Abstract

What makes a logical truth logical? Three types of theories are considered--one based on meaning relations, another on modality, and one on generality. The first two disengage logical truth from the actual world: the first denies the world a role in grounding the truth of a logical truth, and the second regards actual truth as too plain to support logicality. In contrast, the third treats logical truth as a special variety of actual truth grounded in the world. ;The analyticity theory of logical truth claims that logical truths are true solely in virtue of meaning relations. Chapter One criticizes the theory for denying that any true sentence is made true by how things are with the world. For in doing so, the theory assigns different semantics to logical and non-logical truths with the same syntactic structure. Also, it contradicts the intuition that a sentence is true because the world is as the sentence claims; distinguishing between two senses of "true independent of the world" defuses the opposing intuition in standard cases. ;According to traditional lore, all logical truths are necessary. Recently, several philosophers have also presumed pervasive acceptance that necessity is essential to the very notion of logical truth. My second chapter proves this false: a survey reveals that the most popular theories of logical truth do not appeal to necessity. But once we omit necessity from our account of logical truth, we should not presume logical truth's extension is subsumed by that of necessary truth. ;We move then to treating logical truth as actual truth grounded in the world, but of a very general nature. Chapter Three distinguishes three notions of generality associated with logic, calling specific attention to a suggestion gleaned from Russell--logic concerns the actual world's more abstract and generic features. The fourth chapter considers what the permutation invariant truth of logical truths can reveal, motivating a version of Russell's suggestion: a logical truth is one whose truth is secured by generic features of objects and properties--features objects and properties have qua members of the genera object and property