Ideas from 'The Logic of Decision' by Richard Jeffrey [1965], by Theme Structure

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10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / b. Worlds as fictions
A possible world can be seen as a complete and consistent novel
                        Full Idea: A novel describes a possible world in as much detail as is possible without exceeding the resources of the agent's language. But if talk of possible worlds seems dangerously metaphysical, focus on the novels themselves, when complete and consistent.
                        From: Richard Jeffrey (The Logic of Decision [1965], 12.8), quoted by David Lewis - On the Plurality of Worlds
                        A reaction: Lewis seems to cite this remark from Jeffrey as the source of the idea that ersatz linguistic worlds are like novels. Why won't a novel with one tiny inconsistency count as a possible world? People seem to live in it.
14. Science / C. Induction / 6. Bayes's Theorem
Instead of gambling, Jeffrey made the objects of Bayesian preference to be propositions
                        Full Idea: Jeffrey produced a version of Bayesianism that made no direct use of gambling (as Ramsey had), but treats the objects of preference ...as propositions.
                        From: report of Richard Jeffrey (The Logic of Decision [1965]) by Donald Davidson - Truth and Predication 3
                        A reaction: I'm guessing that Jeffreys launched modern Bayesian theory with this idea. It suggest that one can consider degrees of truth, rather than mere winning or losing.