Phantasmata is an orchestral triptych by the American composer Christopher Rouse. The title is derived from the works of the occultist Paracelsus, who described phantasmata as "hallucinations created by thought." Rouse originally composed the second movement "The Infernal Machine" as a stand-alone piece in 1981, though he later elected to make it the second part of a larger work. Phantasmata was commissioned in full by the St. Louis Symphony and a fellowship grant from the National Endowment for the Arts and completed March 22, 1985.