PhilSci Archive

The Lion, the 'Which?' and the Wardrobe -- Reading Lewis as a Closet One-boxer

Price, Huw (2009) The Lion, the 'Which?' and the Wardrobe -- Reading Lewis as a Closet One-boxer. [Preprint]

WarningThere is a more recent version of this item available.

Download (1MB)


Newcomb problems turn on a tension between two principles of choice: roughly, a principle sensitive to the causal features of the relevant situation, and a principle sensitive only to evidential factors. Two-boxers give priority to causal beliefs, and one-boxers to evidential beliefs. A similar issue can arise when the modality in question is chance, rather than causation. In this case, the conflict is between decision rules based on credences guided solely by chances, and rules based on credences guided by other sorts of probabilistic evidence. Far from excluding cases of the latter kind, Lewis’s Principal Principle explicitly allows for them, in the form of the caveat that credences should only follow beliefs about chances in the absence of "inadmissible evidence". In this paper I exhibit a tension in Lewis’s views on these two matters. I present a class of decision problems –- actually, I argue, a species of Newcomb problem –- in which Lewis’s view of the relevance of inadmissible evidence seems to recommend one-boxing, while his causal decision theory recommends two-boxing. I propose a diagnosis for this dilemma, and suggest a remedy, based on an extension of a proposal due to Ned Hall and others from the case of chance to that of causation. The remedy dissolves many apparent Newcomb problems, and makes one-boxing non-controversial in those that remain.

Export/Citation: EndNote | BibTeX | Dublin Core | ASCII/Text Citation (Chicago) | HTML Citation | OpenURL
Social Networking:
Share |

Item Type: Preprint
Price, Huw
Additional Information: With the kind permission of Wlodek Rabinowicz, Stephanie Lewis and the Estate of David K. Lewis, this preprint includes as an Appendix some correspondence between Rabinowicz and Lewis in 1982, to which reference is made in the text.
Keywords: Newcomb, chance, causation, decision theory, David Lewis
Subjects: Specific Sciences > Probability/Statistics
General Issues > Decision Theory
General Issues > Causation
Depositing User: Prof Huw Price
Date Deposited: 15 Sep 2009
Last Modified: 07 Oct 2010 15:18
Item ID: 4894

Available Versions of this Item

Monthly Views for the past 3 years

Monthly Downloads for the past 3 years

Plum Analytics

Actions (login required)

View Item View Item