A predicted diff erential ability to simulate odd mental states

Many simulationists have emphasized that our ability to simulate is linked to our ability to think about what we ourselves would do in hypothetical situa-tions.⁴ Th eir thought is that it is useful for us to be able to plan: to think about what we will do if such and such turns out to the case. A side eff ect of our ability to do this is that we can also predict how others will behave. We just think about what we would do if we were in their situation.

If this is right, it suggests that we might fi nd simulating some odd mental states easier than others. Our own mental states diff er in their vulnerability to revision. We regularly have to change many of our beliefs as we discover new and surprising things. Beliefs such as “Milton Keynes is a boring place to live”,

“My friend John likes me” and “Runner beans are easy to grow” are highly revis-able. I can imagine many scenarios in which I would be forced to change my mind on these matters. As such, I suggest, it is fairly easy to simulate someone who disagrees with me on such claims. In contrast, we rarely change our basic

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desires (that is, things that we desire for their own sake, such as food or sex).

Some people’s sexual interests revolve around rubber gloves or dead bodies, but I cannot imagine a scenario in which my sexual desires switched to such things, and have problems simulating such people. Along similar lines, certain “core beliefs” may be highly resistant to revision. I cannot imagine revising my belief that there are external objects, or that I am alive. Once again, trying to simulate someone without such beliefs seems diffi cult, if not impossible. Plausibly we can only simulate another if their mental states are ones that we ourselves might have had if the circumstances had been diff erent, or that at least is my sugges-tion. Now for some examples to make it seem plausible.

An easy simulation: a case with diff erent “peripheral” beliefs

Th e Maniac, fi rst published anonymously in 1909, seeks to provide an account of madness from “the maniac’s point of view”. During her spell of mania, the maniac suff ers from many delusions. At one point she comes out in severe acne (brought on, she thinks, by the medication she is being given), and starts to think that each spot is a “fat, white maggot, eating her alive” (Th elmar [1909]

1932: 188–9). It is, I suggest, quite easy to simulate someone who thinks that their spots contain maggots. Spots do look a bit maggoty, and we all know that there actually are some bugs that burrow inside the skin. It is easy to imagine situations in which we ourselves come to believe that there are insects inside us.

And, it is easy to imagine the kinds of thoughts that would follow from thinking oneself maggot-infested. One can imagine alternately scratching the spots to try to get the maggots out, and then being too repulsed to touch them, for example (indeed writing this my skin is crawling already).

I can imagine thinking myself maggot-infested and can simulate someone who thinks this. Similarly, it is comparatively easy to simulate the thoughts of someone who comes to believe that their friends all hate them, or that they can write brilliant poetry, for example. Here again, we can imagine many scenarios in which we ourselves might come to hold such beliefs.

A hard simulation: a case with diff erent basic desires

Th e title case of Robert Akeret’s Th e Man Who Loved a Polar Bear (1995) con-cerns Charles, a man who falls in love, in a sexual way, with a polar bear called Zero. Aft er his amorous advances lead to injury, Charles goes to consult Akeret.

At one stage Akeret goes with Charles to meet Zero. Looking at the bear, Akeret fi nds it hard to empathize with Charles. He writes: “At that moment I tried with all of my imagination to empathize with Charles, to feel what it would be like to love this bear as a man loves a woman. To lust aft er her. I confess that I could not do that” (1995: 82).

Simulating odd desires can clearly be harder than simulating odd peripheral beliefs. Th is being said, we can simulate at least some of those whose desires

diff er from our own. In some cases another’s desires can be seen as analogous to my own. So, suppose I do not fi nd my friend’s boyfriend at all attractive. Still I can simulate what her thoughts would be if she walked in to fi nd him in bed with another woman. I can imagine how I would feel in such a situation if it involved my partner and conclude that her feelings will be similar.

Still, I suggest, this process has limits. I do not think I can simulate how Charles would feel if he turned up at Zero’s cage to fi nd her snuggled up to a he-bear. On the one hand, if Charles is in love with Zero one can expect him to feel jealous. On the other hand, jealousy normally involves the thought that one could fi ll the place taken by another, whereas in the case of Zero and her bear-lover the reasons for Zero’s preferences would be fairly clear. All in all, I do not think I can simulate how Charles would feel in such a situation. I have no idea how his thoughts would go.

Maybe my problems with simulating Charles are merely down to a lack of imagination on my part, but at any rate, there seem to be clear-cut limits to the desires that we can simulate. Plausibly we cannot simulate desires in cases where we desire nothing analogous. So prior to becoming interested in sex, the idea of sex seems disgusting. Similarly, it is hard to simulate someone who feels compelled to tear their hair out if we lack such desires ourselves, for example.

An even harder simulation

Consider a patient who says the following:

I have not eaten for months / or gone to the toilet / all the organs within me have rotten / the food can’t pass through, everything has been coag-ulated / the Lonarid (paracetamol) that I took, have stuff ed my bowel, this is unfortunately my punishment / I am tired, I haven’t slept for years / I have no blood / I have no heart, it doesn’t beat anymore. I was deceived at the ECG department while they knew that my heart doesn’t beat anymore / you are deceiving me when you take my blood pressure, because I’m not alive anymore, I’m a dead-plant.

(Vaxevanis and Vidalis 2005: 42) Th is quote is from a patient suff ering from Cotard’s delusion. Importantly for the example, people with Cotard’s believe they are dead in the sense of non-being, rather than thinking that they have died and gone to heaven or hell. If we try to simulate the thoughts of such a person I suggest we just get stuck. I cannot think of any situation in which I would come to believe that I am dead.

Furthermore, if by chance I did come to believe I was dead, I do not know what other thoughts would follow. If you believe you are dead do you look for a doctor, or an undertaker? Suppose you go and see the undertaker and try to

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arrange your own funeral, how do you account for the fact that you can talk with the undertaker, walk around and get hungry?

Th e basic problem with trying to simulate such thoughts is that we cannot think of any circumstances in which we would come to share such thoughts our-selves. Along somewhat similar lines, in his discussion of Cotard’s delusion, John Campbell (2001) suggests that such patients may be incomprehensible to the rest of us because they hold diff erent “framework propositions”. In On Certainty (1969), Wittgenstein talks about the epistemic status of propositions such as “Th e world has existed for quite a long time” and “Th ere are a lot of objects in the world”. Unlike most propositions, such “framework propositions” are not open to doubt. Rather, other propositions are judged against them. As Campbell puts it: “it is only when we have the framework propositions in play, assumed to be correct, that it makes any sense to try to establish whether any proposition agrees with reality or not; we need the framework propositions in order to have any methods for testing at all” (2001: 96). Campbell’s suggestion is that patients with Cotard’s delusion take “I am dead” as a framework proposition. Th is is why the proposition is treated as something that is taken for granted and that is immune to revision. In Campbell’s account, it is because our framework propositions diff er from the patient’s that we cannot imagine thinking like them.

To sum up, it is plausible that we can only simulate another when we ourselves could come to have their thoughts, or at least thoughts analogous to their thoughts.

Simulating those whose peripheral beliefs diff er from our own is thus easier than simulating those with very diff erent basic desires or diff erent core beliefs.