The philosophy of language investigates the fundamental nature of language, exploring its connection to users and the world, and delving into concepts like meaning, reference, and thought. This field saw a pivotal "linguistic turn" in analytic philosophy, largely driven by figures like Gottlob Frege and Bertrand Russell, followed by Ludwig Wittgenstein and Willard Van Orman Quine. Ancient philosophers, dating back to the 5th century BC, also laid foundations: Plato debated whether names are determined by convention or nature in his Cratylus, while Aristotle examined the creation of meaning through categories, contributing to theories of nominalism and realism. Later, the Stoics developed a sophisticated analysis of grammar and the concept of lektón (meaning), and medieval philosophers, including William of Ockham, regarded logic as a "science of language" (scientia sermocinalis), foreshadowing many modern linguistic inquiries.