Brazen head

A brazen head, brass, or bronze head was a legendary automaton in the early modern period whose ownership was ascribed to late medieval scholars who had developed a reputation as wizards, such as Roger Bacon. Made of brass or bronze, the male head was variously mechanical or magical. Like Odin's head of Mimir in Norse paganism, it was reputed to be able to correctly answer any question put to it, although it was sometimes restricted to "yes" or "no" answers. Thomas Browne considered them to be misunderstanding of the scholars' alchemical work, while Borlik argues that they came to serve as "a metonymy for the hubris of Renaissance intellectuals and artists".

Medieval Arabic poetry has references to brazen horses that could fly swiftly enough to traverse the world in less than a day, disappearing and reappearing upon command, and describes the Trojan horse as having been one of their ilk. It is likely that these accounts had their origin in allegorical treatments of alchemy and in early machines whose owners pretended to have given them life or speech. They may also have found inspiration in the Greek legends concerning Talos, the brass guardian of Minoan Crete.

The first account of a talking head used to give its owner answers to his questions appears in William of Malmesbury's c. 1125 History of the English Kings, in a passage where he collects various rumors surrounding the polymath Pope Sylvester II, who was said to have traveled to al-Andalus and stolen a tome of secret knowledge, whose owner he was only able to escape through demonic assistance. He was said to have cast the head of a statue using his knowledge of astrology. It would not speak until spoken to, but then answered any yes/no question put to it.

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