PDF《Actualism, Possibilism, and Beyond1》

Jacob Ross Actualism, Possibilism, and Beyond1 How is what an agent ought to do related to what an agent ought to prefer that she does? More precisely, suppose we know what an agent'

s preference ordering ought to be over the outcomes of performing the various courses of action open to her.

Can we infer from this information how she ought to act, and if so, how can we infer it? One view (which, for convenience, I will call '

actualism'

) is that an agent ought to φ just in case she ought to prefer the outcome that would result from her φ-ing to the outcome of that would result from her not φ-ing.2 Another view (which, for convenience, I will call '

possibilism'

) is that an agent ought to φ just in case all of her options (in the relevant domain) with maximally preferable outcomes involve φ-ing. I will discuss actualism and possibilism in parts

1 and 2, respectively. I will argue, in part 1, that actualism is very far from the truth. And I will argue, in part 2, that while the standard version of possibilism faces significant problems, there are much better versions of possibilism that avoid the objections to the standard view. Ultimately, however, I will argue that even the best forms of possibilism are not acceptable. Then, in part 3, I will offer a diagnosis of why the existing theories fail, and I will offer an alternative theory that is neither actualist nor possibilist in form, and that avoids the difficulties with the other theories. 1. Actualism 1.1 The Absurdity of Actualism The main problem with actualism is that it'

s obviously false. This can be seen if we consider the following case:

1 ?I am very grateful to my colleagues Kenny Easwaran, Mark Schroeder, and Gideon Yaffe for many invaluable discussions concerning this paper. I owe a special debt to Shieva Kleinschmidt for extremely helpful comments on several drafts of this paper. My greatest debt to Doug Portmore. Many of the key ideas in this paper arose in the course of a correspondence I had with him during the summer of 2010. Had it not been for this correspondence, this paper could not have been written.?

2 ?Examples of actualism are Sobel (1976) and Jackson and Pargetter (1986). Examples of possibilism are Feldman (1986) and Zimmerman (1996).? ? 2? Arsenic and Old Ace: Absentminded Ace is looking after his three year old granddaughter Emily, who asks him for a glass of water. As a matter of fact, Ace is about to accidentally give Emily a glass containing an arsenic solution. When he does so, she will drink the contents of the glass and die. Ace has many options besides giving Emily the arsenic. He could instead give her a glass of water as she requested. Or he could give her a glass of Drano, or a glass of bleach, or a glass of ammonia. If he were to give her glass of water, she would drink it and be happy. If, on the other hand, he were to give her a glass of a glass of Drano, bleach, or ammonia, then while she would not drink enough of the liquid for it to be fatal, she would drink enough to suffer severe and irreversible damage to her mouth and esophagus.3 Of the options just described, it seems fairly obvious that there is only one that Ace ought to carry out: he ought to give Emily a glass of water. And there are many that he ought not to carry out: he ought not to give her arsenic, he ought not to give her Drano, he ought not to give her bleach, and he ought not to give her ammonia. The actualist, however, disagrees. The actualist says that, objectively speaking, Ace ought to give Emily Drano. For the nearest world in which Ace doesn'