Staking our future: deontic long-termism and the non-identity problem

Andreas Mogensen (Global Priorities Institute, Oxford University)

GPI Working Paper - No. 9-2019

Greaves and MacAskill argue for ​axiological longtermism​, according to which, in a wide class of decision  contexts, the option that is ​ex  ante best is the option that corresponds to the best lottery over histories from ​t onwards, where ​t ​is some date far in the future. They suggest that a ​stakes-sensitivity argument may be used to derive ​deontic longtermism from axiological longtermism, where deontic longtermism holds that in a wide class of decision contexts, the option one ought to choose is the option that corresponds to the best lottery over histories from ​t onwards, where ​t is some date far in the future. This argument appeals to the ​Stakes Principle​: when the axiological stakes are high, non-consequentialist constraints and prerogatives tend to be insignificant in comparison, so that what one ought to do is simply whichever option is best. I argue that there are strong grounds on which to reject the ​Stakes Principle​. Furthermore, by reflecting on the Non-Identity Problem, I argue that there are plausible grounds for denying the existence of a sound argument from axiological longtermism to deontic longtermism insofar as we are concerned with ways of improving the value of the future of the kind that are focal in Greaves and MacAskill’s presentation.

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