Modalities Between Logic and Ontology: A Reassessment of Critiques ofModality

Abstract

The aim of this study is to discuss the implications of Frege, Kant, and Quine's critiques of modality for the relationship between logic and ontology. While Kant and Frege share the view that modalities do not affect the content of judgments and are only related to the epistemic stance toward judgments, the study emphasizes the differences between their perspectives. It is noted that Kant's motivation for excluding modality from judgments is ontologically driven, whereas Frege concerned with ensuring that modalities do not influence the truth value of propositions. Quine's critique, that quantified modal logic leads to Aristotelian essentialism, is examined alongside Kant's concerns, with both critiques sharing a common worry about the ontological problems that modalities might introduce. Furthermore, the development of modal logic is analyzed, showing that, contrary to Frege's claim, modalities are now considered within a semantic framework that determines truth values. It is also highlighted that modal logic serves as a valuable tool for addressing ontological problems and clarifying philosophical debates. The study concludes that the ontological concerns raised by Quine remain unresolved, as they extend beyond the boundaries of modal logic.