Volume 2, Issue 3, 2002
Theories of Rationality
The Pragmatic Stance
Whither Dutch Books and Money Pumps?
The view that decision methods can only be justified by appeal to pragmatic considerations is defended. Pragmatic considerations are viewed as providing the underlying subject matter (“semantics”) of decision theories. It is argued that other approaches (e.g. justifying principles by appeal to obviousness, common usage, etc.) fail to provide grounds for a normative decision theory.
It is argued that preferences that can lead to pragmatically adverse outcomes in a relevantly similar possible decision situation are pragmatically unsound, even if the decision situation never arises. This rebuts several standard objections to money-pump and Dutch book arguments. However, because one can only appeal to relevantly similar decision situations in pragmatic arguments, these will have a less general scope than is often imagined. A conclusion is that pragmatic arguments for strong unconditional principles such as ‘always maximise expected utility!’ do not work. Pragmatic considerations can however be used to argue for conditional principles of the form ‘if conditions X, Y and Z are satisfied, then one ought to satisfy W’, where W need not follow logically from X, Y and Z.
The notion of a sound pragmatic argument is defined in terms of particular notion of coherence, it is shown how this can be applied and how it handles problematic cases such as van Fraassen’s Dutch book for the principle of Reflection.