Disgust as Heuristic Robert William Fischer Forthcoming in Ethical Theory and Moral Practice Abstract Suppose that disgust can provide evidence of moral wrongdoing. What account of disgust might make sense of this? A recent and promising theory is the social contagion view, proposed by Alexandra Plakias. After criticizing both its descriptive and normative claims, I draw two conclusions. First, we should question the wisdom of drawing so straight a line from biological poisons and pathogens to social counterparts. Second, we don't need to explain the evidential value of disgust by appealing to what the response tracks. These lessons point toward an alternative: namely, that disgust is a moral heuristic. On the heuristic view, disgust is a trigger for the subconscious use of a particular rule: < If x is disgusting, and we wouldn't do x, then x is morally wrong. > I show how this view fits with a plausible hypothesis about the social function of disgust, and then apply it as well as how it sheds light on Leon Kass's famous use of repugnance to criticize cloning. Kewords disgust; social contagion; Alexandra Plakias; Leon Kass; moral heuristics 1 Disgust and Morality Should we let our disgust guide our moral judgments? Some think not. Martha Nussbaum, for example, maintains that disgust is "especially likely to be normatively distorted," and she submits that it is "problematic and irrational... across the board" to use it as a guide to wrongness (2004: 102). Likewise, Daniel Kelly argues on evolutionary grounds that disgust "is not wise about or acutely attuned to ethical considerations, and "yuck" deserves no special moral credence; rather, repugnance is simply irrelevant to moral justification" (2011: 147).1 Accordingly, let's say that disgust skepticism is the following view: This paper was much improved by the efforts of two anonymous reviewers. I'm also indebted to Elisa Aaltola, Ben Bramble, John Hadley, Burkay Ozturk, Isaac Wiegman, and a helpful audience at the 2015 meeting of the APPE. 1 For similar sentiments in Kekes (1992), Corvino (1997, 2013), Knapp (2003), Singer (2005), and Greene (2008). 2 We aren't justified in believing that actions are wrong based on their being disgusting. Philosophers who endorse disgust skepticism offer several reasons in its favor. First, they note disgust's false positives-such as people being disgusted by, and therefore condemning, gay sex or interracial marriage (Corvino 2013). Second, they call attention to its association with dehumanization. Infamously, the Nazis used the rhetoric of repugnance to help justify "the Final Solution," which is standard fare among those who have pursued genocidal projects (Nussbaum 2004). Third, they point out that its evolutionary history doesn't provide reason to think that it's sensitive to morally-relevant properties, as disgust probably developed to help our ancestors avoid the oral incorporation of harmful substances (Kelly 2011). Finally, they point to the immense variation in what we find disgusting, which gives us reason to doubt that disgust tracks wrongness (Kelly and Morar 2014). But disgust has defenders too.2 In short, they reply that these objections either show too much or too little. The "too much" charge is that these objections show that we can't trust any of our emotions, since they all admit false positives, can be associated with serious wrongdoing, have evolutionary histories that don't perfectly match their current moral use, and vary considerably in their application across cultures. The "too little" charge is that these objections only show that disgust can lead us astray in moral matters, not that it usually does. If these replies are successful, then they make room-but do not directly support-the disgust advocate's position: Sometimes, we are justified in believing that actions are wrong based on their being disgusting. To make this position plausible, we need a model of disgust that forges the right sort of link between disgust and moral justification. My aim here is to sketch a view of disgust that does just that. So in the first part of the paper, I consider an instructive attempt. Alexandra Plakias (2013) suggests that the disgust advocate needs to "identify some property that disgust is tracking-and show that some things do have that property" (2013: 273). Given as much, she proposes that "[t]he disgust advocate's strongest argument [...] is that moral disgust [...] tracks, and presents its elicitor as possessing, social contamination and contamination 2 See, e.g., Hauskeller (2006), Curtis (2011), Demetriou (2013), Plakias (2013), Clark and Fessler (2014), Clark (2015), and Besong (forthcoming). 3 potency" (2013: 276).3 I contend that the disgust advocate shouldn't argue this way. On the one hand, the descriptive claim is either implausible or purely speculative. On the other, the proposal doesn't make it easy to see how disgust is evidence, since it isn't clear that wrongness and social contamination are appropriately related. Still, these problems point the way forward, providing some reason for the advocate to rethink the connection between disgust's biological function and justificatory role in ethics. In the second part of the paper, I develop a better way of viewing disgust's moral significance-namely, seeing it as a moral heuristic. 2.1 Plakias's Proposal on Behalf of the Disgust Advocate Rozin and Fallon (1987: 23) define "core" disgust as "[r]evulsion at the prospect of (oral) incorporation of an offensive object. The offensive objects are contaminants; that is, if they even briefly contact an acceptable food, they tend to render that food unacceptable." This definition hints at their theory of the origin of disgust. On their view, the disgust response evolved to help our omnivorous (and scavenging) ancestors avoid food-born poisons and pathogens by discouraging their oral incorporation. The disgust response managed this in three ways. First, it discouraged disgusted individuals from coming into contact with harmful substances. Second, it helped our ancestors expel harmful (or potentially harmful) substances should contact have occurred-e.g., by gagging and vomiting. Third, it involves a signaling mechanism: the associated gape face is universally recognizable, leading others to avoid the relevant substances too. Given the stakes, false positives are much worse than false negatives. One way to prevent false negatives is to have a response that can be elicited by new objects very quickly, in case poisons or pathogens are somehow transferred from one object to another. After all, natural selection isn't going to write a script that says, < if x is a stick, then x is disgusting >. But if you know that a stick has been sitting in feces, then you'll tend to find the stick disgusting too, even if that waste isn't detectable on it. Hence, we might say that being disgusting is a contagious property: if something is disgusting, that repugnance transfers to those objects it touches. Importantly, such cognitive scripts can be both restricted and extended. Perhaps evolution wrote a script that says, < if slimy, then disgusting >, but the Japanese have restricted it so that it doesn't apply to natto-a stringy and pungent 3 Plakias doesn't explicitly endorse the disgust advocate's position, so it's probably best to read her as defending a conditional: if you think that the disgust advocate's position is true, then you should opt for the view that moral disgust tracks, and presents its elicitor as possessing, social contamination and contamination potency. 4 fermented soybean product-and Sardinians have restricted so that it doesn't apply to Casu Marzu-a maggot-filled cheese. Likewise, evolution surely didn't write a script that says, < if food and on the ground, then disgusting >. But our disgust response is, in part, informed by the germ theory of disease. So we think that candy is yucky after it's hit the floor, and we teach our children to react in kind. As Daniel Kelly (2011) argues, disgust's flexibility means that it can be co-opted for other purposes, such as regulating human social interactions. Of course, there is considerable variation between individuals and across cultures in terms of (a) how "disgustable" people are-i.e., how prone they are to be disgusted, (b) which actions people find disgusting, and (c) how much weight people place on disgust when making moral judgments. Still, people certainly report being disgusted by certain actions, and there appear to be good reasons to take their reports to be accurate (i.e., they aren't-or aren't always-confusing disgust with anger, as Chapman and Anderson (2013) argue). Moreover, their responses seem to play important role in their moral assessments (as Haidt (2001, 2012) argues). In light of the above, how might someone develop the disgust advocate's position? Here is Plakias's proposal: The disgust advocate's strongest argument [...] is that moral disgust has morally relevant representational content: it tracks, and presents its elicitor as possessing, social contamination and contamination potency. But [...] not all contagion is bad contagion. Contagion itself is neither good nor bad; it is the attitudes and behaviors in question that make something contaminating in a deleterious sense. [...] The question of whether some behavior or attitude has the kind of contamination potency disgust ascribes to it [...] can be disambiguated into the question of whether the behavior has potentially deleterious effects and the question of whether the behavior is contagious. Likewise, the question of whether moral disgust is an appropriate response to some act can be disambiguated into the question of whether that act is really immoral, and whether the act is potentially contaminating. But the former is a question for normative ethics, and not for moral psychology (2013: 276). Let's call this "the social contagion view." According to the social contagion view, while disgust might still help us avoid biological poisons and pathogens, it now helps us avoid social poisons and pathogens too. It does this by way of an 5 aversive response to behaviors (or beliefs or attitudes) that have contamination potency. By this, Plakias just means that the behavior is especially shareable. In other words, your being in the presence of that behavior increases the likelihood that you will act similarly. Crucially, Plakias isn't saying that moral disgust tracks all social contagion. Not all contagion is bad contagion: research on happiness, for example, suggests that it too "could be thought of as a form of social infection" (Hill et al. 2010: 3828). However, disgust clearly represents its object in an unfavorable light, so the proposal is that disgust tracks actual social contagion that the agent perceives as negative.4 Of course, we can go on to consider whether there are independent reasons to affirm the agent's negative assessment of the contagious action (or belief, or desire, or what have you). Presumably, the advocate thinks that there often are such reasons. But even if not, disgust can still provide prima facie evidence of wrongness insofar as it's tracking a property that's relevant to the wrongness-namely, the ostensibly-negative contagiousness. Hence, it can provide justification for the belief that the relevant behavior (or what have you) is wrong. 2.2 Evaluating the Descriptive Claim The social contagion view has two parts: a descriptive claim and a normative claim. The descriptive claim concerns what disgust tracks-namely, negatively perceived contagion. The normative claim is that negatively perceived contagion is evidence of wrongness. Our focus in this section is the descriptive part of the theory. Someone might think that the descriptive part of theory is trivially true. It's hard to imagine morally disgusting behavior that wouldn't be negatively perceived. And given that most behavior is contagious, that too looks like an uncontroversial claim. However, the descriptive part of the social contagion view is not trivially true, as I'll now argue. An initial problem with the descriptive claim concerns the strength of the relation it posits between disgust and negatively perceived social contagion: namely, that the former tracks the latter. The standard way to flesh out the claim that x tracks y uses the following counterfactuals: if y were the case, then x would be the case; and if y weren't the case, then x wouldn't be the case.5 4 Plakias has confirmed this interpretation in correspondence. 5 The literature on tracking goes back to Nozick (1981). 6 So we get: if z were negatively perceived and social contagious, then we would find z morally disgusting; and if z were morally disgusting, then z would be negatively perceived and socially contagious. So construed, the view is very implausible. Here, for example, are some counterexamples to the first counterfactual: not declaring your tips on your taxes; using office supplies from work for personal purposes; "borrowing" ideas from websites without citing; sharing gossip that you'd promised not to share; using plastic instead of reusable bags at the grocery store; eating animal products that you know were sourced from factory farms; and laughing at jokes that play on racial or gender stereotypes. I doubt that these are exceptional cases. Indeed, I suspect that most negatively perceived behaviors are socially contagious, at least to some degree or other, and it's plain that disgust is only marshalled against a few of them. (To be clear, the social contagion isn't a function of the negativity, but of the fact that behavior is contagious generally. As Plakias herself observes, "[that] people are influenced by the behaviors of those around them isn't surprising; after all, it's what makes imitative learning possible" (2013: 275).) But we can be more charitable. Suppose we drop the first counterfactual and reinterpret the second probabilistically. This gives us the tendency version of the descriptive claim: If z is morally disgusting, then z tends to be negatively perceived and socially contagious. Is the tendency version of the descriptive claim true? Probably not. Most morally disgusting behavior isn't socially contagious precisely because it's disgusting. News reports of bestiality don't promote bestiality; after disgust has been marshalled to discourage certain behaviors, encountering it doesn't increase the odds that we'll imitate them. In general, we aren't inclined to act in ways that we judge to be repugnant. 7 However, this is a fixable problem. We can patch the tendency version by adding a counterfactual clause: If z is morally disgusting, z tends to be such that (a) z is negatively perceived and (b) z would have been social contagious were disgust not marshalled to discourage it. Let's call this the counterfactual version of the descriptive claim." Is it true? I'm not sure. To see why you might doubt it, consider the story of Armin Meiwes (recounted in Haidt 2012: 146): In early 2001, Armin Meiwes, a German computer technician, posted an unusual advertisement on the Web: "Looking for a wellbuilt 21-to-30-year-old to be slaughtered and then consumed." Hundreds of men responded by email, and Meiwes interviewed a few of them at his farmhouse. Bernd Brandes, a forty-three-yearold computer engineer, was the first respondent who didn't change his mind when he realized that Meiwes was not engaging in mere fantasy. [...] On the evening of March 9, the two men made a video to prove that Brandes fully consented to what was about to happen. Brandes then took some sleeping pills and alcohol, but he was still alert when Meiwes cut off Brandes's penis, after being unable to bite it off (as Brandes had requested). Meiwes then sautéed the penis in a frying pan with wine and garlic. Brandes took a bite of it, then went off to a bathtub to bleed to death. A few hours later Brandes was not yet dead, so Meiwes kissed him, stabbed him in the throat, and then hung the body on a meat hook to strip off the flesh. Meiwes stored the flesh in his freezer and ate it gradually over the next ten months. This strikes me as a paradigmatic instance of morally disgusting behavior. Moreover, we should expect it to be disgusting: the case involves sex, mutilation, and death-known triggers of disgust (see Rozin, Haidt, and McCauley 2008). Still, it seems doubtful that this behavior would spread even if disgust weren't marshalled against it. This is partially because of the strength of our impulse to survive, but also because the contagion is self-undermining. Those who would adopt these practices (already on a tail of some bell curve) wouldn't last for long. Half of them would be dead, and we'd distance ourselves from the rest-or corral them-simply on the basis of the harm they'd caused. It wouldn't matter whether we found their actions disgusting. Moreover, it isn't clear that this case is unique; 8 similar things may well be true of other extremely violent actions. Though disgust has been co-opted to make us averse to them, it isn't plain that it was needed for that purpose. If we weren't disgusted by such actions, we might well be angry about them instead, and anger might be just as good as preventing social contagion. Perhaps such issues can be finessed. My point here isn't that the counterfactual version of the descriptive claim is false. Rather, it's that it isn't obviously true: it's a substantive empirical hypothesis that stands or falls on some speculations about what would happen if we weren't disgusted by things that we currently find disgusting. However, it may well be the case that non-contagion is overdetermined-i.e., the action in question wouldn't be contagious even if we weren't disgusted by it, since there are multiple mechanisms that prevent it from spreading. Alternately, it may be the case that we'd have some other strong reaction (e.g., anger) if we weren't disgusted which would be just as good at preventing contagion. Absent some reason to think that disgust is the sole mechanism that does and could prevent contagion, we should be wary of resting too much on any version of the descriptive claim. 2.3 Evaluating the Normative Claim The normative part of the social contagion view is that negatively perceived social contagion is evidence of wrongness. In the interest of assessing the normative claim, let's grant the counterfactual version of the descriptive claim. It seems to me that the normative claim faces a dilemma. Either social contagion is supposed to explain the relevant wrongness, or it isn't. There are problems either way. Suppose it is, as Plakias's characterization of the view might suggest. (Recall: "moral disgust has morally relevant representational content.") Then, we have a clear story about how disgust could provide evidence: it tracks a wrongmaking property, and so is evidence of wrongness. But to see whether it in fact does, we have to check the cases. In general, can we explain the wrongness of disgusting actions in terms of the hypotheses that they would have been social contagious if disgust hadn't been co-opted to discourage them? It's hard to see how. Take any disgusting action you like: why should a property that it would have had be relevant to whether it's actually wrong? Indeed, that the action isn't socially contagious seems like an important respect way in which it isn't wrong. If a bad act caused others to behave badly, that would be an additional respect in which it was bad. That it doesn't cause others to behave badly is a respect in which it isn't bad. 9 At this point, we might be tempted to revert to the simpler, tendency version of the descriptive claim, maintaining that disgust provides evidence of wrongness because it provides evidence of actual social contagion. But even if the tendency version can be salvaged-and I'm not sure it can-actual social contagion probably won't be the whole story about the wrongness of acts, or even the most important part of the story. Consider, for example, the crime of Johnny Ray Johnson: Johnson was convicted and sentenced to death for the March 27, 1995 capital murder of Leah Joette Smith during the course of committing or attempting to commit aggravated sexual assault. [...] Johnson offered to give Smith, who was addicted to crack cocaine, some crack cocaine in exchange for sex. After Smith smoked the crack, she refused to have sex with Johnson. He became angry and grabbed her, ripped her clothing off, and threw her to the ground. When she fought back with a wooden board, Johnson repeatedly struck her head against the cement curb. After he hit her head against the cement three or four times, she stopped fighting. He then sexually assaulted her. [Afterward,] Johnson stomped on her face five or six times. He walked away, but realized that he had left his wallet at the scene, so he returned. In his confession, he stated that when he saw Joette's body face up and naked, he sexually assaulted her again and then picked up his wallet and her boots and left Smith there on the ground to die.6 Johnson's actions are repugnant; they were also clearly wrong. Were they wrong because of the contagion potential? Perhaps, but that isn't the explanation that leaps to mind. That explanation is going to be in terms of the great harms to Leah Joette Smith, as well as his callousness, cruelty, and apparent sexual sadism. It does seem plausible that encouraging others to act wrongly is itself wrong-it's bad to promote the bad. But there seems to be a mismatch between this point and the force of the disgust response. Even if no one were inclined to imitate Johnson, we'd condemn him just as forcefully. So while contagion might add to the wrongness, it seems unlikely that it adds much. With that in mind, let me propose a principle for assessing theories of moral disgust: all else equal, we should favor a theory of moral disgust that explains why it's triggered by offenses that the disgusted party tends to regard as very serious. According to this version of the social contagion view, moral disgust 6 Johnson v. Quarterman, 483 F.3d 278 (5th Cir. 2007) (Habeas). Retrieved from http://www.leagle.com/decision/2007761483F3d278_1761 on November 3, 2013. 10 is supposed to provide evidence of wrongness because it's triggered by social contagion, where that property is supposed to explain the wrongness of the act in question. And in Johnson's case, it doesn't explain much. So, the social contagion view doesn't do very well by the lights of this principle. Perhaps we can revise the social contagion view so that it doesn't say that would-be or actual social contagion plays any role in the explanation of the wrongness of the relevant act. In that case, let's turn to the other horn of the dilemma. We're now assuming that the wrongness of the disgusting act is to be explained on other grounds. But then disgust is evidence of wrongness only if we have reason to believe one of two hypotheses: 1. When actions are negatively perceived and social contagious, they tend to be wrong. 2. When actions are negatively perceived and would have been socially contagious, were disgust not marshaled to discourage them, they tend to be wrong. Hypothesis #1 is probably true. However, it has nothing to do with disgust-recall the examples that led us to the tendency version of the descriptive claim, such as not declaring your tips on your taxes. What's more, it fails to explain why disgust is directed toward offenses that people perceive as being very serious. Hypothesis #2 is too speculative to assess. We just don't know which actions would have been socially contagious if disgust hadn't been marshaled to discourage them, as I argued at the end of the last section. So, we're in no position to assess whether those actions tend to be wrong.7 3.1 Beyond the Social Contagion View Let's sum up the discussion thus far. The original version of the social contagion view rests on a descriptive claim that's too strong. Once we weaken it- generating the tendency version-we see that it's implausible. We can patch it- generating the counterfactual version of the descriptive claim-but now there's no reason to believe it. Moreover, if the normative claim is true, then either (a) social 7 If the disgust advocate takes the "social contagion doesn't explain" horn of the dilemma, then it might be more charitable to construe the view as a version of phenomenal conservatism in ethics (à la Huemer 2005): if it seems to you that x is morally wrong, then that is some evidence that x is indeed wrong. On such a view, we don't need an argument to the effect that negatively-perceived social contagion is correlated with a wrong-making property. At the same time, though, disgust isn't evidence. Rather, it's seeming to you that p is your evidence, and that seeming happens to be accompanied by a visceral reaction. This is fine as far is it goes, but it isn't what we were promised. 11 contagion should explain why actions are wrong or (b) there ought to be some correlation between social contagion (whether actual or counterfactual) and wrongness. However, neither is plausible. Plakias suggests that the social contagion view is the disgust advocate's best option. If she's right about that, then things aren't looking so good for the disgust advocate. Is there an alternative? I think so. Before sketching it, though, we need to learn some lessons from the social contagion view. On the descriptive side, we should note that it's reasonable to develop an account of disgust's moral significance based on an analogy with its biological significance, as Plakias does. But to be adaptive, disgust doesn't need to track anything, nor even reliably indicate that a certain property is present. Instead, it just needs to give disgustable beings a fitness advantage over non-disgustable beings. Of course, it might do this by tracking a property, as vision does-at least for reasonably close middle-sized dry goods. However, we needn't suppose as much at the outset, and the troubles with the social contagion view give us reason to question the wisdom of drawing so straight a line from biological poisons and pathogens to social counterparts.8 A better option may be to think about moral disgust functionally. Given what we know about it, what end could it serve? On the normative side, we too should be careful to separate the descriptive and normative elements of our theory of disgust, just as Plakias recommends. But the normative part of the social contagion view still depends on social contagion being morally relevant-or, if it doesn't, we aren't in a position to assess the normative part. Given the difficulties we've seen with that hypothesis, it might be better to separate the descriptive and normative claims even more. It would be hard to tell a story about moral disgust where what triggers it plays no role in accounting for its evidential value, but it may be possible to tell a story where it plays a minor role, and some other mechanism does the justificatory work. Before trying to offer such an account, we need to consider two questions that help to put moral disgust in perspective. First, what are moral emotions, at least from an evolutionary perspective? Very roughly, the answer is that the moral emotions are instances of what Daniel Kahneman (2011) calls fast thinking. That is, emotions like disgust, empathy, shame, guilt, and anger are instances of fast and effortless information processing. They are distinguished from other instances of fast thinking by their affective dimension. These quick responses to stimuli increase the odds that agents will behave in certain ways. Some emotions-like fear, which encourages avoiding high-risk situations-benefit the organism directly. But moral emotions tend to be other-directed, benefiting in-group 8 We might also worry about how well we can unpack the metaphor, as attractive as it is. But I'll leave this aside here. 12 members. Insofar as the well-being of group is in the interest of the individual, these emotions provide indirect benefits, and thus contribute to fitness in a roundabout manner. As Joshua Greene puts it, moral emotions are "psychological adaptations that allow otherwise selfish individuals to reap the benefits of cooperation" (2013: 23). Granted, evolution doesn't promote selfishness by default, even if it's helpful to model some episodes in evolutionary history that way. Likewise, it isn't part of this view that people are motivated by self-interest (enlightened or otherwise) when they cooperate. Rather, the idea is that evolution outfitted our ancestors with genuinely other-directed concerns because doing so was fitness-enhancing: those concerns spared our ancestors from prisoners' dilemmas and related non-zero-sum interactions where acting selfishly is a bad long-term strategy. That is, our ancestors acquired emotional dispositions that made them less likely to satisfy immediate interests at the expense of others- including their future selves-and more likely to act in ways that are mutually beneficial. The second question we need to ask is: how, in fact, has disgust been coopted? Kelly (2011) discusses this issue at length, but I'll just mention a few representative examples. We know that people use disgust to regulate food and other substances that enter the body (see Nemeroff and Rozin 1992 on moral disgust at failures to keep kosher, Fessler and Navarrete 2003 on vegetarians being disgusted by meat, and Nichols 2002 on disgust as poor table manners; additionally, see Rozin et al. 1999 on disgust at the use of cigarettes, alcohol, and drugs). Likewise, people use disgust used to regulate sexual practices, thereby policing both what enters the body and that with which the body comes into contact (see Lieberman et al. 2003 on incest and Inbar et al. 2009a on homosexual sex). And then there are cases in which there is no straightforward connection between what's disgusting simpliciter and what's morally disgusting-as, for example, when disgust is marshalled against those who lack the "correct" political commitments (see Inbar et al. 2009).9 Having considered these two questions, we can begin thinking more clearly about the ends that moral disgust could serve. Based on the mechanisms behind disgust (aversion, expulsion, contagion, and signaling), the nature of the moral emotions, and the actual use of disgust for moral purposes, William Miller's hypothesis is quite promising: Disgust [...] is especially useful and necessary as a builder of moral and social community. It performs this function obviously 9 We might worry that the term "disgust" is being used loosely in these studies, reporting mere disapproval rather than revulsion per se. Gert (2015) raises this issue in a forceful way. Chapman and Anderson (2013) make the case for the seeing moral disgust as disgust, but obviously don't address Gert's arguments. I set aside these worries here. 13 by helping define and locate the boundary separating our group from their group, purity from pollution, the violable from the inviolable. It does so also as a consequence of its capacity for being readily experienced vicariously. [...] Disgust and indignation unite the world of impartial spectators into a moral community, as cosharers of the same sentiments, as guardians of propriety and purity (1997: 194-195). On this view, moral disgust draws ingroup / outgroup boundaries by enforcing norms that are connected to group identity, as well as enforcing especially important social norms, since failure to comply leaves one's status as an insider in question. This fits with the dietary norms insofar as those are connected to specific identities: conservative Jew; vegetarian; "civilized person." Likewise, it fits with the sexual norms, at least insofar as we value certain family structures. (This isn't to say that these norms are justified; it's just to say that, in fact, some people value certain family structures that have no room for homosexual relationships, among others.) It also fits neatly with marshalling disgust against contrary political views, insofar as those represent alternate visions of how a society ought to be arranged. And finally, it fits with some of the research that led the skeptics to be skeptics: namely, that disgust can be involved in dehumanizing outgroup members (see, e.g., Harris and Fiske 2006 and Buckels and Trapnell 2013). 3.2 Disgust as Heuristic Recall the disgust advocate's position: sometimes, we are justified in believing that actions are wrong based on their being disgusting. Can we use the material from the last section to offer a theory of moral disgust that supports the disgust advocate? I think so. I propose that we understand moral disgust as a moral heuristic.10 More precisely, I propose that we understand moral disgust as a trigger for the subconscious use of a particular rule: If x is disgusting, and we wouldn't do x, then x is morally wrong. The descriptive claim here is this. When people experience disgust and it's reasonable to attribute to them a belief to the effect that we-wouldn't-do-x, then they will usually judge that x is morally wrong. The normative claim is that, 10 This view is inspired by Sunstein (2005). 14 sometimes, people are justified in believing that x is wrong on this basis. Let's call this the heuristic view. A few clarifications are in order. First, "we wouldn't do x"-which I'll call "the subjunctive clause"-isn't equivalent to "we judge that x is morallywrong." The point is that the action is something that, in fact, we don't think we'd do-where the "we" includes the members of the relevant community. The subjective clause says nothing about why we wouldn't do x, and the silence is intentional. Heuristics needn't explain why they're reliable when they are, and their users needn't be able to explain why the heuristic works when it does. Consider the heuristic: If the listener's arms are crossed, then the listener is closed to what I'm saying. People use such heuristics in various circumstances, but they don't necessarily realize that they're using them, nor will they necessarily be able to explain why, for example, there should be any connection between having crossed-arms and being closed to what's being said. But that's not a problem. When an individual uses a heuristic, she needn't be able to provide reasons for her belief in order to form a justified belief-at least if she has no defeaters for that belief.11 Second, the heuristic view doesn't imply that, if we wouldn't do x, then x is morally wrong. There is no suppressed assumption to the effect that wewouldn't-do-x, all on its own, is a guide to wrongness. Instead, the idea is that disgust plus satisfaction of the subjunctive clause-disgust plus we-wouldn't-dox-is a guide to wrongness. Third, the claim isn't that disgust plus we-wouldn't-do-x is a perfect guide to wrongness. We are, after all, in the realm of heuristics, which need only be good enough in the contexts of ordinary use for ordinary use. It would, for example, be silly to complain that the gaze heuristic-which helps us understand how people catch pop flies (they fix their eyes on the ball and run at a pace that keeps the angle constant)-is no good at helping us catch bullets. Fourth, the subjunctive clause has to be relativized to an ingroup, and both the "in" and "group" parts are important here. The "group" part matters because there are some things that are disgusting-like cleaning toilets or handling garbage-that I might not do, but that people in my community do regularly. As long as we consider those persons members of our community, there is no negative moral evaluation. (Unfortunately, we don't always consider them to be 11 This provides the beginning of a story about what goes wrong in cases of moral dumbfounding (see Haidt 2001), where individuals don't know how to justify their revulsion, but remain unwilling to abandon their moral position. In short, it seems that those people are unwilling to consider defeaters. 15 full members-or, perhaps, not members of the community with which we most closely identify.) The "in" part matters because moral disgust is a guide to wrongness relative to my community's standards.12 3.3 The Heuristic View at Work To see how the heuristic view works, consider Leon Kass's famous appeal to revulsion at the prospect of human cloning, which is often mentioned by disgust's critics: We are repelled by the prospect of cloning human beings not because of the strangeness or novelty of the undertaking, but because we intuit and feel, immediately and without argument, the violation of things that we rightfully hold dear. Repugnance, here as elsewhere, revolts against the excesses of human willfulness, warning us not to transgress what is unspeakably profound. Indeed, in this age in which everything is held to be permissible so long as it is freely done, in which our given human nature no longer commands respect, in which our bodies are regarded as mere instruments of our autonomous rational wills, repugnance may be the only voice left that speaks up to defend the central core of our humanity. Shallow are the souls that have forgotten how to shudder (1997: 20). Obviously, Kass is repulsed by the prospect of cloning. His comments about "the excesses of human willfulness" make it pretty plausible that he's committed to something like "we wouldn't clone." Accordingly, he condemns it. As Kass makes clear in the rest of the essay, his basic concern is that "this age" is open to altering what he regards as sacred: the meaning of the (heterosexual, penis-in-vagina) sex act, the nuclear family (defined as one man, one woman, and their naturally-conceived or adopted children), and so forth. Kass tries to articulate why we might keep these things as he would have them kept, and his critics tend to regard his arguments as poor-just one slippery slope after another. Indeed, Kass realizes that the people of "this age" don't share the 12 Sometimes, of course, it's hard to tell these two aspects apart. As a reviewer pointed out to me, there are lots of things that I find repugnant and wouldn't do-such as tell racist jokes-that are common in my part of the world. Does the fact that people near me tell such jokes show that we aren't members of the same moral community? Alternately, does it show that I'm wrong about the community standards-or that the joke tellers are? Does it show something else entirely? I don't have neat answers to these questions, but perhaps they locate complexity in the right places: namely, the nature of moral communities, and our complex relationships with them. 16 conservative ideals that structure the community of which Kass counts himself a member. So, while he tries to argue without presupposing those commitments, he ultimately has to play up repugnance. As the heuristic view suggests, disgust alone gets no traction without the we-wouldn't-do-x reaction. It doesn't lead to moral condemnation if it can't draw on existing community norms. (And, of course, nothing I've said implies that Kass's conservative commitments are justified, and so nothing I've said implies that he is justified in believing that cloning is wrong based on cloning's repugnance.) So the heuristic view can explain both Kass's moral judgment and the breakdown in communication between Kass and his critics. But can it help us preserve the disgust advocate's position? After all, one of Kass's critics might take this case as supporting disgust skepticism. Didn't disgust lead Kass astray? Yes, but not in a way that tells against the disgust advocate's position. On the heuristic view, moral disgust tells you that community-defining norms are being violated, not whether those norms are ultimately worthy of respect. In the end, whether disgust ends up being a good guide to moral wrongness depends on whether your community has reasons-or whether reasons could be generated- in favor of those norms. Sometimes those reasons are indeed available. So if your community norms can be justified, then you needn't have a defeater for your use of disgust, which means that it can provide justification. Likewise, if the arguments for your community norms are in shambles, then disgust is useless-at least as soon as you realize that those arguments are in shambles, and that no better ones are in the offing. So the heuristic view allows us to say that disgust is a very poor guide to wrongdoing in some communities-e.g. within conservative religious groups when directed toward certain sexual practices-and a much better guide in others-e.g., within pluralistic democracies when directed toward torture.13 Granted, it isn't always transparent to the disgusted person whether there are good reasons in favor of her community-defining norms. However, it's perfectly reasonable to assume that there are such reasons in the absence of defeaters.14 There is a division of cognitive labor too, so we ought to presume that others have thought things through more deeply than we have. It takes some questioning before it's appropriate to conclude that there are no satisfying reasons in favor our community's standards, since it would be hasty to infer from one 13 There are a few papers that defend the place of disgust in a liberal society; these papers generally respond to Nussbaum's arguments for the opposite view. (See, e.g., her 2004.) I see these authors as making a point much like the one I'm making in this paragraph, though without the theoretical framework that I've developed to make sense of it. See, e.g., Kahan (1999), Arneson (2006), Clark and Fessler (forthcoming). 14 As I hinted in the last paragraph, I don't think that being unable to provide cogent arguments for those norms on the spot constitutes a defeater-contra the apparent assumption of Haidt's (2001) work on dumbfounding. 17 poor argument that there isn't a better one in the wings. So, you don't need to be able to defend your community's norms on the spot to be justified. Still, the absence of evidence will eventually become the evidence of absence. Importantly, then, the heuristic view helps us understand when we should and shouldn't trust disgust. We shouldn't throw it out entirely based one failure- or even a string of failures. If disgust is defeated often enough in a particular domain, then disgust does lose all its evidential value in that domain. Nevertheless, that's compatible with it having value in others. More interestingly, it's compatible with disgust's having evidential value in other domains even when we have a hard time coming up with independent arguments that vindicate our revulsion. To see what I have in mind, let's imagine Steve. Steve is repulsed by gay sex, wouldn't engage it in himself, and would be repulsed by others were he to find out that they enjoy it. Initially, the heuristic view says that he's justified in believing that gay sex is wrong. However, Steve soon realizes that his community has no good argument for the conclusion that gay sex is morally wrong, and he has no better argument to offer. So, he learns not to condemn it based on its "yuck factor." Now, disgust offers him no evidence that gay sex is wrong. Steve has similar reactions to, and makes similar discoveries concerning, other sexual acts: certain types of pornography, open relationships, BDSM, and so on. In the early cases, the heuristic view says that he was justified in believing that the practice was wrong based on his disgust, but he loses that justification after discovering that his judgment can't be backed by independent moral considerations. As he confronts more cases, his justification weakens. In due course, though, Steve confronts a novel sexual practice-say, people who like to have sex while dressed as animals-and isn't at all justified in condemning this fetish based on its repulsiveness. At this point, he shouldn't trust disgust in the sexual domain; its repeated failures constitute a persistent defeater. But suppose that Steve is also disgusted by dog fighting rings. Here, it's easy to back up his disgust. Suppose that he's also repulsed by standard practices in factory farms. Again, he finds plenty of reasons in favor of his judgment. Indeed, whenever Steve is disgusted by our treatment of animals, he finds it easy to provide independent reasons in favor of his judgment. At some point, though, he considers stories about slaughter practices in the best family farms, where animals lead fairly nice lives, suffering only a short while when killed. Steve still finds himself disgusted, but isn't sure how to justify his negative evaluation. (Suppose he isn't convinced that animals have rights, so he can't rely on that framework to settle the question.) Here, I think disgust's positive track record suggests that Steve can keep trusting his disgust, at least for a time, even without 18 being able to offer a reason, and even if no one in his community has one either.15 Where our treatment of animals is concerned, disgust looks to be a good heuristic, so there is a strong presumption in its favor compared to other domains. (Of course, consistently being unable to tell any plausible story will count weaken Steve's justification, and eventually eliminate it entirely.)16 All of this makes it easier to appreciate Kass's disgust-based rejection of cloning, even if we aren't impressed by it. Suppose that there were good arguments for Kass's conservative ideals. Then, even if Kass and other conservatives found it difficult to explain why, exactly, cloning was morally wrong, it would have been true that his disgust was a good guide to wrongness in the past. The heuristic view says that, in such circumstances, Kass would be justified in condemning cloning based on its repugnance.17 This helps us to explain why Kass thought he was justified in condemning cloning, even if he wasn't. Surely he takes there to be good reasons to endorse his community's norms, and so he's willing to trust disgust even when it's hard to make out the connection between those norms and cloning. Of course, insofar as we're skeptical of his ideals, we're also going to be inclined to deny that disgust has a great track record in the relevant domain-namely, new technology. But we needn't endorse disgust skepticism to conclude that, at least where cloning is concerned, there is no wisdom in repugnance. 4 Concluding Remarks I suspect that the heuristic view is well-suited to dodging the criticisms of disgust skeptics. First, disgust does admit false positives, but we can learn not to trust the disgust heuristic in those domains. Second, disgust can be used to dehumanize, which probably flows from the way it draws a line between the in-group and outgroup. But my claim is just that disgust is a heuristic, not that it carves the moral universe at its joints. We know full well that we shouldn't dehumanize others, so we can correct for this tendency. Third, it's true that disgust's evolutionary history doesn't provide reason to think that it's sensitive to morally-relevant properties, but it can justify belief without being sensitive to such properties. Finally, there is indeed immense variation in what we find disgusting, but that is no more a 15 This particular example is complicated by the fact that Steve may well find himself at odds with his community by being skeptical about "humane" slaughter. By the lights of the heuristic view, this may mean that Steve is discovering that he was wrong about the moral community of which he's a member. 16 For more on the heuristic view and animals, see Fischer (2014). 17 As with Steve, this justification would be contingent on eventually being able to explain why cloning is wrong, and would weaken the longer it took to provide an explanation. 19 problem than that there is immense variation in what we take to be wrong. The problem of moral disagreement is real, but it is not a special problem for disgust. Given all this, the heuristic view of disgust seems more promising than the social contagion view. According to the heuristic view, moral disgust can provide evidence that community-defining and especially important norms are being violated. And inasmuch as those norms have good moral reasons behind them, disgust is a good moral heuristic. 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