Abstract
Based on the results of empirical studies of folk moral judgment, several researchers have claimed that something like the famous Doctrine of Double Effect (DDE) may be a fundamental, albeit unconscious, component of human moral psychology. Proponents of this psychological DDE hypothesis have, however, said surprisingly little about how the distinction at the heart of standard formulations of the principle—the distinction between intended and merely foreseen consequences—might be cognised when we make moral judgments about people’s actions. I first highlight the problem of precisely formulating the distinction between intended and foreseen consequences and its implications for interpreting the empirical data on folk moral judgment. I then distinguish between three different approaches to this problem that have been taken by proponents of the DDE in normative ethics: so-called “closeness” accounts, accounts that employ what has come to be known as a “strict” notion of intention, and Warren Quinn’s recasting of the DDE in terms of the distinction between “direct” and “indirect agency”. I show that when taken as claims about moral psychology, these different accounts entail quite different empirical predictions about what people’s moral judgments should be in particular cases. Based on the current empirical data, I argue that a version of Quinn’s formulation of the DDE is the most empirically plausible, and that adopting such a formulation helps to diffuse much (though not all) of the recent empirical criticism of the DDE hypothesis.
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Notes
The DDE is usually traced back to Aquinas’ discussion of self-defence in Summa Theologica, though contemporary discussions arguably owe more to nineteenth-century formulations (see Connell and Kaczor 2013). Other conditions of the principle typically include a proportionality condition (that the moral benefits brought about by the action outweigh its harmful effects), and the condition that there be no better alternatives (e.g., a way to achieve the good end without causing any harm). Proponents of the principle also tend to emphasise that it should not be taken to be a complete moral theory, but only a component of one. Thus, the verdict of the DDE with respect to a particular act ought not be taken as the last word on the matter.
These studies (especially those reported by Mikhail 2000, 2011) have also found effects corresponding to other components of the DDE, such as proportionality and no better alternative conditions. It should also be noted that the apparent effect of intentions on moral judgment seems hold even in the absence of the use of personal force and direct physical contact, both potentially confounding factors in the standard Footbridge case (Mikhail 2000, 2011; Cushman et al. 2006; Hauser, et al. 2007; Arbarbanell and Hauser 2010; Huebner, et al. 2011). Though the pattern is not entirely uniform (see, e.g., Greene et al. 2009; Greene 2013), most studies find that participants still tend to judge it impermissible to use the large man to stop the trolley from killing the five in “impersonal” versions of the Footbridge case where the agent does not have to push the large man off the bridge or use any personal force to move the large man in front of the trolley (e.g., where the agent instead pushes a button to drop the large man in front of the trolley). Such impersonal versions of this scenario do receive relatively higher permissibility ratings, suggesting that the use of personal force does have an interacting effect with intention (see Greene et al. 2009). Nonetheless, such impersonal versions of the Footbridge case still tend to receive significantly lower permissibility ratings than those for the Switch case.
One criticism of this research concerns the putative artificiality of the trolley-style scenarios that have been used, leading to the worry that the results of these studies may not get at any real underlying psychological principles, but only reflect how people respond to unusual hypothetical cases. However, defenders of this research usually respond that while the scenarios are artificial and unrealistic they do enable us to control for the influence of other factors on moral judgment. Moreover, while concerns have also been raised about the extent to which participants’ judgments may be influenced by various framing and order effects—and hence might be less systematic than they appear (e.g., Schwitzgebel and Cushman 2012; see also Liao et al. 2012; Wiegmann et al. 2012; Wiegmann and Waldmann 2014)—the patterns in moral judgment revealed by these studies do seem to be quite robust and cannot be fully explained away by either the artificiality of the scenarios (one might expect participants’ judgments to be all over the place if that were so) or by framing and order effects. Another concern is that the results usually reveal a significant minority opinion as well as a majority one—for instance, it is almost always the case that a number of participants judge it permissible to push the large man in the Footbridge case. As result, one might be sceptical about using such studies to draw general conclusions about human moral psychology. This is, however, a pervasive phenomenon in psychological research, and thus not especially problematic for making general claims about moral psychology—though, of course, it is important to consider how such diversity in responses is best explained.
There is, it should be noted, a growing literature in experimental philosophy on the folk concept of intention and its connection with moral reasoning. However, most of the focus has been on accounting for the so-called “side effect-effect” (Knobe 2003), in which participants’ explicit judgments of intentionality with respect to the effects of others’ actions sometimes appear to be influenced by their moral evaluation of these effects. In so far as the side effect-effect is a real phenomenon (there is some debate about this), it seems that our judgments of whether an effect of an agent’s action is intended versus merely foreseen may be influenced by moral considerations. However, this does not prevent the causal relationship from going in the other direction as well, and my concern here is with how the intend/foresee distinction may be cognised when it does indeed go in this other direction. Moreover, explicit judgments of intentionality of the sort at issue in the debate over the side effect-effect may potentially come apart from unconscious judgments of intentionality of the sort at issue here, perhaps being the product of quite different cognitive processes.
This is so even in the case of Mikhail’s (2011) otherwise extremely detailed and worked out account of how the DDE (and other candidate moral principles) may feature in moral cognition and be applied by our moral reasoning faculty to particular moral problems. Though Mikhail provides complex structural descriptions of the actions that take place in his trolley scenarios, and attempts to formalise how we unconsciously apply the intend/forsee distinction to mental representations of these act-descriptions via the notions of I-generation and K-generation, the precise nature of this distinction is not spelled out. In particular, the categorisation of particular acts and effects in his scenarios as intended or merely foreseen by the relevant agents is just stipulated. No general principles are given for how we go about determining when an act or effect is intended versus merely foreseen, only an account of what inferences are made when we do in fact make such determinations.
One critic of the DDE hypothesis who does seem to be aware of this issue, but does not discuss it in detail, or take it into account when evaluating his own arguments against the hypothesis, is Joshua Greene, who notes that “there is an interesting psychological problem here: namely to understand the mechanism that parses events in these contexts” (2013, p377; see also Greene et al. 2009, p370). Greene’s own characterisation of the DDE hypothesis comes closest to that I discuss in Section 3.3, but he does not seem to be aware that this is but one of several different ways of formulating the hypothesis.
A similar account of the intend/foresee distinction to (1) can be found in Bratman’s (1999) influential account of intention, according to which an agent intends all those consequences of an action A that the agent is “committed” to bringing about by doing A.
Of course, something that needs to be kept in mind, particularly in what follows, is given that the DDE is not a comprehensive moral doctrine—and thus could only be one component of a folk morality—judgments that deviate from the DDE might just indicate the influence of other moral principles. We should be mindful of this both when trying to distinguish between different versions of the DDE hypothesis, and distinguishing between some version of the DDE hypothesis and rival hypotheses of sort considered later in the paper.
Arguably, tying the DDE to more objective features of the causal structure of the agent’s action, rather than to features of the agent’s psychology, is more consonant with how the doctrine has been understood historically, particularly in the Catholic intellectual tradition (for discussion of the DDE in Catholic moral theology, see Connell and Kaczor 2013).
This does not necessarily mean that the action must therefore be impermissible, only that if it is permissible for the doctor to perform the craniotomy, it is not the DDE that explains why.
As Masek points out, the term “strict” was originally used as a term of abuse by proponents of closeness accounts to refer to accounts of intention that they judged to be too narrow, but it has recently been taken on by proponents of a family of accounts of the DDE that depart from closeness accounts.
Quinn’s discussion of the DDE suggests that the principle specifies when actions are to be regarded as impermissible. However, I agree with Mikhail (2011, p152) that the principle is better understood not as specifying the conditions under which actions are impermissible, but rather conditions under which otherwise impermissible actions may be permissible. Though this may have implications for considering the normative adequacy of Quinn’s formulation (in particular, it would pose difficulties for his Kantian justification for the principle), it does not, I think, have any bearing on my use of his formulation here.
They do not claim that we discount it altogether, but rather that it recedes into the background relative to the harm that will be caused by not acting.
Greene advances a similar hypothesis to that of Waldmann and colleagues. According to his “modular myopia” hypothesis:
We have an automatic system that “inspects” action plans and sounds the alarm [i.e., delivers negative moral evaluations, such as impermissibility judgments] whenever it detects a harmful event in an action plan (e.g., running someone over with a trolley) But […] this action-plan inspector is a relatively simple, “single-channel” system that doesn’t keep track of multiple causal chains… Instead, when it’s presented with an action plan for inspection, it only sees what’s on the primary causal chain. (Greene 2013, p234 [italics in original]).
Hence, according to Greene, the reason that we intuitively distinguish between the moral acceptability of the “action plans” in the Switch and Footbridge cases, is that this automatic system can’t “see” the harm caused to the man on the side track in the former case, since it takes place on a causal chain that branches off from the primary one leading to the saving of the men on the main track, but does “see” the harm caused to the large man in the latter case, since it takes place on the primary causal chain. Like Waldmann and colleagues, Greene argues that the nature of this automatic system leads us to make judgments consistent with the DDE in cases like these—since it cannot “see” harmful side effects—but, in others, our judgments come apart from the DDE. Greene argues that we also have another system that engages in more reflective moral reasoning, which may sometimes conflict with, and occasionally override, the judgments issued by the automatic system. To be clear, Waldmann and colleagues and Greene need not be seen as completely downplaying the role of the agent’s intentions in (automatic) moral judgments. For instance, Greene argues that the automatic system can take intentions into account, such that intentional harms occurring on the primary causal chain are judged to be worse that unintentional ones. Similarly, (as Greene et al. 2009, p369 point out) Waldmann and colleagues’ approach seems to imply that agents are seen as intending to act on victims versus threats, and allows for a possible moral distinction between intentional and accidental harms.
One potential methodological problem here is that Waldmann and colleagues asked participants about whether the agent “should” or “should not act” in the way described in the relevant situation, which is rather different from asking whether the action is “permissible” or “impermissible” (the question asked in most of the experiments that have been claimed to support the DDE hypothesis, such as those of Mikhail). For instance, one can imagine cases in which one might judge that a person’s action is permissible, but also judge that the person should not perform that act. Whether or not this is a significant confound is unclear.
Waldmann and Wiegmann (2010, p5) do actually seem to acknowledge this point about the victim being causally unnecessary, but don’t take it as seriously as they should when it comes to thinking about how the DDE hypothesis ought to be understood.
Another case that seems to pose problems for all three formulations of the DDE hypothesis discussed here is Greene’s Collision Alarm case (unpublished research, reported in Greene 2013, p221–2). Two trolleys are heading down two separate tracks. If nothing is done, the first trolley will kill five workers on the track. However, the second trolley can be redirected onto a side track, where there is one man standing next to an alarm system. If this is done, the trolley will hit and kill the man, but the alarm will be activated, cutting power to the whole network of trolleys, including the first trolley, thus saving the five men. Greene reports a strong majority of participants “approving” of the redirection of the trolley in this case. This would appear to be problematic for a Quinn-style formulation of the DDE hypothesis, since (as Greene describes the case) collision with the man is required to set off the alarm, his involvement is therefore causally necessary for the achievement of the goal
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Acknowledgements
Thanks to two reviewers, William Langenfus, Patrick Mooney, Earl Spurgin, and an audience at John Carroll University for helpful comments on earlier versions of this paper. I also benefited from discussions with participants in the AHRC Culture and the Mind Project.
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Fitzpatrick, S. Distinguishing Between Three Versions of the Doctrine of Double Effect Hypothesis in Moral Psychology. Rev.Phil.Psych. 5, 505–525 (2014). https://doi.org/10.1007/s13164-014-0192-5
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DOI: https://doi.org/10.1007/s13164-014-0192-5