In analytic philosophy, philosophy of language investigates the nature of language and the relations between language, language users, and the world. Investigations may include inquiry into the nature of meaning, intentionality, reference, the constitution of sentences, concepts, learning, and thought.
Gottlob Frege and Bertrand Russell were pivotal figures in analytic philosophy's "linguistic turn". These writers were followed by Ludwig Wittgenstein (Tractatus Logico-Philosophicus), the Vienna Circle, logical positivists, and Willard Van Orman Quine.
In the West, inquiry into language stretches back to the 5th century BC with Socrates, Plato, Aristotle, and the Stoics. Both in India and in Greece, linguistic speculation predates the emergence of grammatical traditions of systematic description of language, which emerged around the 5th century BC in India (see Yāska), and around the 3rd century BC in Greece (see Rhianus).
In the dialogue Cratylus, Plato considered the question of whether the names of things were determined by convention or by nature. He criticized conventionalism because it led to the bizarre consequence that anything can be conventionally denominated by any name. Hence, it cannot account for the correct or incorrect application of a name. He claimed that there was a natural correctness to names. To do this, he pointed out that compound words and phrases have a range of correctness. He also argued that primitive names had a natural correctness, because each phoneme represented basic ideas or sentiments. For example, for Plato the letter l and its sound represented the idea of softness. However, by the end of the Cratylus, he had admitted that some social conventions were also involved, and that there were faults in the idea that phonemes had individual meanings. Plato is often considered a proponent of extreme realism.
Aristotle interested himself with the issues of logic, categories, and meaning creation. He separated all things into categories of species and genus.