PDF《Actualism, Possibilism, and Beyond1》

ought'

claims are implicitly relativized to sets of options. When we ask whether Ace ought to give Emily Drano, the relevant set of options consists of just two alternatives: {giving Emily Drano;

not giving Emily Drano}. But when we ask what she ought to do at noon, the relevant set of options will be {giving Emily Drano;

giving Emily bleach;

giving Emily ammonia;

giving ? 4? Emily the arsenic solution;

giving Emily water}. Thus, there is no conflict between the claim that Ace ought to give Emily Drano at noon and the claim that giving Emily Drano is no part of what Ace ought to do at noon. For the former claim is implicitly relativized to the first, more coarse-grained partition of options, whereas the latter claim is implicitly relativized to the second, more fine-grained partition of options.4 As I see it, however, this contextualist maneuver doesn'

t really solve the problem we discussed in the last section, for it retains the implausible implication that Ace ought to give his granddaughter Drano (or, in the formal mode, that utterances of the sentence '

Ace ought to give his granddaughter Drano'

are true). Further, even if it isn'

t strictly incoherent, is still fails to respect the intuitive connection between question of whether to φ at t and the question of what to do at t. Moreover, it introduces a further problem, which can be seen if we consider the following case. President Muffley: It is now noon. President Merkin Muffley had accidentally activated the Doomsday Machine. Before him are two buttons, A and B. At 12:01, he will have exactly three options: he can press button A, he can press button B, or he can press neither button. If and only if he presses neither button at 12:01, at 12:02 he will have the opportunity to press button A. The outcomes for the various courses of action open to him are as follows: ? Press button A 12:01: 30% of the world destroyed ? Press button B at 12:01: 70% of the world destroyed ? Press neither button at 12:01;

press button A at 12:02: 0% of the world destroyed ? Press neither button at either time: 100% of the world destroyed Muffley knows that he himself will die right after 12:02, and he is indifferent to the fate of the world after his death. Thus, he has made up his mind about what to do by tossing coins. As a result, he will press neither button at 12:01, and regardless of what he does at 12:01, he will press neither button at 12:02. On Jackson and Pargetter'

s contextualist view, when we ask whether Muffley ought to press only button B at 12:01, the relevant options are pressing only button B at 12:01 and not pressing only button B at 12:01. And since the former would result in 70%, rather than 100%, of the world being destroyed, the following claim is true: (i) Muffley ought to press only button B at 12:01.

4 ?For other views on which '

ought'

claims are relativized to sets of options, see Cariani (forthcoming) and Snedegar (forthcoming).? ? 5? For similar reasons, if we ask whether Muffley ought to press only button A at 12:01, the answer will again be affirmative, so the following is true: (ii) Muffley ought to press only button A at 12:01. But now suppose we ask not whether Muffley ought to perform a given action, but rather what he ought to do at a given time. Suppose we ask, first, what he ought to do at 12:01. Here the relevant options will be all the max........