I want to suggest a few ways that Stanford's proposal can be extended by focusing on an emotion that may play a role in externalization – namely, disgust (cf. Nichols Reference Nichols2014, pp. 736–40). The psychological profile of disgust includes a sensitivity to contamination via contact, similarity, or association, and that results in avoidance of contaminated objects (Rozin & Fallon Reference Rozin and Fallon1987). This suggests that disgust evolved for the avoidance of poisons, parasites, and pathogens (cf. Kelly Reference Kelly2011, pp. 52–59). Moreover, disgust appears to play an important role in human moral psychology (e.g., Rozin & Haidt Reference Rozin and Haidt2013). For example, involuntary effects on facial muscles associated with distaste and disgust at contaminants have also been observed in reaction to perceptions of unfair treatment (Chapman et al. Reference Chapman, Kim, Susskind and Anderson2009).
Given the functional role of disgust and its penetration into the social and moral domain, it is plausible that – as Kelly has suggested – the process of gene-culture co-evolution co-opted disgust to motivate norm compliance and enforcement (Kelly Reference Kelly2011, pp. 116–22). On this view, if one comes to feel that certain acts are disgusting (e.g., acts that violate certain kinds of norms), one will avoid committing such acts oneself and one will avoid those who commit such acts (because they are contaminated thereby). Importantly for my purposes, one may also think that others have reason to avoid such acts (since they would be contaminated thereby). If this is an accurate picture of disgust, then disgust appears to offer one way in which a person can come to experience “moral motivation as externally imposed on both ourselves and others simultaneously” (Stanford target article, sect. 5, para. 7). For instance, even if there is salient disagreement about what is disgusting, disgust naturally lends itself to the thought that others should not contaminate themselves via contact with what I deem disgusting. Thus, insofar as a moral norm becomes linked to disgust, disgust will provide an immediate route to externalization. (Though it is unlikely that this will be a good explanation for the externalization of all norms, since it is unlikely that disgust is linked in these ways to the entire range of moral norms.)
This hypothesis suggests two extensions of Stanford's proposal. First, although Stanford highlights the value of externalization for stabilizing cooperation norms against the competing interests of cooperators and free riders, externalization also has value for solving coordination problems where interests of different groups coincide. To see this, consider part of Kelly's (Reference Kelly2011, pp. 123–25) co-opt hypothesis: that disgust was co-opted to implement tribal instincts that function to preserve boundaries between ethnic groups. Disgust could accomplish this by motivating one not to interact with members of other groups, in part because they violate the disgust-linked norms of one's group. If so, then disgust may be a mechanism for what Stanford calls “correlated interaction under plasticity” (sect. 5, para. 8). Howsoever the norms of two groups might diverge over time, disgust will tend to motivate or cause correlated interactions within groups but not between them. However, this suggestion actually applies to Stanford's proposal in a way quite unlike the one he discusses. For example, if two cultural groups have different moral norms (as is likely to be the case even for closely related cultural groups), intergroup interactions will not be as profitable for members of either group, because expectations regarding the interaction are more likely to diverge (McElreath et al. Reference McElreath, Boyd and Richerson2003). Thus, members of each group have a shared interest in avoiding interactions with members of the opposite group. In this case, externalization of moral norms – realized in part by mutual disgust – can result in a tendency to minimize interactions with different groups, and this tendency may benefit both groups.
Second, Stanford points out that externalization can explain why hypocrisy is considered a moral violation above and beyond the wrongness of acts committed (though also condemned) by the hypocrite. However, in light of the above hypothesis, his proposal may also be able to explain why people tend to over-comply with norms to the point of disassociating from actions that merely appear to violate the norm. As Stanford suggests, externalization likely led to a feedback loop in which cognitive and linguistic abilities became more useful specifically for purposes of moral advertisement. The increased importance of moral advertisement makes it all the more crucial to prevent misleading advertisements like innocently giving the appearance of evil. Thus, one would predict that if Stanford's externalization story is correct, then being motivated to comply with moral norms and avoid those who do not will also be coupled with a tendency to avoid the appearance of violating a moral norm. For instance, moral vegetarians tend to avoid eating meat that would otherwise be discarded (e.g., their roommate's leftovers), even when eating it would not spare any animals from harm. Disgust is one sort of mechanism that might explain this behavior. Because the contamination sensitivity of disgust operates via contact, similarity, and association, acts that merely resemble or are associated with disgust-linked moral violations (e.g., eating meat that has been “tainted” by the cruel practices of factory farms) will also tend to be avoided. Moreover, because disgust is linked to evaluations of bad character (Giner-Sorolla & Chapman Reference Giner-Sorolla and Chapman2017), it may also motivate avoidance of actions that are merely associated with bad character.
Although avoiding the appearance of evil may seem to require metarepresentation, disgust provides a mechanism for implementing such avoidance without having to think about one's actions from another perspective. For example, moral vegetarians clearly have an interest in avoiding the appearance of contributing to animal suffering (e.g., by eating the leftovers from a catered event). Nevertheless, if they are disgusted by meat consumption, they will be motivated to avoid eating the meat without considering what others might think of them. Thus, disgust provides a simple and economical way of implementing externalization of norms in some moral domains and hence may have been an early and influential driver of externalization.
I want to suggest a few ways that Stanford's proposal can be extended by focusing on an emotion that may play a role in externalization – namely, disgust (cf. Nichols Reference Nichols2014, pp. 736–40). The psychological profile of disgust includes a sensitivity to contamination via contact, similarity, or association, and that results in avoidance of contaminated objects (Rozin & Fallon Reference Rozin and Fallon1987). This suggests that disgust evolved for the avoidance of poisons, parasites, and pathogens (cf. Kelly Reference Kelly2011, pp. 52–59). Moreover, disgust appears to play an important role in human moral psychology (e.g., Rozin & Haidt Reference Rozin and Haidt2013). For example, involuntary effects on facial muscles associated with distaste and disgust at contaminants have also been observed in reaction to perceptions of unfair treatment (Chapman et al. Reference Chapman, Kim, Susskind and Anderson2009).
Given the functional role of disgust and its penetration into the social and moral domain, it is plausible that – as Kelly has suggested – the process of gene-culture co-evolution co-opted disgust to motivate norm compliance and enforcement (Kelly Reference Kelly2011, pp. 116–22). On this view, if one comes to feel that certain acts are disgusting (e.g., acts that violate certain kinds of norms), one will avoid committing such acts oneself and one will avoid those who commit such acts (because they are contaminated thereby). Importantly for my purposes, one may also think that others have reason to avoid such acts (since they would be contaminated thereby). If this is an accurate picture of disgust, then disgust appears to offer one way in which a person can come to experience “moral motivation as externally imposed on both ourselves and others simultaneously” (Stanford target article, sect. 5, para. 7). For instance, even if there is salient disagreement about what is disgusting, disgust naturally lends itself to the thought that others should not contaminate themselves via contact with what I deem disgusting. Thus, insofar as a moral norm becomes linked to disgust, disgust will provide an immediate route to externalization. (Though it is unlikely that this will be a good explanation for the externalization of all norms, since it is unlikely that disgust is linked in these ways to the entire range of moral norms.)
This hypothesis suggests two extensions of Stanford's proposal. First, although Stanford highlights the value of externalization for stabilizing cooperation norms against the competing interests of cooperators and free riders, externalization also has value for solving coordination problems where interests of different groups coincide. To see this, consider part of Kelly's (Reference Kelly2011, pp. 123–25) co-opt hypothesis: that disgust was co-opted to implement tribal instincts that function to preserve boundaries between ethnic groups. Disgust could accomplish this by motivating one not to interact with members of other groups, in part because they violate the disgust-linked norms of one's group. If so, then disgust may be a mechanism for what Stanford calls “correlated interaction under plasticity” (sect. 5, para. 8). Howsoever the norms of two groups might diverge over time, disgust will tend to motivate or cause correlated interactions within groups but not between them. However, this suggestion actually applies to Stanford's proposal in a way quite unlike the one he discusses. For example, if two cultural groups have different moral norms (as is likely to be the case even for closely related cultural groups), intergroup interactions will not be as profitable for members of either group, because expectations regarding the interaction are more likely to diverge (McElreath et al. Reference McElreath, Boyd and Richerson2003). Thus, members of each group have a shared interest in avoiding interactions with members of the opposite group. In this case, externalization of moral norms – realized in part by mutual disgust – can result in a tendency to minimize interactions with different groups, and this tendency may benefit both groups.
Second, Stanford points out that externalization can explain why hypocrisy is considered a moral violation above and beyond the wrongness of acts committed (though also condemned) by the hypocrite. However, in light of the above hypothesis, his proposal may also be able to explain why people tend to over-comply with norms to the point of disassociating from actions that merely appear to violate the norm. As Stanford suggests, externalization likely led to a feedback loop in which cognitive and linguistic abilities became more useful specifically for purposes of moral advertisement. The increased importance of moral advertisement makes it all the more crucial to prevent misleading advertisements like innocently giving the appearance of evil. Thus, one would predict that if Stanford's externalization story is correct, then being motivated to comply with moral norms and avoid those who do not will also be coupled with a tendency to avoid the appearance of violating a moral norm. For instance, moral vegetarians tend to avoid eating meat that would otherwise be discarded (e.g., their roommate's leftovers), even when eating it would not spare any animals from harm. Disgust is one sort of mechanism that might explain this behavior. Because the contamination sensitivity of disgust operates via contact, similarity, and association, acts that merely resemble or are associated with disgust-linked moral violations (e.g., eating meat that has been “tainted” by the cruel practices of factory farms) will also tend to be avoided. Moreover, because disgust is linked to evaluations of bad character (Giner-Sorolla & Chapman Reference Giner-Sorolla and Chapman2017), it may also motivate avoidance of actions that are merely associated with bad character.
Although avoiding the appearance of evil may seem to require metarepresentation, disgust provides a mechanism for implementing such avoidance without having to think about one's actions from another perspective. For example, moral vegetarians clearly have an interest in avoiding the appearance of contributing to animal suffering (e.g., by eating the leftovers from a catered event). Nevertheless, if they are disgusted by meat consumption, they will be motivated to avoid eating the meat without considering what others might think of them. Thus, disgust provides a simple and economical way of implementing externalization of norms in some moral domains and hence may have been an early and influential driver of externalization.