A familiar, in many Western European folklore is a spirit that would help warlocks and scholars in their practice of magic. Familiars appear in many forms, often as an animal, but sometimes as a human or humanoid figure.
When they serve a warlock or witchs, they were often thought to be
malevolent while when serving a scholar, they were often thought of as
benevolent (although there is some ambiguity in both cases). The former were often classified as demons, while the latter were more commonly classified as fairies. The main purpose of a familiar is to serve the witch (or young witch), providing protection while she mastered her new powers.
The best known of these familiar geniuses is the daimon (δαίμων) of Socrates, but many researchers for centuries, refer to entities of this type, sometimes under the name of good genius or guardian spirit.
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