Names, verbs, and sentences in ancient Greek philosophy

My purpose in this paper is to investigate some ancient conceptions of the composition and structure of sentences, focusing on Plato and Aristotle, with short forays into other authors and ages. I concern myself mainly with two mutually connected issues. First, both Plato and Aristotle hold that a minimal simple sentence consists of two expressions of different kinds, which they call onoma and rhema; I shall try to make clear the nature and purport of this distinction, which is controversial. Secondly (but partly at the same time), I try to trace the emergence and early development, from Plato to the Stoics, of the idea that a simple declarative sentence has a signification of its own over and above the signification of its parts.