My second argument for the (CRT) aims to establish that folk psychology contains obligation-imposing clauses like (OI) from Chapter 2. The guiding thought behind this argument is that while a proponent of the (CRT) agrees with the causal functionalist we’ve been considering on which mental states are possessed in all possible cases, perhaps there is disagreement between the two views on which mental states are possessed in certain impossible cases. Consider the following conditional.
(CP): If normative eliminativism were true, then there would be no beliefs.
By normative eliminativism, I mean the thesis that the world is just as it actually is in terms of the distribution of non-normative properties,87 but no normative properties are instantiated. Now, as a normative realist, I hold that normative properties are in fact instantiated in the actual world. Given the widely held thesis that normative properties metaphysically supervene on non-normative properties,88 my view entails that there are no metaphysically possible worlds at all where the antecedent of (CP) is true. Thus, (CP) is a counterpossible, a counterfactual whose antecedent is metaphysically impossible. My second argument for the truth of the (CRT) is that the (CRT) predicts correctly predicts that counterpossibles like (CP) will be true while alternative views incorrectly predict such counterpossibles will be false.
Before getting to the core of this argument, a few preliminary remarks about counterpossibles are in order. While I won’t be committing myself in this work to any specific proposal for analyzing counterpossibles, I am committed to rejecting the analysis counterpossibles are given on the standard Stalnaker-Lewis account of counterfactuals.89 On the standard account, a counterfactual is substantively true if its consequent is true at the closest world(s) where its antecedent is true, while it’s vacuously true if there are no worlds where its antecedent is true. The standard account thus entails that all counterpossibles are alike in being vacuously true.
Intuitively though, there seem to be important differences among counterpossibles. Naively, some seem truer than others. Compare (CP2) to (CP3).
(CP3): If as a child my uncle had succeeded in proving that there really is a greatest prime, green would’ve ceased being a color.
(CP2) and (CP3) are both counterpossibles since their (shared) antecedents are metaphysically impossible. There seems to be an important difference though. Naively, (P2) seems plausibly true in a way (P3) does not. In Counterfactuals, Lewis considers various ways of capturing intuitive differences of this sort among counterpossibles before finally settling on the idea of handling such differences in terms of assertability.90 To illustrate the proposal using the present case, Lewis’s thought would be that (CP2) is assertable in a way (CP3) is not even though they are both vacuously true.
Regardless of whether or not this is the proper way to handle this specific case, I must reject Lewis’s proposal as a general approach to counterpossibles. Given the metaphysical conclusions I eventually want to use (CP) to draw, it’s crucial to my argument that (CP) be substantively true. There are analyses available according to which at least some counterpossibles are substantively true, including analyses that don’t require a major revision of the standard approach to counterfactuals. For instance, on one analysis what we do is introduce certain impossible worlds into our ontology alongside possible ones, and then extend the standard analysis of counterfactuals in the obvious way. On this view, which Lewis briefly entertains, a counterpossible like (CP) will be substantively true if its consequent is true at the closest impossible world(s) that its antecedent is. I don’t mean to commit myself to this view; the point here is just that I’m going to need some such analysis of counterpossibles to be workable if my second argument for the (CRT) is even to get off the ground.
Now, it seems extremely plausible that if a counterpossible is going to be capable of expressing a substantive truth, its antecedent must be conceivable in some fairly robust sense.91 As an example of a counterpossible violating this requirement, consider (CP4).
(CP4): If some bachelors were married, interest rates would be slightly lower.
(CP4)’s antecedent is metaphysically impossible. More than this, though, it’s presumably analytic that no bachelors are married, and so (CP4)’s antecedent is inconceivable according to standard view of inconceivability.92 We have no genuine conception of what it would be for some bachelors to be married, and so we have no real grasp on how to make sense of claims about what would follow if they were. Thus, even if some counterpossibles express substantive truths or falsehoods, as my argument for the (CRT) requires, not all counterpossibles must do so, and (CP4) seems like an excellent candidate for one that doesn’t.
As I turn to make my argument for the truth of (CP), I will be assuming that (CP)’s antecedent is not inconceivable in the way (CP4)’s antecedent is. That is, I’ll be assuming that it’s not a contradiction in terms to suppose that non-normative properties were distributed just as they actually are while no normative properties were instantiated, in the way it is a contradiction in terms to suppose that some bachelors were married. This assumption strikes me as extremely plausible. It seems to me that it really is at least conceivable that, say, our scientific worldview might entail that there simply is no place for normativity within our best metaphysical theories – that (inter alia) it simply is not literally the case that subjects ought to do or believe anything..93
In assuming that (CP)’s antecedent is conceivable, I am in effect assuming that certain accounts of normativity are false. Specifically, I’m assuming the falsity of analytical reductionistversions of normative realism, according to which the totality of normative truths are analytically entailed by the totality of non-normative truths.94 According to analytical reductionists, normative eliminativism is a contradiction in terms in just the way married bachelors are. I will directly argue against analytical reductionism in Chapter 4, when I critically discuss various metaphysical accounts of normativity. In the present chapter, though, I just want to rely on the prima facie plausibility – the significant prima facie plausibility, in my view – of the thought that normative eliminativism is at least conceivable.
3.2.2 THE CRT ENTAILS THAT (CP) IS TRUE
Why appeal to counterpossibles in arguing for the truth of the (CRT)? The intuitive idea is that different theories of the essences of mental states take on different commitments about what must be the case if subjects are to be in mental states, with the central commitment of the (CRT) being that the subjects of mental states must possess certain normative properties. Conditionals like (CP) offer a natural way of trying to capture this commitment. Because normative realism, like many other metaphysical theses, is necessarily true if it’s true at all, such conditionals will almost inevitably be counterpossibles, as (CP) is. Thankfully, there’s no glaring reason to think that this counterpossible status is especially problematic for the purposes of capturing the (CRT)’s commitment to the claim that subjects of mental states must possess certain normative properties. Thus, it seems natural and correct to regard the (CRT) as being committed to the truth of (CP).
In contrast, it seems that views rejecting the (CRT) avoid this particular commitment. Again, consider the causal functionalist we’ve been imagining. Presumably, her view is committed to the claim that there must be causal relations if subjects are to be in mental states. If it were to turn out that, say, the fundamental laws of physics aren’t causal, and in turn that causation doesn’t somehow emerge as we rise above fundamental physics – in short, if it were to turn out that nothing literally causes anything – then on her view it would follow that subjects aren’t literally in mental states. However, this causal functionalist isn’t committed to the claim that subjects of mental states must possess normative properties. If non-normative properties were distributed just as they actually are, including the distribution of causal relations just as they actually are, then on this causal functionalist’s view nothing essential to belief would be missing. And so, it seems natural and correct to say that this causal functionalist, along with various other philosophers who reject the (CRT), require that (CP) be false.
Before moving on to address the question of whether (CP) is in fact true or false, let me conclude this subsection by noting that counterpossibles like (CP) seem like an extremely useful tool for thinking about the (CRT) even outside the context of the present argument. No matter how similar in various respects a given view might be to the (CRT) – think again of the causal functionalist we’ve been imagining, or of the constitutive-rationality-without-normativity view we examined in subsection 2.4.3 – if that view entails that mental states would be left in place even if the whole of normativity were somehow carved off the world, then that view must not really subscribe to the (CRT) as I’ve set it out. The test for whether a philosopher accepts the (CRT), then, is whether or not she accepts counterpossibles like (CP).
3.2.3 BELIEF ZOMBIES
The argument for the (CRT) from essential causal powers which I presented in the first section of this chapter gives us one reason to hold that (CP) is true, but here I want to provide an independent argument for (CP)’s truth, one that could potentially persuade those who weren’t persuaded by the first argument, and one that focuses on obligation-imposing clauses rather than obligation-satisfying ones. To set up the argument I want to make, let’s first consider an objection to (CP)’s alleged truth.
The most compelling objection I can think of goes as follows. If all non-normative properties were distributed in just the way they actually are while no normative properties were instantiated, then subjects would be in the very same physical and causal-functional states that we are here in the actual world. But then if (CP) were true, these conceivable physical and causal-functional duplicates of ourselves would have no beliefs at all. They would be belief zombies, analogous to the phenomenal zombies who come up in discussions of consciousness, but lacking belief states rather than phenomenal conscious states. Many philosophers of mind, including many physicalists, allow that phenomenal zombies are at least conceivable regardless of whether they think they are genuinely possible. But comparatively few philosophers of mind, and no physicalists that I know of, allow that belief zombies of the sort in question are conceivable.95 In fact, this is often viewed as one of the central differences between beliefs (along with other propositional attitude states) and phenomenal conscious states.
Why would one deny the conceivability of belief zombies? For broadly causal functionalistic reasons, most likely. Belief zombies would go through the very same sorts of physical motions we go through when performing intentional actions, they would produce the very same sounds and other physical marks we do when speaking and communicating, they would transition between their internal states in ways that are completely isomorphic to the various mental transitions we go through in thought.96 More generally, they would be in states possessing all the same causal powers that our mental states possess, including states possessing all the irrational, arational, and rational causal powers described above that belong to our beliefs.97 And as a topper, they would be completely physically indistinguishable from us. To many philosophers it seems inconceivable that beings like us in these various ways could fail to have beliefs.98 If these philosophers are right about this – and I think there’s at least a strong initial intuitive inclination to say that they are – then (CP) will be false. In short, then: the (CRT) requires that if normative eliminativism is conceivable, as we’ve been assuming that it is, then belief zombies are conceivable too. Thus, if it’s implausible that belief zombies are conceivable, then the (CRT) is implausible.
This strikes me as a very powerful argument for the falsity of (CP). I see no way to finesse the points it addresses. To defend the claim that (CP) is true then, and by extension to defend the (CRT) itself, I will need to argue that contrary to initial appearances, belief zombies are indeed conceivable. A defense of the conceivability of belief zombies will inevitably touch on issues closely connected to physicalism: if belief zombies are conceivable, how are we to block the (presumably antiphysicalistic) inference that they’re genuinely possible? We will get to these issues, but not until Chapter 5, where I discuss how the (CRT) bears on physicalism. For now, I want to limit my focus to establishing the conceivability of belief zombies.
As a way of softening us up for an eventual acceptance of the conceivability of belief zombies, I want to shift our focus temporarily away from belief to another mental state: knowledge. Consider the following analog to (CP).
(CP5): If normative eliminativism were true, there would be no knowledge.
I take something like (CP5) to be one of the central premises in Kim’s well known objection to Quine from his “What is ‘Naturalized Epistemology’?” paper.99
On Kim’s reading, Quine’s brand of naturalized epistemology is eliminativist about epistemic normativity.100 Given this eliminativism, Kim contends that Quine’s epistemology allows no place for the concept of justification, since justification seems to be clearly normative in nature.101 But, Kim continues, given the intimate link between justification and knowledge, any epistemology that doesn’t allow a place for the concept of justification won’t be able to allow a place for the concept of knowledge either. In fact, Kim claims, the intimate connection between justification and knowledge entails that the concept of knowledge itself is normative. Since a field of inquiry that has no place for the concept of knowledge cannot be properly classified as a form of epistemology, Kim concludes that Quine’s so-called naturalized epistemology isn’t really epistemology at all. It’s more like a branch of psychology.
I find this critique of Quine completely convincing. One natural way to cast the central part of Kim’s argument, it seems to me, is as follows.
(C): Quine’s naturalized epistemology entails that there is no knowledge.
However, if we accept Kim’s objection to Quine while continuing to suppose that normative eliminativism is at least conceivable, then we seem to commit ourselves to the conceivability of knowledge zombies, beings who are physical and causal-functional duplicates of ourselves but who completely lack knowledge. If (CP5) is true, as Kim’s argument requires (at least as I’ve cast it), while normative eliminativism is conceivable, as we’ve been assuming, then knowledge zombies must be conceivable too.
Contraposing this conditional: the only ways to block the conclusion that knowledge zombies are conceivable are either to reject Kim’s critique of Quine or to deny the conceivability of normative eliminativism. This latter move would presumably involve embracing analytical reductionism and holding that the totality of normative truths is analytically entailed by the totality of non-normative truths. Each of these moves strikes me as deeply objectionable, and so I think we should embrace the conceivability of knowledge zombies.
3.2.5 THE SPACE OF REASONS
Now that we can see why one would think that knowledge zombies are conceivable, let’s shift our focus back to belief.102 Reconsider (OI), the obligation-imposing normative clause which was first introduced in Chapter 2.
(OI): If a subject’s total evidence supports P, then that subject ought to believe that P.
If normative eliminativism were true then it wouldn’t be the case that subjects ought to do anything, and so (OI) would be false. But then, I claim, something essential about belief would be missing. Just as knowledge is tied to justification in such a way that you can’t have the former without the latter, belief is tied to rational obligations of the sort expressed by (OI) in such a way that you can’t have belief without such obligations.
To maintain a sort of symmetry with obligation-satisfying clauses, I’ve phrased the obligation-imposing clause (OI) using the normative ‘ought.’ To give my present claims more resonance with the views of other philosophers, though, it might help to translate (OI)’s ought-talk into reasons-talk.103
(OI*): If a subject’s total evidence supports P, then that subject has an (overall) reason to believe that P.
(OI*) is meant to express at least roughly the same proposition that (OI) does. Having a reason, just like being such that one ought to do something, is an uncontroversially normative property, and so (OI*) counts as a normative clause.
If normative eliminativism were true then subjects wouldn’t have reasons to believe that which their total evidence supports, and so (OI*) would be false. More generally, if normative eliminativism were true then subjects would never have any reasons to believe anything, and subjects’ beliefs would never provide them with any reasons for action or further belief. The causal functionalist we’ve been considering, along with all other philosophers who would deny (CP), seem to be committed to the view that belief’s relation to this “space of reasons” is not truly essential to it, at least in the sense that there could be beliefs even if there were no reasons. This view of the relation between beliefs and reasons strikes me as deeply unattractive, and perhaps even incoherent. I find far more compelling the view that part of the essence of belief is to be bound up with reasons in such a way that it makes no sense to speak of beliefs in the complete absence of reasons,104 just as it makes no sense to speak of knowledge in the complete absence of justification. Carve the space of reasons off the world and you carve belief off as well. Because this seems right to me, I accept (CP): if normative eliminativism were true, and thus there were no reasons, there would be no beliefs.
Those who would deny the conceivability of belief zombies face a dilemma. They can deny the conceivability of normative eliminativism – again, presumably by embracing analytical reductionism. Or they can sever the connection between beliefs and reasons, deny that it’s truly part of belief essence to stand in any relation to a space of reasons. There doesn’t appear to be a third option. Each of the two available moves strikes me as extremely unattractive, and so I embrace the conceivability of belief zombies. Their apparent inconceivability is, on my view, superficial. On first thought, it does indeed seem that the physical and causal-functional duplicates of us in question would have everything it takes to be believers. On second thought, though, we appreciate that these duplicates inhabit a place – an impossible, but conceivable place – where there are no reasons. And a place without reasons is, ipso facto, a place without beliefs.
This completes my second argument for the truth of the (CRT). In this argument I’ve tried to show that the (CRT) predicts that the counterpossible (CP) will be (substantively) true while alternative theories of the essences of mental states predict that (CP) will be false. I’ve then tried to establish that given the intimate connection there is between beliefs and reasons, it’s highly plausible that (CP) is true, even though this entails the conceivability of belief zombies. Since the (CRT) correctly predicts (CP)’s truth while its competitors incorrectly predict (CP)’s falsity, I thus conclude that we should infer that the (CRT) is true.