In 'On the Sublime,' traditionally attributed to Longinus, the author explores what constitutes good writing, emphasizing the concept of the sublime—a profound emotional state often evoked by nature's power. Longinus identifies five sources of sublimity: strength of thought, inspired emotion, effective use of figures of speech, notable language, and a dignified overall effect, while distinguishing true sublime writing from false sublimity created by lack of genuine passion and poor technique. This treatise critiques both literary excellence and the pitfalls that can detract from authentic expression.