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5 Broome’s account of reasoning Since Broome doesn’t think that satisfying the requirements of rationality is, as a matter of fact, always done by automatic processes, he does face the question how we comply with the requirements of rationality when we need to rely on some reasoning. How, on his view, can we reason our way to compliance with the Modus Ponens Requirement? As Broome says,3 his account is very similar to one that I had always been attracted to but that I had always felt nervous about because of its reliance on the notion of following a rule. Paul has favoured a rule-following account in the past, and he continues to favour it. However, he does now seem to have acquired some anxieties about it. I favour a rulefollowing account too, and it pleases me very much that Paul does, and that he continues to stick to it. But I don’t think he should have cold feet about it. I shall say why. So the disagreement we have here is an unusual one for philosophy: Not so much on the question which view is true, but on the question what temperature one’s feet should be at when putting it forward. I say your feet should be very cold; Broome says they can be quite toasty. What exactly is going on here? Let’s first look at Broome’s rule-based account of reasoning. Consider the simple inference: 1. (1) It’s raining. 2. (2) If it’s raining, the snow will melt. So, 1. (3) The snow will melt. Broome says: In reasoning, you operate on the contents of your premise-attitudes to construct the content of your conclusion-attitude. … Take the snow example again. You consciously believe that it is raining and that if it is raining the snow will melt. … You operate on these two propositions following the modus ponens rule [From ‘p’ and ‘if p, then q’ to derive ‘q’]. This rule tells you to construct the proposition that is the consequent of the second premise. You end up believing this consequent. … It is an essential feature of reasoning that the operation is rule-governed. In reasoning, you follow – are guided by – a rule. (pp. 231–2) Broome concludes by expressing satisfaction that he has arrived at an adequate account of reasoning. I have arrived at necessary and sufficient conditions for a process to be active reasoning. Active reasoning is a particular sort of process by which conscious premise–attitudes cause you to acquire a conclusion attitude. The process is that you operate on the contents of your premise-attitudes following a rule, to construct the conclusion, which is the content of a new attitude that you acquire in the process. Briefly: reasoning is a rule-governed operation on the contents of your conscious attitudes. (p. 234) As Broome says, this is a very appealing picture of reasoning. It seems to capture the sense in which we would like reasoning to be something we do, as opposed to merely being a causal process that takes place in our minds. It contrasts with what Broome calls the ‘jogging’ account of reasoning, according to which all that a thinker does is call to mind the contents of attitudes of hers; automatic processes then take over and she finds herself simply believing some new thing (the conclusion-attitude). Broome says that, by contrast, on his account “[reasoning] is an act.” (p. 235) As Broome notes, it would be harmless to say that some reasoning is correctly described by the jogging account. Many psychologists these days like to talk about what Daniel Kahneman (2011 ) calls System 1 reasoning—the sort of reasoning that is automatic, quick, sub-personal and done with little sense of voluntary control. A jogging model may adequately characterize such System 1 reasoning. But why are we so sure that not all reasoning can be captured by something along the lines of the jogging model?4 A reasonable first response is the one that Broome gives: It is simply obvious that there we are able to engage in reasoning in which we are active all the way from premises to conclusion. But I believe that there is a stronger point in the offing. Suppose some reasoning was such that, having rehearsed its premises, some conclusion simply came to you (accompanied perhaps by the feeling that it is ‘right’), but not accompanied by any awareness of the steps leading up to it. Full rationality would require that one ask oneself whether to endorse the conclusion that has simply come to you in this way. And this in turn would require that you lay bare the reasoning process by which the premises are supposed to have led to the conclusion. In other words, full rationality requires that a self-aware process of reasoning, one with no blind spots in it, vet the deliverances of an automatic process and rule on their correctness. It requires rational control. This gives voice, yet again, to the internalist picture of rational belief discussed in the last section. A further important point that can be made in favor of the rule-following picture of reasoning is that it enables us to capture something that seems very central to our reasoning abilities, and that is that they are both general and productive. 6 The rule-following proposal: the intentional view and the inference problem The challenge is to make sense of this rule-guided picture of reasoning. The problem I have in mind does not derive from a generalized skepticism about the idea of following a rule. That problem is associated with Wittgenstein and has been expounded most influentially by Kripke (1982 ). On Kripke’s well-known reading, there is a problem saying how it could be determinately true that we are following one rule as opposed to an infinity of other rules with which our finite behavior is also in conformity. What, asks Kripke’s Wittgenstein, would determinately make it the case that it is Modus Ponens that I am following, as opposed to some bent rule that deviates from Modus Ponens at some point past my computational abilities? (See Broome’s discussion of this on p. 241). Let me waive this problem for now (I’ll come back to it later). Let it be that there is as determinate a fact as you might want about which inference rule it is that someone has internalized or is following at this moment. The problem is to make sense of how such a rule could guide a person’s reasoning, in the way that Broome himself insists upon. You operate on these two propositions following the modus ponens rule. This rule tells you to construct the proposition that is the consequent of the second premise. You end up believing this consequent…It is an essential feature of reasoning that the operation is rulegoverned. In reasoning, you follow – are guided by – a rule. (pp. 231–2) When you look at this language, it is hard to resist the following picture of what’s going on. Somehow or other, you have come to accept the Modus Ponens (MP) rule. The rule says: From ‘p’ and ‘if p, then q’ to derive ‘q’. This rule forms the content of some intentional state of yours. When you recognize a pair of your attitudes to have contents of the MP form, you call this rule to mind. You see that it ‘tells’ you to derive ‘q’ from the premises and so you do so. You are guided by the rule to derive a new attitude from your previous attitudes. On this Intentional State construal of rule-following, then, your actively applying a rule consists in your grasping the rule, forming a view to the effect that its trigger conditions are satisfied, and drawing the conclusion that you must now perform the act required by its consequent. In other words, on this Intentional view of rule-following, rule-following is carried out with reasoning. You have to reason your way from what the rule tells you, plus your recognition that its trigger conditions are satisfied, to do what it calls for you to do. There is no doubt that some rule-following is like that. When I wake up my computer, I follow the rule: Tap any button, wait for the dialogue box to open, enter your password, then press ‘return.’ Of course, all this can happen very quickly because I may have automated the routine. But when something goes wrong it becomes very evident that all this rule-guidance by way of reasoning is there in the background and can be called to mind. But, if, as on Broome’s and my picture, rule-following is to explain reasoning, then this can’t be what rule-following in general consists in: it can’t both be the case that rule-guidance in general explains reasoning and that rule-guidance in general is explained by a process that involves reasoning from a rule. The two views can’t be true together. Elsewhere, I have called this the ‘Inference Problem’ for the notion of rule-guidance [see my (2008a , b, 2014 )]. 7 Rule-following without intentional states: dispositions So, if rule-guidance is to be the key to reasoning, we are going to have to find a way of thinking about how a rule might guide you in deriving a conclusion from some premises without this itself involving some reasoning. How is that to be done? We can try one of two tacks. The first and most radical would be to rid our picture of rule-guidance of any rule-encoding intentional state. The other would be to allow a rule-encoding intentional state into our picture, but to find a way of maintaining that it can exert its control over our thought and behavior in a way that’s non-inferential. Broome tries to convince us that the first idea can be made to work. In this respect, he follows in the footsteps of a number of philosophers who have thought that we can explicate what it is for a rule R to guide our thoughts merely in terms of our dispositions to conform to R under appropriate circumstances. On this view, roughly, for S to be guided by rule R is for S to be disposed to conform to R. If this sort of account could be made to work, then clearly there would be no Inference Problem. On my view, any such construal would not be an explication of rule-following, but rather an abandonment of it. There are at least four major reasons.5 First, rules prescribe what to do. They are sets of instructions that tell us what to do this or that thing under this or that circumstance. (Wakeup) If you want to wake up the computer, tap any button, then wait for dialogue box, then enter your password. Following them correctly means complying with their instructions. Necessarily, there is such a thing as following a rule correctly or incorrectly. Dispositions, however, don’t have correctness conditions. If a particular cube of sugar were not to dissolve in water, it wouldn’t be behaving incorrectly. It would just show that we had not yet figured out exactly which dispositions sugar has. Second, even if we could make sense of our dispositions having correctness conditions, the rules we follow have infinitary correctness conditions, whereas our dispositions are finite. Modus Ponens is defined for any three propositions that are related in a MP way, no matter how long or complex they may be. The rule that says, for any propositions that are related by MP while contemplated on the surface of the Earth, from ‘p’ and ‘if p, then q’ to derive ‘q’, is a completely different rule. You would not count as rational if you employed that rule. But how are we to make the distinction between full-blown MP and such bent rules, when we are restricted to making it on the basis of a person’s dispositions alone? Third, even with respect to the dispositions we do have, we know that they can contain dispositions to make mistakes. So, if we read off what rule we are following simply from our dispositions, we will attribute a rule that will be intuitively incorrect. Getting around this problem requires specifying in noncircular terms a set of optimality conditions under which it will be impossible for your dispositions to deviate from the rule that is, intuitively speaking, intended. But no one has succeeded in showing that there are such optimality conditions. Finally, following a rule involves being guided by it. But this element would appear to have gone completely missing from a Dispositional View. If the element of guidance were present, we would expect the disposition to conform to a rule to be explained by the agent’s acceptance of the rule. On a Dispositional View, that is impossible, however, since there is no rule-encoding state that explains the dispositions to behave, but only the dispositions themselves. 8 Broome’s dispositional account of rule-following Broome believes that the relevant objections to a Dispositional Account can be answered. However, Broome’s main innovation, which has some antecedents in the literature, is to add a certain sort of ‘seeming right’ to the exercise of the disposition that is said to constitute following a rule of reasoning. Modus Ponens’ guiding me on this occasion is: my being disposed to conform to MP, along with this behavior’s seeming right to me. Let us start by returning to the bizarre example and compare the two versions of it that I have by now described. In both, you start by believing it is raining and believing that if it is raining the snow will melt. In both versions, a causal process takes you from these beliefs to a new belief that you hear trumpets. In the original version on page 225, the new belief just comes to you. In the new version on page 233, you acquire the new belief by reasoning following a rule. The rule is incorrect, of course. It is the rule of deriving the proposition that you hear trumpets from the proposition that it is raining and the proposition that if it is raining the snow will melt. What is the difference between the two versions of the example? One difference is that in the version where you reason the process seems right to you, as I put it, whereas in the original version it does not. (p. 237) What is this notion of ‘seeming right’ such that it can, by its mere appearance, transform a purely causal process, in which one thought merely succeeds another, into a piece of reasoning, a process in which a rule of reasoning guides the thinker to actively derive a conclusion from his premise beliefs? Seeming right in our context is an attitude of yours towards the mental process you go through when you reason. An essential part of it is being open to the possibility of correction. When a process seems right to you, you are open to the possibility that the process might no longer seem right to you if a certain sort of event were to occur. We may call the event ‘checking.’ (p. 238) As Broome explains, this openness to correction is itself a disposition. You are disposed to lose the attitude of its seeming right in particular circumstances, specifically if checking occurs and produces a different result. By contrast, when you just find yourself believing you hear trumpets, there is nothing like this attitude. It is not open to correction in the same way, and there is no such thing as checking. Well, even when the belief about hearing trumpets just pops into your head, there is, of course, a lot of checking that you can do, since you can check whether you really do hear trumpets or whether it really is raining. Beliefs can always be checked. What Broome means, of course, is that in the one case, but not in the other, the process linking these beliefs will seem to you to be one that can be checked and corrected. And you are open both to checking it and to being corrected. However exactly this ‘seeming right’ is to be construed, there looks to be a puzzle about how to make sense of it. The crucial observation is that in the case of following a rule, or reasoning from some premises to a conclusion, what has to seem right is something relational: the behavior has to seem right relative to the rule that is being followed. What is at issue is not the correctness of a belief; it’s not even the validity of an inference. Rather, what is at issue is the correctness of the application of a particular rule. It could even be a bad rule, such as Affirming the Consequent. But if Affirming the Consequent is the rule you are following, then it ought to seem right to you to reason from ‘If p, then q’ and q to p. But now, how are we to make sense of the existence of this sort of relational seeming, while acknowledging that the subject doesn’t have access to an independent specification of what the rule is, given that we are working with a dispositional account according to which there is no rule-encoding intentional state. We may formulate this problem in the form of a dilemma: either Broome takes this seeming to be relative to the rule, or he does not. If he does, then he can drop the dispositionalism. An intentional state of the thinker’s that captures which rule the thinker ‘has in mind’ in performing a given inference will not need any help from the dispositional facts. It will solve the problems of correctness, although may still leave a puzzle about guidance (the Inference Problem). On the other hand, if the seeming right can’t be counted upon to have that rich relational content, but is effectively exhausted by the openness to correction, then Broome’s view is vulnerable to all the objections to the Dispositional View that we reviewed above. My own preference is to take the other tack, to allow a rule-encoding intentional state into our picture of reasoning, but to find a way of maintaining that it can guide our thought and behavior in a way that’s non-inferential. I take some small steps to explaining how this might work in (Boghossian 2012 , 2016 ).