This paper applies to ancient Greece an approach developed by Pierre Rosanvallon: the integration of philosophical texts with the most everyday documents to better grasp a society’s understanding of its political life. For the ancient polis, this means focusing on the more pro-saic evidence offered by cities’ inscriptions, especially their collective decisions published on stone. It is used here to consider the changing ideas about the nature of political and private life—and especially the space between them. In a very influential model, Classical Athenian democrats and philosophers tended to insist on a sharp binary distinction between public/ political life and private life, leaving little room for a notion of an intermediate third space of polis life, similar to a “social sphere” or “civil society.” This pattern remained dominant in the Hellenistic and Roman periods, but, especially after c. 150 BCE, some Greek citizens and intellectuals developed, above all in inscriptions, a much more explicit, complex, and subtle notion of “social life” as something between politics and private life. The article concludes by asking what the different ancient concepts discussed can contribute to current historiographical debates about the nature of the Greek city after c. 150 BCE, especially when it comes to moving beyond the traditional picture of “depoliticization.” It also calls into question the orthodox narrative of the development of ideas of “the social” over many centuries up to the present.