What Is Sussior Talking About When We're Looking at Language?

Sussior: There's no such thing as private language. It cannot function. What is society without language? So it's only through this universality that language means anything at all. The diachronic study of language says basically stop the system of language in that period of time. We're not talking about how it develops in history. Instead he's dealing with the synchronic axis in terms of language. He's dealing with language.