Was the greatest grammarian of antiquity truly a second-rate Stoic philosopher in disguise? For decades, scholars have seemed to believe so. This book shatters that consensus. By analyzing Apollonius Dyscolus’ core concepts—from proper names to conditionals—this book reveals a thinker far more eclectic and original than previously believed. Apollonius synthesized Stoic, Aristotelian, and Alexandrian ideas to create a unique grammatical project, allowing us to appreciate ancient Greek grammar as a sophisticated semantic theory in its own right—one that pragmatically deploys the philosophical lingua franca of the post-Hellenistic period to solve practical problems of language. This book is an essential reading for anyone seeking to understand how Western linguistic theory truly began.