Read the excerpt from "A Defence of Poetry.” All the authors of revolutions in opinion are not only necessarily poets as they are inventors, nor even as their words unveil the permanent analogy of things by images which participate in the life of truth; but as their periods are harmonious and rhythmical, and contain in themselves the elements of verse; being the echo of the eternal music. Nor are those supreme poets, who have employed traditional forms of rhythm on account of the form and action of their subjects, less capable of perceiving and teaching the truth of things, than those who have omitted that form. In this excerpt, Shelley compares poets to because their words create images that reveal truths about life.