  Schopenhauer uses an analogy from chemistry to describe the aim of the true poet.  Just as the chemist combines various liquids in order to distill out precisely the solid precipitates she wants, the aim of the poet is to use abstract concepts but to restrict the generality of these concepts (by the use of epithets and other vivid descriptors) to “precipitate” out precise images in the minds of her readers, listeners, or spectators (WWR I, 269). The generality of its material—the concept—allows poetry to express a vast number of Ideas.  It can range over all of nature, but is especially apt to express the Idea of humanity in their actions, thoughts, and feelings.  And in expressing this Idea in its multiplicity, poetry has a distinct advantage over history, according to Schopenhauer (here following Aristotle), for poetry is not beholden to actual events and people, but rather to what is possible or probable and thus may better capture what is truly significant in human existence. (For a comparison between Schopenhauer and Early German Romantic thinkers on poetry, see Millán 2017).