Abstract
There has been considerable debate regarding the relative merits of two theses about moral obligation known as actualism and possibilism. Both theses seek to give expression to the general idea that one ought to do the best one can. According to actualism, one’s obligations turn on what would happen if one chose some course of action, whereas, according to possibilism, they turn on what could happen (i.e., what one could make happen) if one chose some course of action. There are two strands to the debate: the substantive verdicts that the two theses render in particular cases, and the accounts that they yield of the conceptual structure of moral obligation. Possibilism is conceptually appealing, whereas actualism is not, but the latter may seem to render superior substantive verdicts. In this paper, it is argued that, by turning from the objectivist’s emphasis on what is actually best to the prospectivist’s emphasis on what one’s evidence indicates is best, possibilists can provide an account of moral obligation that is both conceptually and substantively attractive.
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Notes
Throughout this paper, I will use “act” broadly to cover any form of voluntary behavior, including omission.
Another, closely-related formulation of actualism is this:
P ought to do some act A if and only if P can do A and what would happen if P did A is better than what would happen if P performed any alternative to A.
This formulation has the advantage of (apparently) avoiding the third of the objections to actualism that I will be discussing in Section II below, but (a) it does not avoid the first two objections and (b) it has the disadvantage of relying on the unexplained concept of an alternative. (For discussion of some of the difficulties with providing an acceptable account of this concept, see Bergström 1966; Carlson 1999; Bykvist 2002.) Both formulations of actualism are discussed in Zimmerman (1996: ch. 6).
It is perhaps most natural to think of the case in a consequentialist light, but this is certainly not necessary. One might, for example, regard A&S as the best way for Rick to show due respect to the author of the book and/or the editor of the journal that solicited the review, while A&~S would be the most disrespectful way in which he could behave under the circumstances.
In Case 1, let A = accept and B = submit. In Case 2, let A = not-accelerate and B = not-change.
In Case 1, let A = accept-and-submit and B = accept. In Case 2, let A = not-accelerate-and-not-change and B = not-accelerate.
Just what constitutes one act’s being a part of another is a matter of debate, as is the structure of action generally. (For rival accounts, see Goldman 1970: ch. 2; Thomson 1977: chs. 4–7.) There is also some debate about whether there can be maximal combinations of acts. (For discussion, see Brown 2017: pp. 11–13.) There is no space to explore these issues here. Also, I understand that it is a little off-putting to call an individual act a combination of acts (even if only a “minimal” one), but doing so simplifies the discussion to follow.
This formulation of possibilism is heavily indebted to the account of unconditional obligation given in Feldman (1986: ch. 2). Cf. also Zimmerman (1996: 26–27), and Portmore (2013: 448). (In Portmore 2011, p. 207 ff., Portmore declines to call the view that he espouses a version of possibilism, but that is primarily just a matter of terminological preference. Recently, the term “maximalism” has come to be applied to accounts of obligation whose form resembles this formulation of possibilism, although there are some subtle differences in just how the term has been used. See Bykvist 2002; Gustafsson 2014; Portmore 2016; Brown 2017.)
Note that this formulation of possibilism presupposes that it makes sense to say that someone both ought to and can at some time perform some action at some later time. Some philosophers appear to reject this idea (e.g., Jackson 2014: 636), but it seems to me unassailable. Consider Rick. Suppose that he promises on the 1st to submit the review on the 15th. It seems clear that, under normal conditions, he both can and, perhaps, ought on the 1st to submit the review on the 15th.
In saying that the idea of such “remote” ability and obligation is unassailable, I don’t mean that it is obvious just how these phenomena are to be understood. There is, for example, disagreement regarding what one’s being able at some time to perform some action at some later time comes to. Must it be the case that one can at the earlier time ensure that one will perform the action at the later time (Goldman 1978: 195), or does some less stringent condition suffice (Goldman 1976: 453–454)? I won’t explore the issue here, although I would argue for a less stringent condition.
Also, in saying that P can at T perform some maximal combination of acts, I of course do not mean that P can at T complete the performance of that combination at T. Obviously, this cannot be the case, if some of the acts included in that combination will, if performed, occur only at some later time T'. What I mean is that, for any act A that is included in the combination and which, if performed, would occur at some later time T', P can at T perform A at T'.
I should note that, on the view I embrace, if P ought at T to do A at T′, then it is true not only that P can at T do A at T′ but also that P can at T refrain from doing A at T′. This requires that principles (1) and (2) be modified slightly. See Zimmerman (1996: 66 ff. and 73 ff.).
This formulation is heavily indebted to the account of conditional obligation given in Feldman (1986, ch. 4). Cf. Zimmerman (1996: 119). By “P can at T do A at T′ while p is true” I mean that P can at T see to it that the proposition (p & P does A at T′) is true. There are two possibilities. Either p will be true no matter what P does at T—as when, for example, p = Ethiopia will continue to be stricken by drought. Or it is within P’s control at T to make it both the case that p and the case that P does A at T′—as, for example, in Case 1, in which it is within Rick’s control on the 1st to make it both the case that he declines the invitation on the 1st and the case that he does not submit the review on the 15th.
In this respect, judgments of conditional obligation—which, let us stipulate, have the form “O(q/ p)”—resemble judgments regarding wide-scope “oughts” of the form “O(p → q)” (regarding which see, e.g., Broome 1999). Indeed, it is provable that, according to objective possibilism, O(q/ p) only if O(p → q) (but not vice versa). In light of this implication, the question arises why we should construe some judgments as having the particular form of “O(q/ p)” rather than the more general form of “O(p → q).” For discussion, see Zimmerman (2015, p. 170 ff.).
I should add that there nonetheless is a way to detach the relevant unconditional obligation that is consistent with all that I have said so far, as long as the unconditional obligation is declared “subsidiary” to the agent’s primary unconditional obligation. See Zimmerman (1996, p. 128 ff.).
See Zimmerman (1996, ch. 8) for further discussion of how to reconcile supererogation with the general idea that one ought to do the best one can.
For example, it might be contended that knowingly doing the wrong thing suffices for blameworthiness and that, since, if he declined the invitation, Rick would knowingly do so, then, if it would be wrong for him to do so, he would be to blame for doing so. But this can be disputed in turn. Certainly, if Rick declined the invitation, he would knowingly do so, but, unless he knew that it was wrong for him to do so, it seems reasonable to think that he might not be to blame for doing so. The ironic conclusion is that, if Rick subscribed to objective possibilism, he would be to blame for declining the invitation, but otherwise he might not be.
This case has been adapted from Zimmerman (2008: 124–125).
Note that even actualists typically draw it. Cf. Moore (2005: 97 ff.).
Other evidence-related senses can be distinguished. For example, Jackson (1991: 471–472) mentions “oughts” that are indexed to the agent’s evidence at some time after the performance of the relevant action, to one or another onlooker’s evidence, to God’s evidence sub specie aeternitatis… Kiesewetter (2011: 16ff.) focuses on an “ought” that is indexed to certain evidence that the agent would have if he conducted himself in a certain way. And no doubt other evidence-related senses could be distinguished. As I see it, the sense with which I am concerned enjoys an intuitive priority over the others, in terms of its moral significance, but I will not try to argue for this claim here. Moreover, I should note that what an agent ought in the present sense to do is not a function solely of the evidence that he has at the time at which the “ought” applies. On the contrary, as I will be arguing, it is also a function of what he can at that time do—something which, in the case of remote obligation, also brings later times into play.
This formulation of course concerns only unconditional obligation. I will turn to a discussion of conditional obligation below.
I am deeply indebted to Benjamin Kiesewetter for alerting me to this problem.
More precisely, the solid and empty circles represent choice- and chance-points, respectively, for Tim. Clearly, it is up to the baker whether a or p occurs, and so for him the relevant circle would be solid. On choice- versus chance-points, see McClennen (1990: 7 ff.), and Rabinowicz (1995: 589 ff.).
Note that prescriptions may be disjunctive. A prescription to do either A or B may be understood as leaving it up to the agent which of A and B to choose. Cf. Zimmerman (1996, pp. 35–37).
Note that in such a case PP4 would not imply that Rick has an obligation to decline the invitation. His doing so would continue not to feature in the prospectively best feasible plan and so would remain non-obligatory. (In the limiting case, if the prospectively best plan that is feasibly implemented by an agent is such that he can in fact do nothing that is featured in that plan, PP4 implies that that agent has no obligations whatsoever.) This point contradicts a presupposition made in Way and Whiting (2016, 1888), where an argument is given for the claim that prospectivists should reject the principle that “ought” implies “can.”
Those (such as Adams 1977; van Inwagen 1997) who subscribe to a libertarian view of freedom of action would (probably) favor the “would probably” over the “would” formulation and therefore opt for a probabilized version of objective possibilism, if they were to opt for any. Even so, I see no reason to think that the objective probabilities invoked by them must be of the same kind as those at issue in Case 4.
On some occasions our evidence justifies our taking it to be a practical certainty that we can make a certain choice but not that we can thereby achieve a certain outcome. Figure 4 represents its being practically certain for Jill that she can turn the dial but not that she can thereby open the safe. It could be that, in another version of the case, it is practically certain for her that she can choose to turn the dial (or, perhaps better, that she can choose to try to turn it) but not that she can turn it.
See n. 11 above.
It might seem that, given the validity of inferences of the form “if p were true, then q would be true; p is true; therefore q is true” (Lewis 1973: 27), we should say that what I have called conditional obligation is a special case of what I have called contingent obligation. But this would be a mistake, I think, since an agent’s evidence may not indicate that such inferences are valid.
Many thanks to an anonymous referee for The Journal of Ethics, to Erik Carlson, and especially to Benjamin Kiesewetter for very helpful comments on previous versions.
References
Adams, Robert Merrihew. 1977. Middle knowledge and the problem of evil. American Philosophical Quarterly 14: 109–117.
Åqvist, Lennart. 1969. Improved formulations of Act-Utilitarianism. Noûs 3: 299–323.
Bergström, Lars. 1966. The alternatives and consequences of actions. Stockholm: Almqvist & Wiksell.
Broome, John. 1999. Normative requirements. Ratio 12: 398–419.
Brown, Campbell. 2017. Maximalism and the structure of acts. Noûs. doi:10.1111/nous.12181.
Bykvist, Krister. 2002. Alternative actions and the spirit of consequentialism. Philosophical Studies 107: 45–68.
Carlson, Erik. 1999. Consequentialism, alternatives, and actualism. Philosophical Studies 96: 253–268.
Feldman, Fred. 1986. Doing the best we can. Dordrecht: D. Reidel.
Forrester, James. 1984. Gentle murder, or the adverbial Samaritan. Journal of Philosophy 86: 193–197.
Goldman, Alvin I. 1970. A theory of human action. Princeton: Princeton University Press.
Goldman, Holly S. 1976. Dated rightness and moral imperfection. Philosophical Review 85: 449–487.
Goldman, Holly S. 1978. Doing the best one can. In Values and morals, ed. Goldman, Alvin I., and Jaegwon Kim, 185–214. Dordrecht: D. Reidel.
Gustafsson, Johan E. 2014. Combinative consequentialism and the problem of act versions. Philosophical Studies 167: 585–596.
Jackson, Frank. 1991. Decision-theoretic consequentialism and the nearest and dearest objection. Ethics 101: 461–482.
Jackson, Frank. 2014. Procrastinate revisited. Pacific Philosophical Quarterly 95: 634–647.
Jackson, Frank, and Robert Pargetter. 1986. Oughts, options, and actualism. Philosophical Review 95: 233–255.
Kiesewetter, Benjamin. 2011. ‘Ought’ and the perspective of the agent. Journal of Ethics and Social Philosophy 5: 1–24.
Lewis, David. 1973. Counterfactuals. Cambridge, Mass.: Harvard University Press.
McClennen, Edward F. 1990. Rationality and dynamic choice. Cambridge: Cambridge University Press.
Mele, Alfred R. 2003. Agents’ abilities. Noûs 37: 447–470.
Moore, G.E. 2005. Ethics. Oxford: Oxford University Press.
Parfit, Derek. 2011. On what matters, vol. 1. Oxford: Oxford University Press.
Pollock, John L. 1983. How do you maximize expectation value? Noûs 17: 409–421.
Portmore, Douglas W. 2011. Commonsense consequentialism. Oxford: Oxford University Press.
Portmore, Douglas W. 2013. Perform your best option. Journal of Philosophy 110: 436–459.
Portmore, Douglas W. 2016. Maximalism versus omnism about permissibility. Pacific Philosophical Quarterly. doi:10.1111/papq.12186.
Rabinowicz, Wlodek. 1995. To have one’s cake and eat it, too: Sequential choice and expected-utility violations. Journal of Philosophy 92: 586–620.
Ross, Jacob. 2013. Actualism, possibilism, and beyond. In Oxford studies in normative ethics, vol. 2, ed. Mark Timmons, 74–96. Oxford: Oxford University Press.
Sobel, Jordan Howard. 1976. Utilitarianism and past and future mistakes. Noûs 10: 195–219.
Thomson, Judith Jarvis. 1977. Acts and other events. Ithaca: Cornell University Press.
van Inwagen, Peter. 1997. Against middle knowledge. Midwest Studies in Philosophy 21: 225–236.
Vorobej, Mark. 2000. Prosaic possibilism. Philosophical Studies 97: 131–136.
Way, Jonathan, and Daniel Whiting. 2016. If you justifiably believe that you ought to Φ, you ought to Φ. Philosophical Studies 173: 1873–1895.
Woodard, Christopher. 2009. What’s wrong with possibilism. Analysis 69: 219–226.
Zimmerman, Michael J. 1996. The concept of moral obligation. Cambridge: Cambridge University Press.
Zimmerman, Michael J. 2008. Living with uncertainty. Cambridge: Cambridge University Press.
Zimmerman, Michael J. 2014. Ignorance and moral obligation. Oxford: Oxford University Press.
Zimmerman, Michael J. 2015. Moral requirements. In Weighing and reasoning, ed. Hirose, Iwao and Andrew Reisner, 156–176. Oxford: Oxford University Press.
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Zimmerman, M.J. Prospective Possibilism. J Ethics 21, 117–150 (2017). https://doi.org/10.1007/s10892-017-9245-1
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DOI: https://doi.org/10.1007/s10892-017-9245-1