Faced with the growing cultural impact of science, the Romantic poets tended to consider scientific analysis and reasoning as a disfigurement of the beauty of the natural world. Percy B. Shelley used this very tendency to serve poetic ends. For him, optics and astronomy stand for the limitations of man’s point of view and for his inability to apprehend absolute beauty. In Epipsychidion (1821), Shelley refers to astronomy, because it has established that only a feeble glimmer of stellar light actually reaches the Earth. In The Triumph of Life (1822), the glimmer is then confined to the obscure tissues and humours of the eye, where, in accordance with Newton’s optics, it is broken up by refraction. Shelley even chooses the fate of light when it comes into contact with opaque bodies as a metaphor for the writing process. In Epipsychidion, the poem appears as a substitute light eclipsing the radiance it is trying to reveal, while in The Triumph of Life, Shelley resorts to Thomas Young’s wave theory of light to question the workings of poetic reference, turning his poem into an interference field.