The narrator remarks about Usher’s paintings that “by the utter simplicity, by the nakedness of his designs, he arrested and overawed attention. If ever mortal painted an idea, that mortal was Roderick Usher.” Left unsaid is what, exactly, that idea might have been. Usher is someone “from which darkness, as if an inherent positive quality, poured forth upon all objects of the moral and physical universe in one unceasing radiation of gloom,” and it’s fair to say that Usher’s art is a representation of that “gloom.” Yet the reason why his art should inspire gloom is unclear: the narrator remarks about his guitar music that “an excited and highly distempered ideality threw a sulphureous lustre over all,” meaning that there is perhaps some essential idea or concept contained in his art that gives it this quality. The painting that the narrator describes, of the vault deep underground, with no entrance or exit, brightly lit but with no visible source of illumination, is a case in point. What is this room, and what is there about the image that makes it so ghastly, except its impossibility: it is like a painting of the inside of a crypt. Usher makes his art as a way of articulating the nameless sense of foreboding that consumes him. Like much of Poe’s fiction, it is an assertion of the power of emotion. I don’t think it’s right to say his art is irrational; it’s more like Usher has discovered some hidden principle at work in the world, that turns everything to melancholy or the macabre.
Roderick Usher follows in the footsteps of generations of Ushers and their artistic temperament. Roderick paints, plays music, and writes poetry and prose.
At the time of the narrator's visit, he observes Roderick's paintings, and notices that they are so abstract in form that they cannot be described.
The only music that Roderick will pale is that of his guitar and other stringed instruments. He tells the narrator that is all he can tolerate.
The poem that the narrator discusses is that of a mythical palace that is inhabited by Thought. It is a peaceful and pure place until an "evil thing" causes Thought to become melancholy and the tale ends with impending doom.
All of Roderick's artful endeavors are now much like Roderick himself, melancholy, dark, and with a sense of foreboding.