the old opposition between theorizing and simulating? It seems to evaporate.
True, I still insist on the possibilities of cooperation and independence, in which theorizing and simulating retain their distinctive identities. I am not declaring that simulation ‘‘reduces’’ to theorizing or vice versa. But the mod-erate rapprochement between theorizing and simulating that I admit as a possibility seems to blur the old contrast, and that seems unsettling. What are the new terms of debate?
A helpful way to frame the new debate is in terms of ST versus simulation-neglecting TT. Under these terms of debate, it’s no longer enough for TT to show that theorizing somehow takes place in mindreading; it must also show that this theorizing isn’t merely an implementation of simulation.19Orthodox TT has usually denied or minimized the role of simulation. So it seems fair to reconstruct the debate so that TT has the burden of making good on its neglect of simulation. TT must show that theorizing isn’t merely scaffold-ing for simulational processes. By the same token, proponents of ST (or a simulation-centered hybrid) can no longer earn victory over TT simply by showing that theorizing is not the standard method of mindreading. To gain victory over its rivals, ST must establish the intensive use of simulation as defined by the positive characteristics we have described. The major change in our new delineation of ST is that its defenders are no longer required to demonstrate the absence of theorizing. Demonstrating such an absence has long been regarded as a core burden of ST (avoiding ‘‘collapse’’ into TT).
This is an obscure task, given the opacity of the notion of ‘‘tacit’’ theory. The new terms of the debate free ST from this old, misplaced burden.
If the test of ST is a positive one, however, more must be said about the positive characteristics of simulational mindreading. One point in need of clarification is the connection between our resemblance definition of simulation and the standard ST story about mental pretense, highlighted in figure 2.3. So I end this chapter with an explanation of what I mean by mental pretense and how it fits with the resemblance, or duplication, account of simulation.
representations into one’s possible world box. Although the possible world box is analogous to their belief box, they say that the functional role of representa-tions in the possible world box is quite different from the functional role of either beliefs or desires. This confirms the impression that mental pretense is under-stood as a distinct type of propositional attitude.
This approach does not suit ST. If pretense is a distinct attitude, how can we intelligibly talk about pretend-belief, pretend-desire, pretend-hope, and so forth, as simulationists are wont to do? If pretense is a separate attitude, each hyphenated phrase would designate a compound attitude, and it’s unclear what such a compound would be.
A second way to conceptualize mental pretense is to conceptualize it, in the first instance, as an operation or process. The outputs of the process can be called pretend states. This is my preferred way to conceptualize mental pretense. Moreover, I want to identify the operation of mental pretense with a species of imagination. Imagination is an operation or process that scientific psychology should take seriously, something to which it should be ontolog-ically committed. However, there are different possible approaches to imag-ination and perhaps different types of imagimag-ination.21
In ordinary language, the verb imagine sometimes takes a that-clause com-plement, and in this construction, imagining that p is roughly equivalent to supposing that p. If I imagine that the United States lacked the atomic bomb in 1945, what I do is suppose, assume, or hypothesize that the United States lacked the bomb in 1945. Exclusive focus on this construction might lead to the view that imagination is always supposition. The trouble with this, as a full account of imagination, is that imagining sometimes generates different mental products.
Imagining can create imagery of various kinds, as when one imagines seeing certain sights or hearing certain tunes run through one’s head. Notice that in these uses, there is a different syntactic construction: ‘‘imagine M-ing’’ or
‘‘imagine feeling M,’’ where M can designate any of a number of mental states, not just suppositions. For example, I can imagine seeing a yellow parrot, feeling sad, feeling outraged, or feeling elated. It is also possible, no doubt, to imagine that one feels elated, which is equivalent to assuming the truth of the proposition
‘‘I am elated.’’ But there is another way to imagine feeling elated, namely, to conjure up a state that feels, phenomenologically, rather like a trace or tincture of elation. Our ability to do this is not confined to sensations, perceptions, or emotions. One can also imagine having attitudes such as desire, hope, doubt, and ambivalence. The range of states that can be imagined suggests that imagining, in a more inclusive sense, is an operation or process capable of creating a wide variety of mental states. Imagination’s output, so understood, is not a single type of state but any one of a number of mental-state types, most of which are not suppositions. When I imagine feeling elated, I do not merely suppose that I am elated; rather, I enact, or try to enact, elation itself. Thus, we might call this type of imagination ‘‘enactment imagination.’’
Another mental verb that displays a similar range of interpretations and grammatical complements is remember. A person can remember that she was drunk, that she felt elated, or that she saw a tortoise cross the road. But she can also remember being drunk, feeling elated, or seeing a tortoise cross the road. These syntactic constructions for describing memory correspond roughly to what psychologists call ‘‘semantic’’ memory and ‘‘episodic’’ mem-ory. It is debatable whether episodic memory requires reenactment of a re-membered episode. But, I submit, imagining being in M does require at least partial enactment, or attempted enactment, of being in M.
I propose that pretend states—in the sense intended by ST—are states produced by enactment imagination (E-imagination). A pretend desire is the product of enacting, or attempting to enact, desire; a pretend state of fear is the product of enacting, or attempting to enact, fear; and so on. Pretend desire is quasi desire produced by E-imagination, pretend fear is quasi fear produced by E-imagination, and so forth. All of these proposals have at least some intuitive appeal, but I do not rest my proposals on intuitive considerations. In chapter 7, we’ll explore empirical evidence to see whether this entire idea of construing imagination and pretense in enactment terms is viable.
What’s the connection between imagination in the suppositional sense (S-imagination) and E-imagination? One possibility is that S-imagination is a species of E-imagination. Supposing that p may be equivalent to E-imagining believing that p. In other words, a supposition might be a pretend-belief, where this is understood in the enactment sense of pretense or imagination. An al-ternative possibility is that S-imagination is a sui generis form of imagination, irreducible to E-imagination. I am attracted by the reductive proposal but won’t insist on it.22
We speak colloquially of ‘‘make believe.’’ To make believe that p is to make oneself have a certain belief or belieflike state. Analogously, there are states of ‘‘make desire,’’ ‘‘make hope,’’ and so on. A process-product dis-tinction is appropriate here. In the process sense, ‘‘making’’ believe is the activity of endogenously producing token states that resemble beliefs, that is, states that are normally produced in an exogenous, nonpretend fashion. In the product sense, make-believe is a state produced in this endogenous or top-down fashion. What simulationists call ‘‘pretend states’’ are states like make-believe, make-desire, and so forth. They are states produced by an operation of mental pretense, or E-imagination.
Of course, pretend states constructed for mindreading purposes may not match the intended states of the target even approximately because they may have been chosen badly out of ignorance. But what kinds of matching, or resemblance, are pretend states capable of, in the best of conditions—when the propositional content is aptly chosen? How closely can a pretend-desire for p resemble a genuine, nonpretend desire that p? Moreover, what are the pertinent respects of resemblance?
At least three categories of resemblance are eligible: introspectible, func-tional, and neural respects of resemblance. For some categories of imagina-tion-created states, especially visual and auditory imagery, there seem to be substantial introspectible points of resemblance. For other categories of pre-tend states, introspectible resemblances are more problematic. Can one tell introspectively how similar a state of pretending-to-hope-that-p is to a genuine hope-that-p? In any event, cognitive scientists will place little credence in introspectible resemblances. These are not measurable facts. Another reason to place minimal weight on introspectible respects of resemblance is that their comparative paucity probably understates the overall resemblance between states. Pairs of states quite similar in functional and/or neurological respects may be quite different in terms of introspective accessibility. Many illustra-tions of this will be encountered in chapters 6 and 7.
When we turn to the functional and neural categories, promising dimen-sions of resemblance are revealed by empirical research. A pretend desire with a given content might share important functional properties with a non-pretend desire of the same content, and ‘‘endogenously’’ generated fear might share important neural properties with normal, ‘‘exogenously’’ generated fear.
Initially, the prospect of functional and neurological similarities may seem dim. Surprising as it may sound, though, research supports such theses. These are the kinds of similarities I consider most relevant to ST.
ST orthodoxy assigns a pivotal role to the creation and deployment of pretend states. Given their prominence in the present treatment, including the diagrammatic presentation in figure 2.3, the reader might assume that pretense and pretend states are essential parts of my ST story as well. This is not so. Pretense and pretend states are one possible realization of the resemblance-related features crucial to simulation, but not the only possible realization. The constructs of imagination and pretense have connotations associated with higher (and more ‘‘central’’) cognitive activity than some of the activities we’ll be dealing with here. As chapter 6 will indicate, recent cognitive science and cognitive neuroscience disclose striking instances of mental simulation that are largely automatic and unconscious. These cases are ones to which terms like imagine, imagination, pretend, and pretense do not naturally apply. These cases are probably underpinned by a very dif-ferent neurocognitive architecture. By disengaging our account of simula-tion from pretense or imaginasimula-tion, we leave room for this important class of cases. At the same time, cases that comfortably fit under the rubrics of pretense and imagination can also fit under the heading of simulation, given our resemblance explication of that notion. Thus, our treatment of low-level simulational mindreading in chapter 6 makes no reference to E-imagination or pretense, whereas the treatment of high-level simulational mindreading in chapter 7 makes extensive reference to E-imagination and pretend states.
This completes my conceptual overview of the mentalizing controversy, as well as my articulation of the theoretical construct of simulation. The foun-dation is now laid for the empirical evidence of simulation to be assembled in chapters 6, 7, and 8. We shall show, first, that mental simulation, both in-trapersonal and interpersonal, is a robust phenomenon of the human mind.
This includes interpersonal mental mirroring, or resonance (chapter 6), as well as visual and motor imagery (chapter 7). Second, a wide range of evi-dence will be presented that supports the thesis that mental simulation is intensively used for mindreading. Well-replicated findings, such as deficits in face-based emotion recognition (chapter 6) and rampant egocentrism (chap-ter 7), are most naturally and plausibly explained by simulational methods of attribution. Before turning to this evidence, however, we use the next three chapters to pinpoint problems with ST’s principal rivals: rationality theory, child-scientist theory, and modularity theory. Readers mainly interested in ST could proceed directly to chapter 6.
Notes
1. As we shall see, however, it isn’t necessary for ST to deny that theoretical inference plays some kind of role in mentalizing; it might even implement a simu-lation routine.
2. As we shall see in chapter 4, there is at least one proponent of TT, namely, Andrew Meltzoff, who subscribes to this variant. In general, however, special first-person knowledge is anathema to psychologist proponents of TT.
3. Thus, in chapter 5, Alan Leslie’s view is classified as a specimen of TT because he maintains a theoretical-inference view of third-person attribution, though he rejects a functionalist, or conceptual-role, account of mental-state concepts. As a somewhat distinct matter, notice the importance of distinguishing between functionalism as a theory of folk mental-state concepts and functionalism as a factual, or metaphysical, matter (psychofunctionalism). It is one thing to say that tokens of mental-state types in fact have patterns of causal interaction with external stimuli, peripheral behavior, and other mental-state tokens or even to say that tokens of mental-state types are (meta-physically) constituted by such interactions. Either of these theses is a far cry from the thesis that the folk naı¨vely represent, or conceptualize, mental-state types in terms of such causal interaction patterns. The question of contents for mental-state concepts concerns only the latter issue, the ‘‘conceptualization’’ issue, not the factual or meta-physical issue.
4. An alternative, modular approach to TT might say that the psychological law does not get deployed in the form of a premise belief that is inputted into the infer-ential process. Rather, a module specialized for decision prediction incorporates such a law in its inferential architecture and processes belief and desire inputs in accor-dance with it. Although this approach is possible, I know of nobody who has explicitly embraced it, so it will be ignored in future discussion.
5. A modular form of TT would hold that the reasoning is executed by a dedicated theory-of-mind module rather than by a general-purpose reasoning mechanism.
However, a factual reasoning mechanism would still do the essential work. That much is common to all forms of TT and stands in contrast with the (pure) ST approach.
6. The term routine is used here and throughout in a loose and nontechnical sense.
7. Thanks to Kelby Mason for this point.
8. I refer here to a finding of Mitchell, Banaji, and Macrae (2005), to be discussed in section 7.5. In addition, one prominent theory-theorist, Andrew Meltzoff, has fre-quently proposed that infants make ‘‘like me’’ (mental) inferences based on imitation (see section 4.8).
9. There is a close parallel here with the classicism-connectionism debate in cog-nitive science. Classicists often point out that classical computation might be im-plemented by connectionist networks, yet this is perfectly compatible with the truth of classicism, properly understood.
10. To increase confusion, there is a third sense of simulation positioned halfway between the computational modeling sense and the replication sense intended here. In cognitive science, the phrase mental simulation is sometimes used for the kind of cognitive activity posited by the mental models approach (Craik, 1943; Johnson-Laird, 1983; Johnson-Laird and Byrne, 1991; Hegarty, 2004). According to this approach, the mind constructs small-scale models of reality that are used (in working memory) to represent and reason about the world. Mental models are often said to be ‘‘iso-morphic’’ to the physical situations they represent or to exhibit ‘‘analog’’ properties.
This appears to combine the replication or resemblance theme with the modeling theme and is therefore easily confused with either the computational modeling sense, on the one hand, or the replication sense, on the other. A point to be emphasized is that when I speak of ‘‘mental simulation,’’ I shall mean a replication or duplication of another mental state. A mental simulation is a simulation of a mental state by a mental state. By contrast, the mental models approach regards mental simulations as simu-lations of, and hence isomorphic to, external or physical states of affairs. This ap-plication is one I reject, or have strong doubts about, at least if ‘‘isomorphism’’ implies any simple, commonsense form of resemblance.
11. It is probably inappropriate to regard a token process P as having the function of duplicating a particular process P¢. A more careful formulation would say that the token process P is of a type whose function is to duplicate another type (of which P¢ is a token).
12. Perhaps a better label would be ‘‘mental-mental’’ simulation, as suggested by Justin Fisher. But I’ll stick with the shorter form.
13. The exact spatiotemporal contours of seeing the ocean are a delicate matter.
Some might want to include in this process the light waves that travel from the ocean to the perceiver’s retinas. For present purposes, however, the only relevant part of seeing is the part that takes place in the perceiver’s mind. In this context, that is the intended referent of the term seeing.
14. The term successful is not intended here to imply purposefulness or in-tentionality. I don’t wish to claim that all simulation is purposeful. In calling a sim-ulation successful, I merely mean that it involves genuine duplication, at least approximate duplication, whether intended or unintended.
15. Without mentioning this body of experimental evidence, Nichols and Stich (2003) also observe that people tend to impute their own beliefs to others. They accordingly posit a special method of mindreading they call ‘‘default belief attribu-tion.’’
16. Jeannerod and Pacherie (2004) also list explicitness as a dimension of vari-ability. I don’t follow suit here because I don’t regard explicitness or implicitness (consciousness or nonconsciousness) as a dimension of strength. An implicit simu-lational process is still fully simusimu-lational. The mindreading processes discussed in chapter 6 are almost all thoroughly implicit, but this doesn’t make them weaker instances of simulation than explicit examples.
17. Thanks to Robert M. Harnish (personal communication) for suggesting that simulation involves a control process, as well as embedded processes of other kinds.
18. Facial expression of emotion is a possible exception, to be explored in chapter 6.
19. This new framing of the TT-ST debate—in which theory-theorists must show that theorizing isn’t merely an implementation of simulation—nicely resembles the standard framing of the dispute between classicist and (radical) connectionist views of cognitive architecture. Thanks here to Philip Robbins.
20. Mental pretense stands in contrast to behavioral pretense. It does not involve any outward behavior, just mental states. Pretend play, being a behavioral matter, is not included under the heading of mental pretense, though mental pretense would, presumably, be the internal guide to outward pretend play.
21. Currie and Ravenscroft (2002) have independently developed a similar treat-ment of imagination and treat-mental pretense.
22. For further discussion, see chapter 7.