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Agents, Impartiality, and the Priority of Claims over Duties: Diagnosing Why Thomson Still Gets the Trolley Problem Wrong by Appeal to the “Mechanics of Claims” *

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Judith Jarvis Thomson recently argued that it is impermissible for a bystander to turn a runaway trolley from five onto one. But she also argues that a trolley driver is required to do just that. We believe that her argument is flawed in three important ways. She fails to give proper weight to (a) an agent¹s claims not to be required to act in ways he does not want to, (b) impartiality in the weighing of competing patient-claims, and (c) the role of patient-claims in determining agent-duties. All three of these failures can be understood in terms of what we call the Mechanics of Claims, an approach we develop for identifying and balancing competing claims in determining rights. Using that framework, one can see both why Thomson’s most recent argument is mistaken, and how to think more clearly about deontological choices generally.

1. fn53* We would like to thank John David Evans, Dick Fallon, Mattias Kumm, Jeff McMahan, Jerome Segal, Rachel Somerville, Alan Strudler, and Leif Weinar for their helpful discussions and edits.
2. fn11 ‘Killing, Letting Die, and the Trolley Problem,’ The Monist 59 (1976), pp. 204-17.
3. fn22 For just one example of the vast empirical literature supporting this claim, see F. Cushman, L. Young & M.D. Hauser, ‘The Role of Reasoning and Intuition in Moral Judgments: Testing Three Principles of Harm,’ Psychological Science 17 (2006), pp. 1082-1089.
4. fn33 ‘Killing, Letting Die, and the Trolley Problem.’
5. fn44 ‘The Trolley Problem’, in Rights, Restitution, and Risk (Cambridge, MA: Harvard University Press, 1986), p. 108.
6. fn55 ‘The Trolley Problem’, in The Realm of Rights (Cambridge, MA: Harvard University Press, 1990).
7. fn66 ‘Turning the Trolley’, Philosophy and Public Affairs 36 (2008), pp. 359-74.
8. fn77 We are aware of two other critical responses to Thomson’s argument: William FitzPatrick, ‘Thomson’s Turnabout on the Trolley,’ Analysis 69 (2009), pp. 636-643; and Robert Shaver, ‘Thomson’s Trolley Switch,’ Journal of Ethics and Social Philosophy August 2011 ( The differences between our criticisms and theirs will be noted below, after we have laid out more of Thomson’s argument.
9. fn88 Jeff McMahan, ‘The Just Distribution of Harm Between Combatants and Noncombatants,’ Philosophy and Public Affairs 38 (2010), pp. 342-379.
10. fn99 One of us, Alec Walen, does defend this solution in ‘Transcending the Means Principle; How the Restricting Claims Principle Illuminates the Moral Significance of Being Used as a Means,’ (available at  = 1372416).
11. fn1010 ‘Turning the Trolley,’ p. 364.
12. fn1111 Id, p. 365.
13. fn1212 Id.
14. fn1313 Id, p. 366 (emphasis added).
15. fn1414 Id, p. 367.
16. fn1515 Id.
17. fn1616 See id, p. 372.
18. fn1717 See, for example, ‘Physician-Assisted Suicide: Two Arguments,’ Ethics 109 (1999), pp. 497-518.
19. fn1818 Walen argues that there is nothing fundamentally morally problematic in using another merely as a means, while also arguing that the distinction between using someone merely as a means and harming someone as a side-effect tracks a sound moral principle well enough to be a morally useful shorthand in cases like this. ‘Transcending the Means Principle’. He also argues that the relevant moral distinction applies to property as well as to bodies. Id. See also Jonathan Quong, ‘Killing in Self-Defense,’ Ethics 119 (2009), pp. 526-530.
20. fn1919 Wesley Hohfeld introduced his analysis of rights into four pairs (two first-order; two second-order) of “jural opposites” and four pairs of “jural correlatives,” in two papers: ‘Some Fundamental Legal Conceptions as Applied in Judicial Reasoning,’ Yale Law Journal 23 (1913), pp. 16 - 59; and ‘Fundamental Legal Conceptions as Applied in Judicial Reasoning,’ Yale Law Journal 26 (1917), pp. 710 - 770.
21. fn2020 This account can be contrasted with one recently offered by FitzPatrick in ‘Thomson’s Turnabout on the Trolley,’ pp. 641-642. According to that account, you are obliged to turn the trolley, but you should be excused for any failure to do so because we expect people to be averse to killing. This account would implausibly support using coercive pressure to get you to overcome your aversion and turn the trolley. Moreover, it fails to recognize the significance of agents not being merely tools for promoting the general welfare.
22. fn2121 Again, Walen defends this assumption in ‘Transcending the Means Principle’.
23. fn2222 In certain roles, such as that of a parent, you have property-like claims over others, such as your children. These claims are property-like not in treating their subjects as commodities, but in giving you the right to exclude third parties from interfering with the decisions you make in fulfilling your role. You also have special responsibilities to those people, reflecting their special claims on you.
24. fn2323 Frances Kamm, Morality, Mortality Volume I: Death and Whom to Save From It (Ch. 8) pp. 144-165 (Oxford: Oxford University Press, 1993).
25. fn2424 For example, Thomson introduced the “Loop Trolley” variation on Trolley Switch in ‘The Trolley Problem’ to show that one cannot appeal to the thought that the massive man would be used merely as a means to solve the Trolley Problem. Walen explicitly addresses this argument in ‘Transcending the Means Principle’.
26. fn2525 This factor approach is similar to the contextualism emphasized by those who favor “specificationism.” See, e.g., John Oberdiek, ‘Specifying Rights out of Necessity,’ Oxford Journal of Legal Studies 28 (2008), pp. 127-146; and Russ Shafer-Landau, ‘Specifying Absolute Rights,’ Arizona Law Review 37 (1995), pp. 209-225. The primary virtue of a factor approach is that it allows one to have a systematic understanding of how and why Hohfeldian rights arise.
27. fn2626 We know of no one who puts the three principles in exactly that way, but they are recognized in some form by a great many liberal writers. John Rawls, for example, uses the notion of primary goods to capture the idea that human welfare matters; his rejecting utilitarianism for failing to “take seriously the distinction between persons” (A Theory of Justice (New York: Oxford University Press, 1972), p. 27) reflects the thought that each should be free to lead her own life; and his two principles of justice reflect the fundamentally equal status of all as rights-bearers.
28. fn2727 Our response to Thomson is different from that offered by FitzPatrick in ‘Thomson’s Turnabout on the Trolley’ in three important ways. First, he shows no sympathy with Thomson’s intuition in TSB3; we do. Second, his account of where she goes wrong with TSB3 appeals to an overly thin version of the Golden Rule; we appeal to a thicker conception of impartiality. Third, as mentioned above, he suggests that allowing the larger number to die in TSB cases might be impermissible but blameless; we think it is clearly permissible. Our response also differs from Shaver’s criticism in ‘Thomson’s Trolley Switch,’ because his argument is focused on rejecting Thomson’s claim that you may not turn the trolley onto the side-track man in TSB3; we think Thomson’s claim may well be correct.
29. fn2828 ‘Turning the Trolley,’ p. 365.
30. fn2929 Id, p. 366.
31. fn3030 Id, p. 367.
32. fn3131 ‘Turning the Trolley,’ p. 365. She captures this in her “Third Principle: A must not kill B to save five if he can instead kill himself to save five.” Id.
33. fn3232 Thomson insists that the bystander may not flip a coin to determine whether he or the right-track man gets hit. ‘Turning the Trolley,’ p. 371. We explain why we think she is wrong about that below, when discussing the first interpretation of impartiality as applied toTSB3.
34. fn3333 Empirical research indicates that over 40% of people disagree with Thomson on TSB3; they think the bystander should turn the trolley onto the right-track man. See Bryce Huebner and Mark Hauser, ‘Moral Judgments About Altruistic Self-Sacrifice; When Philosophical and Folk Intuitions Clash,’ Philosophical Psychology24 (2011): 73-94.
35. fn3434 ‘Turning the Trolley,’ p. 364.
36. fn3535 If the situation were asymmetrical, so that he could turn it either to the left where it would hit two, or to the right where it would hit him, he would have to allow it to hit him. If he finds that choice unacceptable, then he can choose the alternative of allowing it to hit the five.
37. fn3636 This hypothetical presents a forced choice among lives and raises the issue of whether the individual responsible for there being such a choice should be the one “chosen” to sacrifice his life. As Seth Lazar has argued (‘Responsibility, Risk, and Killing in Self-Defense,’ Ethics 119 (2009) 699-728; 701, 714-715), the most plausible position is that only an individual who is culpably responsible for the forced choice should bear its burden, not someone who is innocently responsible. (The appeal of the latter view, Lazar observes, comes from its greater ease of application in actual forced choices, particularly in “the fog of war,” where the culpability of individual agents usually cannot be assessed.) In our case, you are not only innocent in creating the forced choice between you and your fellow passenger, you are arguably justified in doing so. If you should not forfeit your right to life for innocently creating such a situation, a fortiori you should not forfeit your right to life for doing so justifiably.
38. fn3837 This is not to deny that one might think poorly of the agent who was willing to sacrifice another but not himself in different versions of TSB2. But Thomson should be the first one to recognize that the fact that we think poorly of an agent does not make his action impermissible. Robert Shaver argues in ‘Thomson’s Trolley Switch’ that Thomson appears to rely on a mistaken inference from character to permissibility in asserting that a bystander unwilling to turn the trolley onto himself “cannot decently regard himself as entitled” to turn it on to someone else. Because of her position on intention and permissibility – see ‘Physician Assisted Suicide,’ pp. 514-516 – we doubt that she is actually making this inference, but her language certainly encourages the reader to make it.
39. fn3938 ‘Turning the Trolley,’ p. 372.
40. fn4039 An anonymous commentator on an earlier draft made this argument.
41. fn4140 Michael Costa, ‘Another Trip on the Trolley,’ The Southern Journal of Philosophy 25 (1987), p. 464, claims that the Doctrine of Double Effect (DDE) distinguishes between “redirecting an existing source of harm and creating a new one. One who does the latter is originating harm. This is a prima facie evil.” If this is a sound interpretation of the DDE, it gives the distinction a pedigree. But it still seems to us a distinction without a moral difference.
42. fn4241 See ‘Killing, Letting Die, and the Trolley Problem.’
43. fn4342 It is not clear whether Thomson would be willing to make this distinction, given her denial that intentions are relevant to permissibility, and her denial that the distinction can be defended in terms of rights (see The Realm of Rights, p. 179 n. 2). But a defender ofThomson’s current view of the trolley problem, unencumbered by her other commitments, might well raise it.
44. fn4443 The lion case was discussed by Frances Kamm, ‘Harming Some to Save Others,’ Philosophical Studies 57 (1989), pp. 227-260. See also Richard Brook, ‘Agency and Morality,’ The Journal of Philosophy 88 (1991), pp. 190-212.
45. fn4544 The cases are different insofar as the agent in the lion’s den case would have to use the sixth person merely as a means of saving the first five, while the driver of the trolley in TSD2 would harm the side-track man as a side-effect of saving the five. But that difference should not distract from the main point, which is that in neither TSD2 nor the lion’s den case does the agent face a present choice between killing five and killing one.
46. fn10145 Thomson might want to argue that she can accommodate the significance of the temporal dimension within a duty perspective. She could say that once you unleash a threat on another, you acquire a duty to try to mitigate the harm, a duty that could require you to sacrifice yourself but that is weaker than the duty not to cause harm and that would therefore neither require nor permit you to violate your duty not to kill another innocent person. But then the driver would be no more permitted to turn the trolley onto the side-track man in TSD2 than the bystander in TSB2. Thus this attempt to avoid our objection would necessarily undermine her own account of what is distinctive about the duty perspective. This problem is of a piece with the point we make in the text three paragraphs below.
47. fn4646 ‘Killing, Letting Die, and the Trolley Problem,’ p. 207.
48. fn4747 We are grateful to Jeff McMahan, who reviewed our paper for this journal, and raised this and the next argument that we consider.
49. fn4848 ‘Turning the Trolley,’ p. 369.
50. fn4949 Thomson is actually agnostic about the source of duties, saying “I know if no thoroughly convincing account of [the] source [of the difference in the weight of positive and negative duties].” ‘Turning the Trolley,’ p. 372.
51. fn5050 Would a driver have to turn into a wall in order to avoid killing others, as Thomson contends? ‘Turning the Trolley,’ p. 370. That surely depends on what level of responsibility the driver assumed. It could be imagined that he assumes such responsibility in virtue of taking the job of driving the trolley. It could also be argued that one takes such responsibility if one takes one’s car out on a drive. But a passenger who gets up to try to steer a trolley after the driver drops dead has not assumed such responsibility, even if he steers long enough to say that he will kill the five if he does not turn the trolley away from them.
52. fn5151 ‘The Just Distribution of Harm Between Combatants and Noncombatants,’ p. 369.
53. fn5252 Of course the combatant would introduce new threats, not divert an existing threat. But as we noted in the text above, there is no reason to give that distinction any moral weight.

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Affiliations: 1: Department of Philosophy, College Avenue Campus, New Brunswick, NJ 08901, USA & Rutgers University School of Law – Camden, 217 North 5th Street, Camden, NJ 08102, USA, ; 2: Center for Ethics, 917 Belfer Hall, 2495 Amsterdam Avenue, New York, NY 10033, USA,


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