Calling a Spirit to Visible Appearance

In the vocabulary of ceremonial magic, evocation is the operation of summoning a spirit, an angel, demon, planetary intelligence or other entity, to appear in an external space, classically within a triangle set outside the protective circle in which the magician stands. It descends directly from the grimoire tradition of medieval and early modern Europe, the handbooks of ritual instruction such as the Key of Solomon and the Lesser Key (Lemegeton), which prescribe the names, seals, circles and adjurations by which named spirits were to be constrained and questioned.

The magician's own safety was held to depend on the integrity of the circle and the correctness of the words. The later magical orders, above all the Golden Dawn, and figures such as Aleister Crowley inherited and reworked these procedures, and historians such as Owen Davies have traced how the grimoires carried this practice from clerical circles into the modern occult revival.