This document summarizes Longinus's treatise "On the Sublime", which analyzes the concept of sublimity in language and its ability to elevate discourse. It defines sublimity as consisting of lofty language that sways readers through grandeur of thought, treatment of passions, figures of speech and thought, dignified expression through word choice and metaphor, and majestic structure. While sublimity cannot be innate, it can be developed through instruction and reason. The document outlines Longinus's influential views on sublimity that shaped Romantic literature and criticism.