section. Before turning to it, it is important to see that there is also another way to come to the conclusion that intentional explanations cannot be causal-nomological explanations: namely, to believe that they were never intended as such in the first place .

11.4.1—
The Verstehen Argument

The claim that mentalistic discourse does not even attempt to provide causal explanations has had important advocates in both the analytic and the continental traditions. It includes the Verstehen tradition in the Geisteswissenschaften on the continent, Ryle and Wittgenstein, and lately a related sort of view has attracted interest from analytic philosophers like Alvin Goldman (1992, 1993a, 1993b,). On this view, intentional explanation involves giving reasons, and giving reasons is different from giving causes. The kind of "explanation" we are involved in when we allude to people's beliefs and desires is not causal explanation, but something like interpretation . The goal of investigation framed in the intentional idiom is not knowledge of general laws of thought, but in Verstehen, or interpretive understanding, of human beings.

In a certain way, I am very sympathetic to this view, especially in the ways in which it stands in contrast to the theory-theory. It is no doubt true that "commonsense psychology" involves a "theory" in the weak sense that we make generalizations about how people are likely to think and act, and that these expectations, were we to express them, would be expressed in the intentional vocabulary. But it seems a bit dubious to equate this with an attempt to formulate causal laws, and very highly questionable to refer to intentional states as "theoretical entities" as that expression is sometimes used in the philosophy of science (i.e., to signify entities posited through a process of retroduction). Particularly when we refer to dispositional states such as beliefs, it seems quite reasonable to say that what we are doing is trying to paint a picture of the person's thoughts that makes sense of their words and deeds, and it would be somewhat strained to say that we are trying to provide the causes of their

actions, much less that we are tacitly assuming universal laws formulable in the intentional idiom.

Nevertheless, it seems important here to separate two very different sorts of issues. We might, on the one hand, concentrate on issues relating to the nature of commonsense intentional psychology. On the other hand, we might undertake quite a different sort of inquiry into the prospects for a causal-nomological intentional psychology. It is useful here to distinguish four very different questions:

(1) Is the theory-theory an accurate representation of the nature of commonsense psychology? (That is, is commonsense psychology really an attempt at a scientific theory based on causal laws?)

(2) Is there a viable enterprise of interpretive psychology whose goal is Verstehen?

(3) If so, should we call it "science"?

(4) Is there a viable causal-nomological psychology that makes use of generalizations at the level of cognitive states and processes?

The reason that it is useful to separate these questions is that the answer to the fourth question—our main focus here—is really quite independent of the answers one gives to the other three. In point of fact, I think that one might have to give a somewhat mixed answer to the first question, since the characterization of commonsense views is likely to be a somewhat complicated undertaking; but I am inclined to side more with Ryle and Wittgenstein here than with the theory-theory. I take it that the second question can best be answered by looking at what is accomplished by attempts at interpretive psychology (e.g., psychoanalysis as interpreted by Ricoeur [1970]) in the long run. The third question is in large measure a matter of wrangling over words. In some ways, I think the German approach has some real advantages: if you have two categories of Wissenschaften you can then ask serious questions about how they differ; whereas if your distinction is between "science" and "nonscience," there is an unfortunate tendency to assume that everything that is nonscience is also nonserious and nonrigorous, and that all such enterprises are nonserious and nonrigorous in the same ways. All in all, though, I find this fight less interesting than I used to, and do not intend to belabor it here.

What seems crucially important here is that the viability of a causal-nomological intentional psychology is in no way threatened either by the

possibility of interpretive psychology or by the possibility that commonsense psychology is not accurately conceived of as protoscience. One might demonstrate this point by way of a thought experiment. Suppose, for example, that someone were convinced by writers like Wittgenstein and Ryle that the "because" of intentional explanation (in ordinary usage) is not the "because" of causation. Suppose, furthermore, that she believed that ordinary intentional explanation was part of a project of interpretive understanding (Verstehen ), and that there were disciplines—the Geisteswissenschaften —that attempted to approach such interpretative understanding in a systematic way. She might think, for example, that Ricoeur's Freud was an active and even an occasionally successful practitioner of such a discipline. Suppose now that one day she comes across something like Colby's (1975) attempts to implement models of Freudian theories in the form of computer programs. Upon examining these she might well feel that she has discovered a new possibility for explanation in the intentional idiom: in addition to the possibility of an interpretive psychology, it might be possible to systematically explain causal relationships among intentional states as well. It might even turn out that there are important connections between them—for example, that rules for deriving new cognitive state tokens are so formed as to preserve truth and maximize coherence and relevance. Our fictitious person could thus discover the idea of a nomological intentional psychology as a project quite orthogonal to commonsense psychology and interpretive psychology, but in no way in competition with them.

What I think this shows is that neither the Ryle-Wittgenstein view of intentional explanation nor the Geisteswissenschaft approach to psychology should be viewed as counting against the viability of a nomological intentional psychology. These views would, of course, undercut the claim that the success of commonsense psychology in allowing us to predict one another's behavior in day-to-day affairs provides direct evidence for the possibility of a nomological intentional psychology. But it need not rule out providing such evidence more indirectly: if we are successful at interpreting others, it might be in part because we have a kind of model in our heads of how people are likely to think and act given certain beliefs and desires, and this at least suggests the possibility of a nomological account of how different beliefs and desires in combination will produce other cognitive states and, ultimately, behaviors. In short, even if "folk psychology" is a dubious philosophical reconstruction, this does no fundamental damage to the project of nomological intentional psychology.

11.4.2—
Intentional Categories and Causal Relevance

Establishing compatibility between causal explanation and Verstehen (as two separate projects), however, is the easy part of the job. The hard part lies in making a case that intentional psychology is susceptible to being made into a "science" in the prevalent usage of the word in America, where it suggests a causal and nomological character. One important problem lies in the fact that intentional psychology individuates its objects semantically. But if it is to be a science, one would wish for the individuation of terms to take place in a fashion that captures causal regularities: if a belief that a cat is in the yard is used to explain different behaviors than a belief that a unicorn is in the yard, and we are talking about a kind of causal explanation, we should expect the difference in the causal powers of the two beliefs to be intimately connected to their difference in content. But it is hard to see how this might be the case, and it has generally seemed that there are only three basic possibilities: (1) there is some interpreter that is sensitive to semantic properties and is also the locus of the causal powers, (2) semantic properties are themselves causally efficacious, or (3) semantic properties are linked to some other kinds of properties that are causally efficacious. The problem with (1) is that it leads to a homuncular regress. The problem with (2) is that semantic properties just do not seem like things that have causal powers. The computer paradigm takes option (3) with respect to semiotic-semantic properties, which are unproblematically linked to nonsemantic properties through interpretive conventions, but it is not clear how mental-semantic or MR-semantic properties might similarly be coordinated with some other properties that are causally efficacious, or what those properties might be.

The issue here is one of trying to see how something might be the case —that is, how it might be that causal regularities of cognition could run parallel to semantic properties of cognitive states. And the issue of "seeing how X might be the case" shapes up very differently depending on what kind of evidence we have that X actually is the case. For example, many people in Newton's day (and perhaps many of us today) found the picture he presents of gravitation to be problematic because it involves action at a distance. The familiar paradigm of causal interaction had long been one of contact interaction, and it seemed—indeed, it still seems—hard to see how bodies could exert influence somewhere they are not. This difficulty in seeing how it could be so might have been seen as a compelling argument against causation that does not involve contact

interactions, except for the fact that there was overwhelming evidence that such causal influence did take place. (Indeed, of the fundamental "forces" posited by contemporary physics, none of them aside from mechanical force involves contact interaction.)

I think that the same kind of benefit could, in principle, accrue to psychology: if there were to emerge an intentional psychology framed as a set of laws governing reasoning, and it had a sufficient degree of predictive accuracy, this would provide strong evidence that intentional states do have the kind of causal role assigned to them by such a theory. And it would provide such evidence regardless of whether we can see a mechanism that could account for such causation . The particular form of intentional causation could be fundamental, after all, like the particulars of gravitation or electromagnetism or of why particles behave in the precise way they behave when they collide. Or intentional causation could be opaque to us without being fundamental—it could be that we can have evidence that there are causal regularities at the level of intentional explanation, and it might also be the case that these are emergent out of some more basic kinds of regularities without our being able to know just what the relationship between levels is. (Even if computational formalisms are appropriate for psychology, it seems all too likely that we shall never know the details of interlevel relationships in detail.) In such an eventuality, its status would be not unlike that of Newtonian description of gravitational attraction, which supplied a nomological description (and hence conferred mathematical maturity) without explaining this behavior by positing an underlying mechanism (and hence did not supply additional connective maturity).

The first part of the answer to the second objection to intentional psychology, then, is this: computational psychology provides one of the first chances we have really had for making any realistic attempt at building nomological theories of cognition that treat intentional states as causally relevant in reasoning and behavior.^[2] The programme is relatively young, and any possible model of the mind rich enough to test for predictive accuracy with respect to cognition would necessarily be orders of magnitude more complex than most of the fundamental laws in other sciences.^[3] (Though many researchers seem to think that some of the initial results seem promising.) The obvious moral to draw is that we ought to let cognitive psychology mature as best it may, and see whether it does provide compelling evidence that semantic properties of intentional states seem to be at least correlated with causal regularities.

There is also a second response to this objection—one that draws more

directly upon what is made explicit in BCTM. BCTM makes a fairly bald-faced assertion to the effect that intentional states are realized through naturalistic properties in a systematic way, such that (a ) intentional modality is realized through functional relations and (b ) mental-semantic properties are realized through some naturalistic properties (labeled "MR-semantic properties" until their true identity is discovered) possessed by cognitive counters. And it is important not to be fooled by the "semantic" in 'MR-semantic'. Remember that all 'MR-semantic properties' means is "those properties of cognitive counters, whatever they turn out to be, through which content is realized." In particular, the "semantic" in 'MR-semantic' is not so robust that our intuitions that "semantic properties" cannot be causally efficacious should transfer to MR-semantic properties. MR-semantic properties, if they are anything at all, are just naturalistic properties whose real identity we have not discovered, and so they seem perfectly respectable as possible explainers of causal regularities (though whether they capture the right regularities to make our intentional explanations into causal laws remains to be seen). If the research programme associated with BCTM can be carried out, then there will be a causal, nomological science to be carried out, at least at the level of the realizing system . That is, the system of cognitive counters will have lawlike causal regularities, and the MR-semantic properties through which mental-semantic properties are realized will be at least correlated with the causal properties of the cognitive counters of which they are the properties.

The difficulty here is this: the level of description for the realizing system is not a level of psychological description per se. What can the causal, nomological character of the realizing system show us about the realized system, the system of intentional states and processes? Does the causal, nomological character of the realizing system automatically accrue to the system it realizes? Or does it, perhaps, suggest that the realized system also has such a character? There are, I think, two parts to the answer. First, even if we could not construe the system of intentional states and processes as a causal and nomological system, it would matter a great deal if we could show that this system is realized through a system that did have these virtues. For example, if there were overwhelming Rylean objections to interpreting intentional states as being even the sorts of things that can enter causal relations, the psychologist can at least take heart at the news that there is some other system of states and properties—those through which intentional states and processes are realized—that can enter into such relations, and moreover, that whenever one picks

out intentional states and processes, one picks out the states and processes through which they are realized as well. (If you go to the racetrack, you can bet on the horse or bet on the jockey on the horse; they win or lose together!)

But I think one can make a case that at least some of the properties of the realizing system can also accrue to the realized system as well. Take our example of the Victoria Crown. The property of being the Victoria Crown is realized through a particular bit of matter. Let us say it weighs fifty pounds. Now there is nothing about the property of being the Victoria Crown that entails weighing fifty pounds. But the object that is the Victoria Crown does weigh fifty pounds, and does so because the matter of which it is composed has that mass. This property of the realizing matter accrues to the realized object as well. Similarly, suppose Jones's generosity is realized through his giving $100 to the Presiding Bishop's Fund for World Relief on Pentecost. The act takes place at a particular time and has a particular beneficiary. Now we should not say that Jones's generosity is an event taking place at a particular time, but we might say that it was exercised at a particular time. And we should surely say that the Presiding Bishop's Fund was the "beneficiary of Jones's generosity" and not just the recipient of $100. So it seems that, at least in some limited ways, the realized system can take on some of the properties of the realizing system. (It does not follow, of course, that the properties of the realizing system accrue to the realized property —the property of generosity does not take on new implications because of how it is realized.)

A detailed examination of the various possible relations between realizing and realized systems would probably require some very careful metaphysical investigation. It seems quite reasonable, however, to suppose the following: if (1) a mental state X of type M is realized through a natural state of type N , and (2) it is a law that N 's cause O 's under condition C , and (3) C obtains, then (4) an O will come about, and (5) X may be said to be a cause of O . (And this holds even if we do not say "X is an N " but only "X is realized through an N -token.") Here the causal powers of the instantiating type N accrue to the realized individual X , but not to the realized property M .

Now none of this precludes the possibility of saying that intentional states have causal powers in their own right, and not just by virtue of how they are realized. The point is merely that, if computational psychology as described by BCTM can be carried out at all, there will be some naturalistic system through which intentional states and processes are realized, and this system can be causal and nomological in ways that

are not at all problematic. If there are problems about intentional and semantic properties being of the right sort to ground causal regularities, perhaps this gap can be filled by way of appeal to the realizing system.

To summarize, there really are some prima facie difficulties with the attempt to construe intentional explanation as lawlike causal explanation, and hence to make intentional psychology into a "science" in the sense of the word that implies such causal lawlike explanation. The issue of the nomological character of intentional explanation, however, is best settled by letting the project of intentional psychology, supplemented by resources of the computer paradigm, flourish as best it may and seeing whether the project will pan out in the end. And if it does produce what look like nomological regularities, this in itself provides substantial warrant for suspecting that these regularities are causal in nature as well, whether or not we can find or even imagine an underlying mechanism that could account for the causality . In any case, if BCTM can be carried out, there will also be a system describable in wholly naturalistic terms through which the system of intentional states and processes is realized. And this system (a ) can unproblematically be viewed as causal in nature, (b ) is in one-to-one (or even many-to-one) correspondence with the system of intentional states and processes, and (c ) may even confer its causal properties upon the things it realizes.

11.4.3—
Need Mentalistic Discourse Be Scientific to Be Legitimate?

To tell the awful truth, though, I have my doubts about whether there can be a causal-nomological science of the intentional. Apart from all the problems in formulating actual theories with so many hard-to-isolate, mutually dependent variables, I share the Wittgensteinian suspicion that ordinary-language belief ascriptions are not causal explanations; and hence, whatever a computational psychology might do, it would not render whatever ordinary language is doing in such cases scientific, but add a new kind of discourse, perhaps only loosely inspired by the original. I also believe in free will, which seems in tension with a thoroughgoing nomological psychology. There are also other reasons that I find harder to articulate. But none of this makes me doubt the existence or legitimacy of mental states . And this is because I do not think that the considerations that exclude an object from a specifically scientific ontology (i.e., the domain of a science) exclude it from ontology generally. I will discuss some parts of this issue here and others later in the chapter.

First, different kinds of discourse have different purposes, and the conditions for legitimation for a given kind of discourse vary with its purpose. The natural sciences aim at describing and explaining the regularities of nature. The good-making qualities of the natural sciences are thus conditioned by the practical constraints governing what counts as a good enough explanation, the need for truth-conditional evaluation, and the availability of real regularities to be found in nature. Most of our human discourses, however, have different sets of constraints. Many speech acts do not have truth conditions at all, but other kinds of felicity conditions (see Austin 1962; Searle 1969). Indeed some entire language games may lack truth conditions, though of course they have felicity conditions of some kind. For example, if two people play mental chess, saying "King to Queen one" constitutes a move, not an assertion. Now some people would go so far as to think that mental state ascriptions are similarly nonassertoric. And perhaps some mental state ascriptions are not assertions and do not have truth conditions. But I think many of them are assertions and are subject to truth-conditional evaluation.

What I think they might lack is a nomic character. Categories of nonscientific discourses can be legitimate and can pick out real objects even if those categories do not pick out things that are the subjects of natural laws. Dollars can be bills or coins, and there are no physical laws regarding dollars; yet I do not conclude that I am broke.^[4] I suspect that there are no laws regarding Toyotas, but I do not feel trepidation when I look out in the driveway every morning in fear that my car was an illusion. I suspect that there are no natural laws applying only to jigs, but I am not dissuaded from buying recordings of Irish music as a result. There are no physical laws regarding numbers, but that does not excuse me from balancing my check book properly or tallying my taxes. Nor do my doubts about natural laws governing dollars (or Toyotas or jigs) give me reason to accuse my employer (or my car dealer or the Bothy Band) of fraud. In general, the failure of a category to appear in a science does not cause me to doubt the reality of things to which that category is supposed to apply, or to doubt the legitimacy of the category. Indeed, the only cases in which I am inclined to make inferences in anything like this way are those in which an object-kind is introduced by hypothesis within the context of a scientific theory (e.g., phlogiston). I do, of course, doubt the existence of trolls and unicorns. But the reason I doubt them is that there seems to be no reliable evidence of their existence. It is not because there are no theories in which the kind "troll" or

"unicorn" plays a nomic role. If I were inclined to doubt trolls and unicorns on that basis, I would have to doubt dogs and Toyotas as well. In short, what you need to qualify a category for legitimacy in a scientific theory is something far stronger than what you need to qualify it for mere ontological legitimacy. Scientific kinds are reasonably orderly. Ontology is a motley.