Agnes Nitt

A major subset of the Discworld novels of Terry Pratchett involves the witches of Lancre. They are closely based on witches in British folklore and a slightly tongue-in-cheek reinterpretation of the Triple Goddess.

Witch magic is very different from the wizard magic taught in the Unseen University, and consists largely of finding the right lever that makes everything else work. Witches rarely do any magic, in fact, relying more on common sense, hard work, and a peculiar brand of psychology known as headology. This can be taken very far - a witch's way of magically setting fire to a log of wood consists of staring at the log until it burns up from pure embarrassment. As a result, it is less energy-intensive, which means that a witch can do more than a technically equally powerful wizard. The same zen-like knowledge that gives them this ability generally discourages them from making a big deal about it, beyond refusing to take wizards seriously. Headology is more commonly used on people, like the placebo effect. Witches unironically acting with melodrama, of which cackling is an early sign, is often an indication of "going to the bad" and becoming a stereotypically wicked witch.

Another later addition to witch skills, established in Maskerade, but first named in the Aching books, is First Sight—seeing what's really there instead of what you hope to, expect to, or what others see—and Second Thoughts—thinking about the way you're thinking.

Unlike wizard magic, which is taught en masse, witch magic is taught on a one-to-one basis by older witches to apprentices. Although magical talent tends to run in families, witches do not teach their daughters, feeling that this would cause a sort of magical inbreeding.

Discworld Voodoo is considered to be an aspect of witch magic, combined with a sort of do-it-yourself religion, relying heavily on the power of belief. The most powerful Discworld voodoo-women can deliberately create moderately powerful gods for a specific purpose.

Generally speaking, witches are women and wizards are men. Despite the opinions of wizards and witches on this subject (that systemization comes easier to men and intuition comes easier to women), there appears to be no reason for this beyond cultural bias. There has only ever been one female wizard on the main Discworld continent, as described in the events of Equal Rites. The island of Krull on the very Rim of the Disc does not mind female wizards but no one from the Circle Sea would ever admit they exist.

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