In Richard Bradley’s book, Decision Theory with a Human Face, we have selected two themes for discussion. The first is the Bolker-Jeffrey theory of decision, which the book uses throughout as a tool to reorganize the whole field of decision theory, and in particular to evaluate the extent to which expected utility theories may be normatively too demanding. The second theme is the redefinition strategy that can be used to defend EU theories against the Allais and Ellsberg paradoxes, a strategy (...) that the book by and large endorses, and even develops in an original way concerning the Ellsberg paradox. We argue that the BJ theory is too specific to fulfil Bradley’s foundational project and that the redefinition strategy fails in both the Allais and Ellsberg cases. Although we share Bradley’s conclusion that EU theories do not state universal rationality requirements, we reach it not by a comparison with BJ theory, but by a comparison with the non-EU theories that the paradoxes have heuristically suggested. (shrink)

Abstract:One view of practical reasoning is that it involves the weighing of reasons. It is not clear, however, how the weights of reasons combine, especially given the logical and substantive relations among different reasons. Nor is it clear how the weighing of reasons relates to decision theoretic maximization of expected value. This paper constructs a formal model of reasons and their weight in order to shed light on these issues. The model informs philosophical debates about reasons, such as the question (...) of whether reasons or values are more fundamental and the opposing doctrines of atomism and holism about reasons. (shrink)

With characteristic incisiveness Georg Henrik von Wright identifies pro­ haireticIogic (i. e. the logic of preference) as the core of a general theory of value concepts. Essentially, this nucleus involves the logical study of acts from the point of view of their preferability. 1 (italics added) Though the term prohairesis is found in Plato, as well as in Aristotle's treatment of the relations of preference, it is von Wright who introduces this word into contemporary analytical philoso­ phy, and succinctly specifies (...) the philosophical dimensions it encompasses. The above emphasis upon the philosophical study of the formalization of preferences is a matter of utmost importance for understanding the type of in­ quiry this investigation attempts to initiate. Over the past one hundred years the literature on general theories of subjective utility has become massive, where one considers the work done in psychometrics, econometrics, statistical theories, probability theories, etc., etc. Histories in these areas are strong in tracing various evolutions in the development of the concept of preference in decision-making. However, what has not been investigated with sustained at­ tention are the fundamentally philosophical inquiries into the formalization of preference-relations. (shrink)

In his Truth and Probability (1926), Frank Ramsey provides foundations for measures of degrees of belief in propositions and preferences for worlds. Nonquantitative conditions on preferences for worlds, and gambles for worlds and certain near-worlds, are formulated which he says insure that a subject's preferences for worlds are represented by numbers, world values. Numbers, for his degrees of belief in propositions, probabilities, are then defined in terms of his world values. Ramsey does not also propose definitions of desirabilities for propositions, (...) though he is in a position to do this. Given his measures for probabilities of propositions and values of worlds, he can frame natural definitions for both evidential and causal desirabilities that would measure respectively the welcomeness of propositions as items of news, and as facts. His theory is neutral with respect to the evidential/causal division. In the present paper, as Ramsey's foundations are explained, several problems and limitations are noted. Their distinctive virtue – their evidential/causal neutrality – is demonstrated. Comparisons are made with other foundational schemes, and a perspective is recommended from which nonquantitative foundations are not the be all for quantitative theories of ideal preferences and credences. (shrink)