Abstract
If David Lewis’s modal realism (MR) is true, then there are many, many people. According to Mark Heller, this is bad news. He takes MR to imply that “there are at least some cases in which it is permissible to let drowning children drown when it would be easy to save them.” But since he holds the reasonable view that this is never permissible, he thinks that MR is false. Here, I argue that Lewis needn’t be troubled by this objection: it provides no reason to reject MR for those who share Lewis’s moral outlook. Moreover, I argue that disagreement with common sense needn’t be severe if we can show both (a) that there’s a sense in which common sense is correct and (b) we have little reason to care about the sense in which common sense is mistaken.
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Notes
Heller’s characters are Roz and Lisa. To streamline exposition, I want to be able to distinguish the characters by their respective genders. Also, Heller provides scenarios with the relevant structure, but their details just serve to motivate responses to objections that we can ignore here.
…or if it matters, it’s in a way that doesn’t help Lewis. See (2003, p. 4) for details.
Not incidentally, the above helps Heller address a different objection. It’s true of both Abby and Abby* that each can act even if the other acts too—that is, what’s guaranteed by plenitude is that if Abby acts, someone doesn’t, not that if Abby acts, someone is prevented from acting. So each is responsible for what she does—not for what the other does. Fair enough, but that doesn’t give Lewis a way out. Whether or not Abby* is prevented from acting, Abby knows that Abby* will let a child drown if Abby saves a child, as well as that she won’t if Abby doesn’t. Granted, Abby* will do this freely, and she’s responsible for what she does. But the lives of both children matter, and it’s no consolation to Abby—or to the child in Abby*’s world—that Abby* is choosing a dark path. Heller’s point is just that it’s permissible to save the child in Abby*’s world by failing to act in the actual world—not that Abby is responsible for what Abby* does. If we’d like to be somewhat dramatic, we can think of Abby as faced with a choice between saving a child near her and saving Abby*’s hostage. The choice is a tragic one, and she can’t be faulted whatever she decides.
Setting things up this way is a bit misleading, since it suggests a debate between Lewis and another party. Of course, Lewis thinks of himself as a proponent of common sense.
This idealization is possible because of how Heller sets up the case. Abby knows that, if she acts, she’ll be successful; so, she doesn’t need to consider the various worlds in which she tries to save the child, and fails. Likewise, Abby knows that child will drown if she doesn’t act, so she doesn’t need to consider the various worlds in which, e.g., someone else saves the child, or the child happens to be washed ashore, etc. Still, there are countless subtle (and not so subtle) variations between worlds in which Abby successfully saves the child (one has a seagull fly overhead during the saving, another doesn’t; one has her take x strokes as she swims out to the child, the other has her taking x + 1 strokes; etc.), and just as many variations between the worlds in which she doesn’t. But those differences don’t matter for the purposes of moral assessment, so we can ignore them.
N.B., this isn’t to suggest that we completely ignore the possibility that isn’t actualized when we make a restricted moral judgment. We compare actuality to the other possibility when we praise or blame her, and she compares actuality to the other possibility when she is proud of, or regrets, her choice.
Compare: according to epistemic contextualists, there are contexts in which I may ignore the possibility that I’m being deceived by an evil demon; when I’m in them, it’s clear that I know that I have hands. After all, the only way to criticize this knowledge claim would be to appeal to the possibility that I’m permissibly ignoring—namely, that I’m being deceived by the demon. So, when I consider all possibilities, I lack knowledge; but when I don’t consider them, I have it. In a sense, MR commits Lewis to a kind of moral contextualism.
This reply works equally well for a variant of the Objection. Consider: whatever Abby does in the two-world case, one child is saved and another drowns. So suppose she opts to save the child in the actual world, which is certainly permissible. However, given what Abby knows about what her counterpart therefore fails to do, it would be reasonable for her to regret what she did, since her action ensured that a child drowned in some other world. But according to the variant of the Objection, it would be absurd to regret having the saved the life of a child. So, MR is false.
I agree: it would indeed to be absurd to regret having the saved the life of a child when permissibly ignoring the existence of non-actual persons. However, Lewis can maintain that it isn’t absurd to regret having the saved the life of a child when we don’t ignore the existence of non-actual persons. As it happens, we rarely—if ever—have reason not to ignore them, so things seem deeply counterintuitive from that vantage point. That, however, is no more an objection—and no less—than the observation that it’s deeply counterintuitive to countenance the existence of talking donkeys.
The man on the street doesn’t distinguish between the claim that there aren’t actually any non-actual people and the claim that there aren’t any non-actual people simpliciter. So, he holds both beliefs or neither; he doesn’t hold neither; so, he holds both.
In part, this may be because so much of common sense morality is Moorean. But whether or not it’s Moorean, we still answer to it as part of common sense.
See Quine (1981) for more on this.
Thanks to Eric Gilbertson for many helpful conversations about the ideas in this paper. I’m also grateful to two anonymous reviewers—the second in particular—who provided more detailed and thoughtful feedback than I’ve ever received on a submission.
References
Adams, R. (1974). Theories of actuality. Noûs, 8(3), 211–231.
Heller, M. (2003). The immorality of modal realism, or: how I learned to stop worrying and let the children drown. Philosophical Studies, 114, 1–22.
Lewis, D. (1986). On the plurality of worlds. New York: Blackwell.
Nagel, T. (1971). The absurd. The Journal of Philosophy, 68(20), 716–727.
Quine, W. V. O. (1981). Theories and things. Cambridge: Harvard University Press.
Smart, J. J. C. (1984). Ethics, persuasion and truth. London: Routledge and Kegan Paul.
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Fischer, B. The Moral Objection to Modal Realism. Erkenn 82, 1015–1030 (2017). https://doi.org/10.1007/s10670-016-9856-0
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DOI: https://doi.org/10.1007/s10670-016-9856-0