In this thesis I study Frege’s views on truth, primarily as expressed in a late series of essays, Logical Investigations, and related unpublished works. The typical approach to Fregean exegesis is to interpret claims he makes and examine both their independent credibility and their consistency with his broader thought. Although this is part of my aim, primarily I seek to trace a pedagogical journey of thought that, I show, he presents in these works. By doing this, his claims regarding truth are presented, first and foremost, within a dialectical context. And I endeavour to show that, by maintaining that context in mind, many of the puzzles that surround his claims can be resolved in a coherent and satisfying manner.

In tracing this movement, I begin where Frege begins in Thoughts, the first essay in the series. Here he states that logic is a science, but a special one. Like all sciences, logic seeks to discover truths, but unlike other sciences, logic also studies truth as its subject matter. This, I argue, means logic is concerned with truth at both the epistemic and ontological level. Once this broad conception is accepted as the first principle he presents it to be, many of the other claims he makes regarding truth follow quite naturally. These claims include: that truth is indefinable, that the predicate ‘is true’ sometimes has a sense that makes no contribution to the thought expressed by the sentence it occurs in, that truth is indicated by assertoric force, and that truth is an object rather than a property. Other less explicit claims, I argue, can also be teased from his writings: that thoughts are epistemic units, that the structure of a thought is multiply analysable, and that truth is ultimately ineffable.