Some arguments against David Lewis’s modal realism seek to exploit apparent inconsistencies between it and anthropic reasoning. A recent argument, in particular, seeks to exploit an inconsistency between modal realism and typicality anthropic premises, premises common in the literature on physical multiverses, to the effect that observers who are like human observers in certain respects must be typical in the relevant multiverse. Here I argue that typicality premises are not applicable to the description of Lewis’s metaphysical multiverse, where the proportions (...) of metaphysically possible observers possessing the pertinent properties can be independently established by metaphysical reasoning. However, other kinds of reasonable anthropic premises can be seen to be consistent with and usable within modal realism. (shrink)

This paper examines from a historical perspective Tarski's 1936 essay, "On the concept of logical consequence." I focus on two main aims. The primary aim is to show how Tarski's definition of logical consequence satisfies two desiderata he himself sets forth for it: (1) it must declare logically correct certain formalizations of the -rule and (2) it must allow for variation of the individual domain in the test for logical consequence. My arguments provide a refutation of some interpreters of Tarski, (...) and notably John Etchemendy, who have claimed that his definition does not satisfy those desiderata. A secondary aim of the paper is to offer some basic elements for an understanding of Tarski's definition in the historical logico-philosophical context in which it was proposed. Such historical understanding provides useful insights on Tarski's informal ideas on logical consequence and their internal cohesion. (shrink)

I postulate that the extension of a degree adjective is fixed by implicitly accepted non-analytic reference-fixing principles (“preconceptions”) that combine appeals to paradigmatic cases with generic principles designed to expand the extension of the adjective beyond the paradigmatic range. In regular occasions of use, the paradigm and generic preconceptions are jointly satisfied and determine the existence of an extension/anti-extension pair dividing the adjective’s comparison class into two mutually exclusive and jointly exhaustive subclasses. Sorites paradoxical occasions of use are irregular occasions (...) of use in which the paradigm and generic preconceptions are not jointly satisfied. In them, the relevant degree adjective lacks an extension, and utterances of sentences containing it appearing in sorites arguments do not have truth conditions. I also postulate a probable psychology of paradigm intuitions, used in a psychological explanation of the preference for solutions of the sorites paradox on which paradigm preconceptions retain their intuitive truth-values. (shrink)