Group Agency and Overdetermination


A morally objectionable outcome can be overdetermined by the actions of multiple individual agents. In such cases, the outcome is the same regardless of what any individual does or does not do. (For a clear example of such a case, imagine the execution of an innocent person by a firing squad.) We argue that, in some of these types of cases, (a) there exists a group agent, a moral agent constituted by individual agents; (b) the group agent is guilty of violating a moral obligation; however, (c) none of the individual agents violate any of their moral obligations. We explicate and defend this view, and consider its applications to problems generated by anthropogenic climate change and electoral politics.

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  1. 1.

    That is, if EU(A throws A’s switch) = -1000*pr(B throws B’s switch) + -1010*pr(B does not throw B’s switch), and EU(A does not throw A’s switch) = -1010*pr(B throws B’s switch) + -20*pr(B does not throw B’s switch), then EU(A throws A’s switch) > EU(A does not throw A’s switch) when pr(B throws B’s switch) > 0.99. And something similar is true for EU(B throws B’s switch).

  2. 2.

    See, for instance, the careful discussion found in Regan (1980).

  3. 3.

    Kagan (2011). In that paper, Kagan considers problems for consequentialism raised by what he calls (following Parfit) “imperceptible difference” cases. These are cases in which “when enough of us perform the act in question, the results will be bad, but for all that, my individual act will make no morally relevant difference at all” (p. 117). Kagan argues, at some length, that such cases are logically impossible given consequentialism (pp. 129–134). To support his view, he shows that one apparent example of such a case turns out not to be such a case after all; from this, he draws the general conclusion that all cases that seem to be imperceptible difference cases cannot be genuine imperceptible difference cases. But in this argument, Kagan mistakenly assumes that all imperceptible difference cases are of the same type as his example. Overdetermination cases (like the case of the two torturers above) meet his criteria for an imperceptible difference case, and are logically possible, so his claim that imperceptible difference cases are logically impossible is false.

  4. 4.

    A “group agent,” in our sense, is fundamentally a moral agent, i.e., a bearer of moral obligations. Therefore, our position is that multiple agents can, as a group, bear moral obligations. This position comes with various commitments, which we will discuss in Section 3. For now, the important point is that, fundamentally, we understand group agents as moral agents.

  5. 5.

    For a useful discussion of OIC, see Vranas (2007).

  6. 6.

    Any defense of MR and RE will depend on what reasons turn out to be, and is thus beyond the scope of this paper. So here we must rely simply on the intuitive appeal of these two principles. For deeper discussion, see Shafer-Landau (2005), ch. 7.

  7. 7.

    Here it is useful to compare our argument to an argument previously developed by Frank Jackson (1987). Jackson’s argument appeals to what he calls the “difference principle,” according to which “the morality of an action depends on the difference it makes; it depends, that is, on the relationship between what would be the case were the act performed and what would be the case were the act not performed.” He considers a case analogous to the case of the two torturers above, and appeals to the difference principle in order to argue that neither torturer’s action is wrong (pp. 94–96). Similarly, in the case of the stooges, Jackson might argue that neither stooge is obligated to try to carry the piano, simply because neither stooge would make a difference to the outcome by so doing. But this line of argument implies that neither Moe nor Larry would be obligated to try to carry the piano even if each stooge were unaware that the other will refuse to help. Similarly, in the torturer example, Jackson is committed to say that A can permissibly throw her switch even if A does not know that B will throw hers. Thus Jackson’s reasoning controversially presupposes that an agent’s knowledge is irrelevant to the agent’s obligations. By contrast, our argument relies on MR and RE, rather than Jackson’s difference principle; so it is open to us—but not to Jackson—to allow that each stooge’s obligations might depend on his knowledge of the other’s intentions and behavior.

  8. 8.

    Or so it seems. That is, it seems that Moe can truthfully say “I am unable to carry the piano upstairs (given that Larry is too lazy to help),” and it seems that Larry can truthfully say “I am unable to carry the piano upstairs (given that Moe is too lazy to help,” but it does not seem that Moe and Larry can truthfully say in unison, “We are unable to carry the piano upstairs (given that each of us is too lazy to help the other).” The fact that Moe and Larry are both lazy seems to incapacitate them as individuals but not as a group. We will provide support for this view in our discussion of joint capacities below, in Section 3.

  9. 9.

    Relatedly, Michael Zimmerman (1996) acknowledges the initial attractiveness of a group agency solution to difficulties posed by the sort of case exemplified by the stooges, but he finds the solution unacceptable. He writes: “the group wrongdoing is not attributable to any of the members of the group […] But this is too much to swallow; the scenario still smacks of two (individual) wrongs making a right” (pp. 262–63).

  10. 10.

    This possibility is not considered by Zimmerman.

  11. 11.

    As noted above, Zimmerman (1996) would object that if the stooges’ group action was wrong, then surely at least one stooge’s individual act must have been wrong as well (p. 255). But, contrary to Zimmerman, this entailment appears not to hold. Consider Jackson’s “Morning Traffic Example”: To ensure optimal safety, the group of morning commuters ought to adhere to the 60-kilometers-per-hour speed limit, and the group acts wrongly by driving at 80. But it is nonetheless true of each individual commuter that, given that everyone else is driving at 80, he ought to drive at 80 as well. So, arguably, while the group’s speeding is wrong, no individual commuter’s speeding is wrong (Jackson 1987, p. 102).

  12. 12.

    See Margaret Gilbert’s discussion of “membership guilt” (2002, pp. 134–35).

  13. 13.

    However, if there is such resistance, it probably should not be founded in the notion that an individual cannot find himself in a situation in which he cannot avoid having some sort of a reason to feel guilty for what he does, no matter what he does. That notion is deservedly controversial. Suppose, for instance, that Moe promised to meet Lisa for lunch at noon uptown, but also promised to meet Rita for lunch at noon downtown. He cannot avoid breaking a promise in this case. So it is not implausible to think that he will have a reason to feel guilty for what he does, whatever he does. Thus it looks as if there might well be some cases in which an agent cannot avoid having reasons to feel guilty.

  14. 14.

    Of course, there might be more than three agents in the room. Imagine, for instance, a view according to which [Moe, Larry] combines with Moe to form a fourth agent, [Moe, [Moe, Larry]]. But our position does not require this. We do not hold that just any collection of agents constitutes a group agent. In that respect, our view differs from that endorsed by Frank Jackson, who counts as group actions all sums of individual actions (and group actions). According to Jackson’s view, “[m]y last eye-blink together with Nero’s burning of Rome is a group action, a highly heterogeneous one of no particular interest to anyone, but a group action nevertheless” (1987, p. 93).

  15. 15.

    Thus, our position here is a bit more extreme than the position ingeniously developed at length by Philip Pettit and Christian List (2011). Pettit and List begin with a metaphysical account of agency, according to which agents have representational and motivational states, together with the ability to act on such states (p. 20). They then proceed to argue that, given this account of agency, certain types of groups are agents, and can thus bear moral responsibilities. By contrast, our argument begins with intuitively plausible moral judgments, such as DJS; we argue that these judgments provide reasons to endorse the metaphysical claim that certain obligation-bearing group agents, such as [Moe, Larry], exist. So Pettit and List move from metaphysics to morality, whereas we move from morality to metaphysics. This move, we believe, commits us to a significantly more permissive conception of agency than the conception endorsed by Pettit and List. For instance, we have to say that a group that exhibits thoroughgoing irrationality can be an agent, whereas Pettit and List can deny this.

  16. 16.

    Note that this position does not commit us to the view that every group of agents constitutes a group agent. For instance, the current inhabitants of Earth (taken as a whole) probably do not count as a group agent on our account, because the current inhabitants of Earth are probably not jointly capable of acting in response to reasons.

  17. 17.

    Here it ought to be noted that many of the groups that qualify as group agents on our account are extremely unlikely to act in accordance with their obligations. For instance, in the piano case, it is virtually certain that [Moe, Larry] will fail to carry the piano upstairs; given this, there seems to be no injunctive point to saying that [Moe, Larry] bears an obligation to carry the piano upstairs. This looks like a problem for our view. However, there are in fact many cases in which a moral judgment is correct and appropriate despite having no injunctive point. For instance, one can correctly and appropriately judge that Jeffrey Dahmer’s killings were morally wrong, even though this judgment will be neither heard nor heeded—since the killings have already been done, and Dahmer is already dead. Similarly, if someone is now planning to commit a murder, it ought to be said that he is morally obligated not to do so, even if it is virtually certain that he will proceed with his plan. In general, moral judgments can be worth making even when there is no injunctive point in making them.

  18. 18.

    We do not claim that Sinnott-Armstrong endorses this argument, although he might. In any case, if he did endorse this argument, he would have much more to say than we can say here about why the conditional “If going on a Sunday drive is harmless, then it is morally permissible” is true.

  19. 19.

    For some interesting, although questionable, objections to Sinnott-Armstrong’s view, see Hiller (2011).

  20. 20.

    It has been estimated that global warming will lead to the suffering and death of four billion people. See Nolt (2011).


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We are immensely grateful to Jeff Behrends, Harry Brighouse, Justin Horn, Matt Kopec, Jonathan Lang, Pete Nichols, and Russ Shafer-Landau for their feedback, advice, and conversation regarding previous drafts of this paper.

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Correspondence to Bekka Williams.

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Killoren, D., Williams, B. Group Agency and Overdetermination. Ethic Theory Moral Prac 16, 295–307 (2013).

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  • Group agency
  • Overdetermination
  • Climate change
  • Electoral politics