Edgar Allan Poe is considered to be America's first significant literary critic or, at least, the first major writer in America to write seriously about criticism, about the theory of composition, and about the principles of creative art. He was also the first to set down a consistent set of principles about what he thought was acceptable in art and what should be essentially rejected in art.
As an editor of a magazine, Poe's views on literary criticism were influenced by the nature of the short works of art that would appeal to the magazine-reading public. But irrespective of his journalistic position, his critical views on the nature of what was and was not acceptable in a work of art have become famous and have had an enormous influence on subsequent writers.
Poe's major theories can be found (1) in the many reviews he wrote analyzing the writings of other authors; in this genre, his most famous review is entitled "Twice-Told Tales," a review of Nathaniel Hawthorne's short stories; (2) in the many letters, epistles, and applications he sent for jobs, or as answers he gave as an editor, among the more famous being the one entitled "Letter to B_____"; (3) in the various editorials he wrote for the magazines he was associated with, "Exordium" being one of the best examples of this type; (4) in the official critical articles he wrote, in which he attempted to present in a logical, coherent manner his critical views; as examples, "The Poetic Principle" and "The Philosophy of Composition" both contain the unified core and basis of Poe's critical theories, and these two essays alone suffice to give one a full understanding of Poe's critical views; (5) and, finally, in the critical principles that can be drawn from Poe's writings themselves, principles which he did not include in his critical dicta (dictums) per se.
