Rationality as reasons-responsiveness Benjamin Kiesewetter, Humboldt-Universität zu Berlin Forthcoming in: Australasian Philosophical Review Abstract: John Broome argues that rationality cannot consist in reasons-responsiveness since rationality supervenes on the mind, while reasons-responsiveness does not supervene on the mind. I here defend this conception of rationality by way of defending the assumption that reasons-responsiveness supervenes on the mind. Given the many advantages of an analysis of rationality in terms of reasons-responsiveness, and in light of independent considerations in favour of the view that reasons-responsiveness supervenes on the mind, we should take seriously the backup view, a hypothesis that explains why reasons-responsiveness supervenes on the mind even though paradigmatic reasons are external facts. I argue that Broome's objections to the backup view, as well as his more general objection to the thesis that reasonsresponsiveness supervenes on the mind, do not succeed. I The idea that rationality and normativity are essentially related to each other has a long tradition in the history of philosophy. It is present in Plato's conception of the rational part of the soul as directing us towards the good, in Aristotle's view that being virtuous involves following prescriptions of rationality, as well as in Kant's conviction that we gain insight into the moral law and can be motivated to act accordingly by way of exercising our capacity of practical reason. In the 20th and 21st century, when the notion of a reason became increasingly important for the conception of normativity, the idea is present in the common assumption that rationality is a matter of responding to reasons, or put the other way around, that reasons are the kind of things that can make responses rational – an assumption that can be found in the influential works of Donald Davidson, Philippa Foot, Christine Korsgaard, Derek Parfit, Joseph Raz, and Bernard Williams, among others. Some authors might have adopted this assumption as part of a stipulative definition of 'rationality'. But it is natural to think that at least in most cases, the philosophers who made this assumption were concerned with a notion that is rooted in ordinary uses of the term 'rational' rather than a purely stipulated one. 2 In his article "Rationality versus normativity", John Broome argues that the many philosophers who held this view "fail to respect the distinction between rationality and normativity" (Broome forthcoming, 1). That rationality is a matter of responding to reasons, or that reasons are the kind of things that make responses rational, suggests that the property of being rational and the property of being reasons-responsive are co-extensional. Broome argues, however, that these properties cannot be co-extensional, since the property of rationality is a mental property, or at least a property that supervenes on the mental, while the property of being reasons-responsive depends (at least in part) on the world outside of our minds. For this reason, the link between reasons and rationality that so many philosophers have taken for granted must be rejected. Rationality is one thing, normativity quite another one; a statement about an agent's reasons "does not impugn the agent's rationality at all" (ibid.). One might wonder: Where did those who assumed that rationality and reasons are linked in the way suggested go wrong? Although Broome is not explicit about this, his historical sketch of the meanings of 'reason' and 'rationality' suggests that they have been misled by an ambiguity of the term 'reason'. According to Broome, 'reason' has an explanatory, a normative, and a mental meaning. In its mental sense, 'reason' refers to a mental faculty; this sense needs to be distinguished both from the explanatory sense of 'reason' as well as from the normative sense, in which a reason is something that counts in favour of, or requires, certain responses. The more recent term 'rationality' has long been synonymous with 'reason' in the mental sense, before it came to refer, in addition, to the property of being in a state of mind that could have arisen from an exercise of the rational faculty and other properties related to that faculty (cf. Broome forthcoming, 4). As far as this story goes, the connection between rationality and reasons in the normative sense amounts to no more than the fact that 'rationality' is semantically related to a mental faculty which we also refer to using the term 'reason' – the same term that we use to refer to something entirely different, namely normative reasons. But surely, the philosophers I mentioned as proponents of the view that rationality is a matter of responding to reasons did not fail to distinguish between the capacity of 'reason' and 'reason' in the sense of a favourer. More plausibly, they thought that there was an essential connection between these two notions. As Broome sees things, Hume's claim that 3 "'tis not contrary to reason to prefer the destruction of the whole world to the scratching of my finger"1 horrified many philosophers only because they were confusing the mental with the normative sense of 'reason'. More charitably, however, they assumed that the capacity of reason is the capacity to respond to normative reasons. If it's not contrary to reason to have a preference for the destruction of the world, then we could successfully exercise the faculty of reason and hold onto such a preference. But if the faculty of reason is the capacity to respond to reasons, it seems to follow that there is no reason, or at least no significant one, against having such a preference. The idea that the faculty of reason or rationality is or involves the capacity to respond to reasons is, I think, a natural and attractive one. To begin with, it could explain why (although it does not entail that) only rational beings, beings endowed with the capacity of rationality or reason, are subject to normative requirements, and it would vindicate our being subject to normative requirements, conditional on the plausible idea that we can be subject to normative requirements only if we are capable of detecting and responding to them. Secondly, it opens up the possibility of an intuitive and informative reductive account of the property of rationality as the normative property of being responsive to reasons, i.e. of being such that one F-s whenever one's reasons require one to F.2 Such an account in turn provides an illuminating explanation of what it means to say that rationality makes prescriptions, that being irrational involves violating such a prescription, and that ascriptions of irrationality amount to a serious form of criticism. By the same token, it delivers a straightforward vindication of the idea that rationality is a property that we have reason to care about. Indeed, as I have argued elsewhere, it would provide a particularly attractive solution to the why-berational challenge (Kolodny 2005), because it entails that rational requirements are necessarily accompanied by normative reasons without having to appeal to a special reason to follow such requirements – a reason that has been proven very difficult to find for Broome and many others.3 Finally, that rationality is a normative property makes sense of the fact that the study of rationality is a subject of the discipline of philosophy rather than, for example, psychology. 1 Hume (1739, 416). 2 Cf. Kiesewetter (2017, Ch. 7); Lord (2018). It is plausible to think that the relevant notion of reasonsresponsiveness is more complex than the one discussed here and by Broome, but this doesn't affect the present dialectic. See Lord (2018) for a more ambitious conception. 3 Cf. Broome (2007); Kiesewetter (2017). 4 On Broome's view, by contrast, the capacity of reason is related to reasons in the normative sense in about as much as a river bank is related to the financial institution called 'bank'. Accordingly, any presumed connection between having the capacity of reason and being subject to reasons would appear to be coincidental at best: we wouldn't have more reason to expect such a connection than to expect to find a cash machine on a river bank. Moreover, Broome offers no informative account of the property of rationality, nor does he provide much general information about this property, other than that it is a property that we have when we satisfy the requirements of rationality and lack when we don't satisfy them. But again, Broome doesn't tell us what it means to say that rationality "requires" something of us; he only appeals to an analogy with legal and moral requirements. Yet legal requirements can plausibly understood in terms of conventional rules of a particular kind, and moral requirements can plausibly be understood as normative requirements (i.e. requirements of reasons of a certain sort). Since rational requirements are not contingent like conventional rules, and since they are not, according to Broome, requirements of reasons, neither analogy helps, and it remains obscure what rational requirements are supposed to be in his picture. Further, if rationality is not a normative but a mental property, as Broome claims, it is unclear why the charge of irrationality is a form of criticism, and what is wrong with being indifferent about whether one is rational or irrational. To vindicate these claims, which seem part of our ordinary understanding of rationality, one would need to put forward a reason that necessarily favours having that particular mental property. But as Broome has argued himself, the assumption that there is such a reason is difficult to justify. Others have argued that there cannot possibly be such a reason.4 So there is much to like about the idea that rationality consists in reasonsresponsiveness. But there are also important challenges to it. Broome presents a particularly forceful objection: The property of rationality supervenes on the mind. That is, if A and B share all mental properties, then A is rational if and only if B is rational. The property of reasonsresponsiveness, in contrast, does not appear to supervene on the mind, at least as long as we hold on to the assumption, which seems part of our ordinary understanding of reasons, that external facts can be reasons. For if external facts can be reasons, then A and B might share 4 See Kolodny (2005); Kiesewetter (2017, Chs. 4-5). 5 all mental properties while having different reasons and thus differing with respect to their reasons-responsiveness – or so it seems plausible to think, at least prima facie. I agree with Broome that rationality supervenes on the mind, and I agree with him that external facts can be reasons.5 And yet I think that an analysis of rationality as reasonsresponsiveness can be defended. I will defend this analysis by way of defending the view that even though what reasons we have does not supervene on the mind (as external reasons can be facts), reasons-responsiveness supervenes on the mind because what our reasons require of us supervenes on the mind. The attraction of this view (which I have elsewhere called "the backup view") is that it allows us to preserve all three of the following assumptions: that rationality supervenes on the mind, that rationality is a matter of responding to reasons, and that external facts can be reasons. Before turning to the backup view, however, I will start by presenting an independent argument for the thesis that reasons-responsiveness supervenes on the mind (Sec. II). Subsequently, I will address Broome's objection to this thesis, including his objections to the backup view (Secs. III-V). II One good reason to consider the view that reasons-responsiveness supervenes on the mind as a serious theoretical option is provided by the inherent attractiveness of the view that rationality consists in reasons-responsiveness itself. But it's worth noting that the view can also be independently motivated. As I shall argue now, it enables us to solve an important problem that is raised by three-option cases, such as Jackson's Drug Example (Jackson 1991) or Parfit's Mine Shafts (Parfit 2011). Consider a very simple theory according to which reasons-responsiveness does not supervene on the mind. According to this theory, there are only two reasons, each of which is a reason against an action. The first is a relatively weak reason provided by the fact that the action in question involves breaking a promise; the second and stronger reason is provided by the fact that the action in question involves killing an innocent. Suppose you have three options: option (i) involves killing an innocent (in a way that does not involve breaking a 5 Throughout this paper, I assume an internalist conception of the mind. 6 promise); option (ii) involves breaking a promise (in a way that does not involve killing an innocent); and option (iii) involves neither killing nor promise-breaking. The theory then entails that your reasons require you to take option (iii) and to refrain from options (i) and (ii).6 But given what the theory says about the weights of the relevant reasons, it also entails that (ii) is more strongly supported – or, as I will put it, that (ii) has a higher degree of reasonsresponsiveness – than (i). Supposing (for illustrative purposes) that the reason against killing is ten times stronger than the reason against breaking a promise, we might represent the degree of reasons-responsiveness of each option with the following numbers: (i) -10; (ii) -1; (iii) 0. Next, consider the following scenario. You know that you have promised someone to do either A or B. You also know that either doing A or doing B involves killing an innocent, but you don't know which. Moreover, you know that there is a further option C available, and that taking this option would involve breaking your promise but also making sure that you don't kill an innocent. In this case, the theory entails that your reasons require you to refrain from option C. We have seen this already, as option C is equivalent to option (ii). At the same time, however, we can say that relative to your mental state, C has the highest expected reasonsresponsiveness, where the expected reasons-responsiveness of an option is the weighted average of its possible degrees of reasons-responsiveness. Supposing that relative to your mental state, the assumption that A involves killing an innocent and the assumption that B involves killing an innocent each have a probability of .5, C's expected reasons-responsiveness is -1, while the expected reasons-responsiveness of each of the other options is -5. Hence, the theory entails that your reasons require you to refrain from the option with the highest expected reasons-responsiveness. This implication creates problems for our theory. The first problem is that option C is the only option that you can responsibly take, and that it is counterintuitive to say that reasons require us to refrain from the only option that we can responsibly take without imposing an unacceptable risk to some innocent person's life. Call this the objection from recklessness. The 6 This follows from the assumption that reasons require one to take an option if it is the only one in which one does not flout a reason. It also follows from the assumption that reasons require one to take an option if the balance of reasons favours that option. One might question these assumption on grounds of what are sometimes called "enticing reasons" (cf. Dancy 2004), but we can stipulate that the reasons in question are not merely enticing. 7 second problem is that in the case described, the theory entails that you are in the position to know that the only responsible option is one that you ought not to take. Now, if anything like Broome's enkratic principle is on the right track, then it's irrational to intend to take an option that one believes one ought not to take. So the theory entails that if you find yourself in a scenario like the one described, you cannot rationally make a responsible decision as long as you believe the true theory about reasons. But surely believing the true theory about reasons must be compatible with rationally making responsible decisions under uncertainty. And so we have a reductio of the theory. Call this the objection from enkrasia.7 Needless to say, the theory I have chosen as a model needs to be rejected anyway, because it is far too simplistic. But note that we can construct analogous cases for any theory that allows for the possibility that a person knows that her reasons require her to refrain from the option with the highest expected reasons-responsiveness. This can be avoided by a view according to which the actual degree of reasons-responsiveness does not come apart from the expected reasons-responsiveness relative to the agent's mental state, and this will necessarily be a view according to which reasons-responsiveness supervenes on the mind. On such a view, the option with the highest degree of reasons-responsiveness will automatically be the option with the highest expected reasons-responsiveness, and since on no coherent view do reasons require one to refrain from the option with the highest degree of reasonsresponsiveness, it follows that reasons cannot require one to refrain from the option with the highest expected reasons-responsiveness. In contrast, if reasons-responsiveness does not supervene on the mind, there will be situations in which our reasons require us to refrain from the option with the highest expected reasons-responsiveness. It seems to me that any such view faces the objection from recklessness, because no such view can avoid the implication that reasons require us to be reckless. Moreover, proponents of a view of this kind can avoid the objection from enkrasia only if they are able to explain why, even though our reasons might in fact require us to refrain 7 See Kiesewetter (2017, Ch. 8; 2018b) for a (much more detailed) version of this argument that targets views that reject an epistemic constraint on reasons. I here try to show that a structurally analogous argument provides at least a challenge for all views that do not accept that reasons-responsiveness supervenes on the mind. Broome presents a similar argument in order to show that in "situations where consequentialism applies" (Broome 2013, 36), we ought – in the sense relevant for the enkratic principle – to choose the option with the best prospects rather than the best outcome. My example does not involve assumptions about value or expected value, and so my argument does not depend on whether or not consequentialism applies. 8 from the option with the highest expected reasons-responsiveness, we cannot be in the position to know that they do. In any case, the view that reasons-responsiveness supervenes on the mind allows for a simple and attractive solution to the problems that three-option cases raise for other views, by enabling us to say that reasons cannot require us to refrain from the option with the highest expected reasons-responsiveness. This is a good reason, independent of considerations concerning the nature of rationality, to take it seriously and see whether it can be defended. III Broome offers two major arguments against the thesis that reasons-responsiveness supervenes on the mind. The first is that this thesis conflicts with the common assumption that external facts can be reasons; the second is that it conflicts with the existence of reasons to perform actions in the external world (such as insuring a house). As far as this second argument is concerned, I don't find it obvious that whether or not we respond correctly to reasons for external actions does not supervene on the mind. There may well be a systematic connection between reasons for actions and reasons for intentions, such that a failure to respond to the former entails a failure to respond to the latter, and this connection might explain why responsiveness to reasons for action supervenes on the mind if responsiveness to reasons for mental states supervenes on the mind.8 But suppose that Broome is right and the existence of reasons for external actions conflicts with the thesis that reasonsresponsiveness supervenes on the mind. We might then simply exclude reasons for action from the analysans of rationality by defining it in terms of responsiveness to reasons for mental states. This view would still seem to have all the general attractions mentioned in the beginning of this paper.9 8 There is no space to defend this here, but I am sympathetic to the principle that A ought to perform a nonmental action F only if there is a mental state M such that (i) A ought to be in M, and (ii) if A is in M, then A F-s. This principle entails that responsiveness to reasons for non-mental actions supervenes on the mind if responsiveness to reasons for mental states supervenes on the mind. 9 In fact, the view that I proposed in Kiesewetter (2017, 162) is restricted to reasons for mental states. 9 So the real challenge for rationality as reasons-responsiveness is not to accommodate reasons for external actions, but to accommodate reasons that are constituted by external facts – "external reasons" as Broome calls them.10 To illustrate this challenge, consider Goodsmith and Badsmith, two detectives who are looking for a murderer in the woods. Goodsmith and Badsmith share all mental properties but live in slightly different possible worlds. Both have the same perceptual seeming of someone disappearing behind a tree, but only Goodsmith's seeming is veridical. That someone disappeared behind the tree is part of Goodsmith's evidence, and we can truly cite it as a reason for her to believe that the murderer is hiding behind the tree. Given further background assumptions, it might be that because of this reason, Goodsmith's reasons require her to believe that the murderer is hiding behind the tree, and hence that Goodsmith is reasons-responsive only if she believes that the murderer is hiding behind the tree. But the same cannot be said about Badsmith. Since no one disappeared behind a tree in her world, that someone disappeared behind a tree is not a reason for her. For all that has been said so far, Badsmith might have no reason to believe that the murderer is hiding behind the tree, and we cannot conclude that she is reasons-responsive only if she has this belief. Thus, it looks like even if Goodsmith and Badsmith share all mental properties, Badsmith may be reasons-responsive while Goodsmith isn't. What could explain that Goodsmith and Badsmith cannot differ with respect to their reasons-responsiveness even though they differ with respect to their reasons? The first step towards such a conception of reasons-responsiveness is to restrict the relevant reasons to the class of reasons that are available to us. We might argue substantively that only reasons in this sense can contribute to what we ought to do or believe in the sense in which we are asking the questions "What ought I to do?" or "What ought I to believe?" in deliberation.11 Or we might simply stipulate that the relevant notion of reasons-responsiveness for the analysis of rationality is responsiveness to available reasons. But what does availability require? As I have suggested elsewhere, p is an available reason for an agent only if the assumption that p is supported by A's total phenomenal state, which includes sensory experiences, perceptions, introspections, memories, but also 10 I shall adopt Broome's usage of the term 'external reason', even though it differs in crucial ways from other important ones, such as Williams' (1979). 11 See e.g. Kiesewetter (2011; 2018b). 10 intellectual seemings or intuitions.12 It follows from this that the fact that someone disappeared behind the tree is an available reason for Goodsmith to believe that the murderer is hiding behind the tree only if her total phenomenal state supports the assumption that someone disappeared behind the tree. And since her phenomenal state does not differ from Badsmith's, it also follows that Badsmith's phenomenal state supports the same assumption. The second step involves the assumption that phenomenal states do themselves provide reasons, and that these reasons ensure that whatever attitudes are on balance supported or required in the good case are also supported or required in the bad case. For simplicity, I will here focus on the attitude of belief: The backup view: If A's total phenomenal state supports assumptions [r1, ..., rn], and [r1, ..., rn] would – if true – provide sufficient (or decisive) reason for A to believe p, then A's appearances also provide sufficient (or decisive) reason to believe p. According to the backup view, appearances provide backup reasons for our primary reasons, which are typically constituted by external facts.13 In previous work I suggested that backup reasons and primary reasons are equally strong, but here I want to stay less committal.14 What is essential for the backup view is not that the reasons in the good and the bad case are equally strong, but only that the reasons support and require the same responses in both cases. The former assumption is a natural explanation for the truth of the latter, but there may be other explanations that I do not wish to exclude. The backup view entails that Goodsmith's reason to believe that the murderer is hiding behind the tree corresponds to a reason on Badsmith's side, and that if the former reason is sufficient (or decisive), so is the latter. This explains why, even though Badsmith lacks a reason that Goodsmith has, their balances of reasons favour the same beliefs and one is reasonsresponsive if, and only if, the other is. In this way, the backup view allows us to have it all: internalism about rationality, externalism about reasons, and rationality as reasons- 12 Cf. Kiesewetter (2017, 173). As far as I can see, the support relation invoked by this condition may be understood either in terms of a non-normative relation of evidential probabilisation, or in terms of reasons for belief. 13 Not all primary reasons are provided by external facts. For example, the fact that you have a headache may be a primary reason. 14 See Kiesewetter (2017, 173). 11 responsiveness – three views with enormous initial plausibility. But perhaps this is too good to be true? IV Broome presents two objections to the backup view. His first objection is that the backup view entails that external reasons have no weight, which makes the appeal to such reasons seem "like a sham" (Broome forthcoming, 10). As I understand him, he argues as follows. If Badsmith has an appearance, so does Goodsmith, and if Badsmith's appearance provides a reason, so does Goodsmith's. So Goodsmith has all the reasons that Badsmith has for believing that the murderer is hiding behind the tree, plus the external reason. Given this, to assume that Goodsmith and Badsmith have equally strong reason for believing that the murderer is hiding behind the tree "seems to imply that the [external reason] has no weight" (ibid.). One way to deal with this objection would be to grant that Goodsmith must have on balance stronger reason than Badsmith and provide an explanation of why their reasons are nevertheless equally sufficient or decisive. But I think that the objection fails even if we suppose that Goodsmith's and Badsmith's reasons are equally strong. The objection assumes that Goodsmith's external reason has weight only if the combined weight of the external and the backup reason is higher than the weight of the backup reason. In other words, it assumes that primary reasons and their backup reasons allow for aggregation. But this assumption should be rejected. Compare the following case, which is independent of the commitments of the backup view. Your neighbour (a reliable person, etc.) tells you that she has seen people shopping in the grocery store, and her testimony provides a reason to believe that the store is open. Now contrast a good case, in which your neighbour has in fact seen people shopping, with a bad case, in which your neighbour is mistaken, and no one was shopping in the store. Suppose that in the good case, you come to know by testimony that people were shopping in the store. Plausibly, the fact that people were shopping in the store is now itself a reason for you to believe that the store is open. But what should we say about the fact that your neighbour told you that she has seen people shopping in the store – does it still provide a reason in the good 12 case? However we answer this question, it seems clear that if your neighbour's testimony still counts as a reason in the good case, it cannot be aggregated with the reason provided by the fact that people were shopping. I believe that the same holds for backup and primary reasons. If the appearances provide a backup reason in the good case, it cannot be aggregated with the primary reason. In general, reasons allow for aggregation only if they are sufficiently independent. This is not the case, for example, when one reason derives from the other, or two reasons derive from the same source reason.15 The fact that Andreas is losing blood is a reason to call the emergency line. The fact that Andreas had an accident is also a reason to call the emergency line. Each of these reasons has non-zero weight, but since both derive from the same source, their weights cannot be combined. The testimony case provides another case of dependency, which may be captured by the following principle: Evidential dependency: If E provides a reason to believe q because (i) E is evidence for p, and (ii) p is, if true, a reason to believe q, then E and p do not provide independent reasons to believe q. Plausibly, testimony that people are shopping provides a reason to believe that the store is open only because (i) it is evidence that people are shopping at the store, and (ii) if people are shopping at the store, this is a reason to believe that the store is open. The testimony-based reason does not derive directly from the reason provided by the testified fact (as the former reason can be present without the latter), but it is dependent in the sense that it is to be explained by its evidential relation to the testified proposition p, together with what Scanlon calls the "purely normative" reason claim that "whether p obtains or not, should p hold then it is a reason" (Scanlon 2014, 36–37). If a reason is dependent in this way, it does not allow for aggregation with a reason provided by the fact that p. The same reasoning also explains why backup reasons do not aggregate with primary reasons. An appearance that p provides a backup reason to believe q in virtue of the fact that (i) the appearance provides evidence for p, and the purely normative truth that (ii) p is, if true, a reason to believe q. So if the appearance that someone disappeared behind the tree 15 For further discussion and references, see Kiesewetter (2018a, §3). 13 provides a reason for Goodsmith, this reason cannot be aggregated with the reason provided by the fact that someone disappeared behind the tree. Importantly, it does not follow that either of these reasons lacks weight. The weight of a reason is a matter of how it combines with independent reasons and how it fares with competing reasons. The primary, external reason provided by the fact that someone disappeared behind the tree allows for aggregation with independent reasons for believing that the murderer is hiding behind the tree, and it can be weighed against competing reasons. That it doesn't allow for aggregation with a dependent reason does nothing to show that it has no weight. For this reason, Broome's objection fails. V Let's turn to Broome's second objection to the backup view, which is based on a counterexample that is a variation of the murderer hunt case. Broome introduces two amendments to the case: First, Goodsmith and Badsmith know that apart from themselves, the only other person that could be nearby is the murderer. Second, both have received "a fairly reliable report that the murderer was recently seen in a distant city" (Broome forthcoming, 10). Broome now argues that on these assumptions, Goodsmith ought to believe that the murderer is hiding behind the tree, while it's not the case that Badsmith ought to believe this, which is incompatible with the backup view (and directly rules out that reasonsresponsiveness supervenes on the mind). As I understand the structure of his counterexample, Broome presents a defeater that is supposed to be effective in the bad case but not in the good case. Broome's second amendment (the report that the murderer was seen elsewhere) introduces the defeater. The first amendment (knowledge that the murderer is the only person who could be nearby) is supposed to protect Goodsmith's reason from being defeated, without protecting Badsmith's reason. It does so by ensuring that the supported belief (that the murderer is hiding behind the tree) is entailed by Goodsmith's evidence (which now includes the fact that someone is hiding behind the tree and the fact that the murderer is the only person who could be nearby), but not entailed by Badsmith's evidence, which doesn't include the fact that someone is hiding 14 behind the tree, but only the appearance of someone hiding. The idea at work here is that if your evidence entails p, then the reasons it provides for believing p cannot be defeated by competing reasons. In contrast, if your evidence supports a proposition while falling short of entailing it, then nothing in principle prevents the reasons it provides from being outweighed. According to Broome, Badsmith's appearance-based reason for believing that the murderer is hiding behind the tree is defeated by the evidence indicating that the murderer was recently seen in a distant city, while Goodsmith's reason is still conclusive. My reply is that if the evidence provided by the report effectively defeats Badsmith's appearance-based reason, it thereby also undermines the appearance's credibility. And if the report undermines the credibility of Badsmith's appearance, it also undermines the credibility of Goodsmith's appearance. But if the credibility of Goodsmith's appearance that someone disappeared is undermined by her evidence, it no longer seems plausible to assume that the fact that someone disappeared behind the tree is among Goodsmith's available reasons, and Goodsmith's reasons no longer entail that the murderer is hiding behind the tree. This response can be generalized. Whenever q is entailed by p, whatever defeats a reason to believe q in the bad case thereby also undermines the credibility of an appearance that p and thus the availability of p as a reason to believe q in the good case. For this reason, I do not think that the backup view is vulnerable to the kind of counterexample presented by Broome. VI Broome argues that rationality cannot consist in reasons-responsiveness since rationality supervenes on the mind, while reasons-responsiveness does not supervene on the mind. I have here defended this conception of rationality by way of defending the assumption that reasons-responsiveness supervenes on the mind. Given the many advantages of an analysis of rationality in terms of reasons-responsiveness, and in light of independent considerations in favour of the view that reasons-responsiveness supervenes on the mind, we should take seriously the backup view, a hypothesis that explains why reasons-responsiveness supervenes on the mind even though paradigmatic reasons are external facts. I have argued that Broome's 15 objections to the backup view, as well as his more general objection to the thesis that reasonsresponsiveness supervenes on the mind, do not succeed.16 References Broome, John. 2007. 'Is Rationality Normative?' Disputatio 2 (23): 161–78. ---. 2013. Rationality Through Reasoning. Chichester: Wiley-Blackwell. ---. n.d. 'Rationality versus Normativity'. Forthcoming in: Australasian Philosophical Review. Dancy, Jonathan. 2004. 'Enticing Reasons'. In Reason and Value. Themes from the Moral Philosophy of Joseph Raz, edited by R. Jay Wallace, Philip Pettit, Samuel Scheffler, and Michael Smith, 91–118. Oxford: Oxford University Press. Hume, David. 1739. A Treatise of Human Nature. Edited by L.A. Selby-Bigge. 2nd ed. Oxford: Oxford University Press (1888/1978). Jackson, Frank. 1991. 'Decision-Theoretic Consequentialism and the Nearest and Dearest Objection'. Ethics 101 (3): 461–82. Kiesewetter, Benjamin. 2011. '"Ought" and the Perspective of the Agent'. Journal of Ethics and Social Philosophy 5 (3): 1–24. ---. 2017. The Normativity of Rationality. Oxford: Oxford University Press. ---. 2018a. 'Contrary-to-Duty Scenarios, Deontic Dilemmas, and Transmission Principles'. Ethics 129 (1): 98–115. ---. 2018b. 'How Reasons Are Sensitive to Available Evidence'. In Normativity: Epistemic and Practical, edited by Conor McHugh, Jonathan Way, and Daniel Whiting, 90–114. Oxford: Oxford University Press. Kolodny, Niko. 2005. 'Why Be Rational?' Mind 114 (455): 509–63. Lord, Errol. 2018. The Importance of Being Rational. Oxford: Oxford University Press. Parfit, Derek. 2011. On What Matters. Vol. 1. Oxford: Oxford University Press. Scanlon, T.M. 2014. Being Realistic about Reasons. Oxford: Oxford University Press. Williams, Bernard. 1979. 'Internal and External Reasons'. Reprinted in Moral Luck, 101–13. Cambridge: Cambridge University Press (1981). 16 Earlier versions of this paper have been presented and discussed at Humboldt-Universität zu Berlin, University College London, and the University of Southampton. I would like to thank the participants for their valuable feedback. I am especially grateful to Garrett Cullity, Philip Fox, Jan Gertken, Alex Gregory, Felix Koch, Sebastian Schmidt, and Nicholas Southwood for written comments. Work on this paper has been supported by the Deutsche Forschungsgemeinschaft (DFG Project "Principles of the Deliberative Ought").