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Goetia refers to a practice which includes the invocation of angels or the evocation of demons, and usage of the term in English largely derives from the 17th century grimoire The Lesser Key of Solomon, which features an Ars Goetia as its first section. It contains descriptions of the evocation of seventy-two demons, famously edited by Aleister Crowley in 1904 as The Book of the Goetia of Solomon the King.
Goetic Theurgy, another practice described in the Lesser Key of Solomon, is similar to the book’s description of Goetia, but is used to invoke aerial spirits.