Necromancy, in its oldest and strictest sense, is the art of divination through the spirits of the dead, summoning them to reveal hidden knowledge, foretell the future, or lend their power to the operator. The word derives from the Greek nekros (dead) and manteia (divination). Its classic literary instances are ancient: in Homer's Odyssey, Odysseus travels to the edge of the world and, with blood-offerings, calls up the shades of the dead, including the prophet Tiresias, to learn his way home; in the Hebrew Bible, King Saul, on the eve of his death, has the medium of Endor raise the spirit of the prophet Samuel, an act the text presents as forbidden and ominous.
Indeed necromancy was widely prohibited and feared, consulting the dead is condemned in Israelite law and viewed with dread across many cultures, precisely because it was held to work. Over the medieval and early modern periods the word broadened, partly through confusion with the Latin nigromancia ("black" divination), to mean dark or forbidden magic in general, and the ritual raising of the dead became a staple of the grimoire tradition and of the demonized image of the sorcerer. Necromancy thus occupies a particular place among the divinatory arts: the one that seeks knowledge from those who have crossed into death, and the one most consistently marked, across traditions, as transgressive and dangerous.