2019 Summer.Includes bibliographical references.Future contingent propositions have famously been a source of trouble for philosophers and logicians committed to any variety of indeterminism on which facts about the future are not yet fixed. One possible answer to the problem involves presupposition—namely, that propositions lack truth-value when other propositions that they presuppose are false. This paper explores the plausibility of such an answer, beginning with a brief discussion of the problem of future contingent propositions and presupposition. From there, an in-depth discussion of Free Logic lays the groundwork of logical tools for the project, exploring the motivation for Free Logic's development and examples of Free Logic semantics. Subsequently, this paper discusses the history and usefulness of events-based semantics in analyzing English sentences. Using the tools of events-based semantics and formal logic, this paper formally models this approach to sentences in English by defining a semantics which can capture both tense and aspect of such sentences and which allows for truth-valueless future contingent propositions while preserving logical truths like the law of excluded middle
