David Lewis’s counterpart theory is often seen as involving a radical departure from the standard, Kripke-style semantics for modal logic, suggesting that we are dealing with deeply divergent accounts of our modal talk. However, CT captures but one version of the relevant semantic intuition, and does so on the basis of metaphysical assumptions that are ostensibly discretionary. Just as ML can be translated into a language that quantifies explicitly over worlds, CT may be formulated as a semantic theory in which (...) world quantification is purely metalinguistic. And just as Kripke-style semantics is formally compatible with the doctrine of world-boundedness, a counterpart-based semantics may in principle allow for cases of trans-world identity. In fact, one may welcome a framework that is general enough to include both Lewis’s counterpart-based account and Kripke’s identity-based account as distinguished special cases. There are several ways of doing so. The purpose of this paper is to outline a fully general option and to illustrate its philosophical significance, showing how the large variety of intermediate relations that lie between Lewisian counterparthood and Kripkean identity yield a corresponding variety of modal theories that would otherwise remain uncharted. (shrink)

Special issue: "Reflecting on the Legacy of C.I. Lewis: Contemporary and Historical Perspectives on Modal Logic".

It is a truth universally acknowledged that a claim of metaphysical modality, in possession of good alethic standing, must be in want of an essentialist foundation. Or at least so say the advocates of thereductive-essence-firstview, according to which all modality is to be reductively defined in terms of essence. Here, I contest this bit of current wisdom. In particular, I offer two puzzles—one concerning the essences of non-compossible, complementary entities, and a second involving entities whose essences are modally ‘loaded’—that together (...) strongly call into question the possibility of reducing modality to essence. (shrink)

Se afirma que los enunciados necesarios a posteriori, propuestos por S. Kripke, exigen una comprensión débil de la necesidad; esto quiere decir: a) existencia contingente del designatum y b) dependencia racionalista en principios lógicos a priori, particularmente los de diferencia y de identidad. La principal consecuencia es que los enunciados necesarios a posteriori corresponden a instancias de dichos principios lógicos. Contrario al racionalismo, esto no exige que dichos enunciados sean a priori, pues su justificación requiere información empírica. Finalmente, se defiende (...) que la distinción entre denotación y designación permite sostener que la necesidad débil se aplica a las instancias de la clase, y no a esta, con lo que se evita el indeterminismo referencial. The article states that a posteriori necessary sentences as proposed by S. Kripke require a weak understanding of necessity. This means: a) contingent existence of designatum, and b) rationalist dependence on a priori logical principles, particularly those of difference and identity. The main consequence is that a posteriori necessary sentences correspond to instances of these logical principles. Contrary to rationalism, this does not require that these be a priori sentences, given that their justification requires empirical information. Finally, the article argues that the distinction between denotation and designation supports the idea that weak necessity applies to instances of the class, and cannot be applied to the class itself, thus avoiding referential indeterminism. (shrink)