Sharp Boundaries in a Fuzzy World: Why Epistemicism Survives the Sorites

The sorites paradox reveals the tension between the vagueness of natural language and the principles of classical logic. It has sparked significant contemporary debates in logical philosophy. Traditional binary logic struggles to face the challenges posed by ambiguous predicates. Researchers have proposed various solutions, such as degree theory, supervaluationism, and many-valued logic, but all face interpretive limitations. This paper systematically examines the logical structure of the sorites paradox and focuses on Williamsons epistemicist theory. Epistemicism maintains that ambiguous predicates possess objective and precise boundaries, though these lie beyond human cognitive reach and remain unknowable. By introducing the notion of unknowability, this theory preserves the validity of classical logic while offering a unique framework for addressing vagueness. This paper analyzes the mathematical logic foundations of epistemicism and its applied value in natural language analysis, legal reasoning, and ethical judgment, highlighting its advantages in theoretical simplicity, interpretive consistency, and intuitive rationality. Although epistemicism still faces challenges such as boundary arbitrariness and higher-order fuzziness, it has significant importance in resolving the sorites paradox and promoting interdiscipcolinary exchange. Finally, this paper proposes that future studies on epistemicism should focus on these three aspects: formal expansion, comparative studies, and interdisciplinary integration.