A brazen head, brass, or bronze head was a legendary automaton in the early modern period whose ownership was ascribed to late medieval scholars, such as Roger Bacon, who had developed a reputation as wizards. Made of brass or bronze, the male head was variously mechanical or magical. Like Odin's head of Mimir in Norse paganism,^{[n 1]} it was reputed to be able to correctly answer any question put to it, although it was sometimes restricted to "yes" or "no" answers. In the seventeenth century, Thomas Browne considered them to be misunderstanding of the scholars' alchemical work,^[1] while in modern times, Borlik argues that they came to serve as "a metonymy for the hubris of Renaissance intellectuals and artists".^[2] Idries Shah devotes a chapter of his book The Sufis to providing an interpretation of this "head of wisdom" as well as the phrase making a head, stating that at its source the head "is none other than the symbol of the [Sufic] completed man."^[3]

Chaucer's "The Squire's Tale" depicts a moving brazen horse among the gifts from an Arab and an Indian king to Cambuscan, and compares it to the Trojan horse.^[4] It is likely that these accounts had their origin in allegorical treatments of alchemy^[1] and in early machines whose owners pretended to have given them life or speech.^[4] They may also have found inspiration in the Greek legends concerning Talos, the brass guardian of Minoan Crete.^[5]

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.^{[6][7][n 2]} 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.^[6]

The Roman poet Virgil, in his medieval role as a sorcerer, was credited with creating his own oracular head in Gautier de Metz's c. 1245 Image of the World (French: Image du Monde).^[2] The 1319 Renard le Contrefait retold the story and may have been the first to specify that the head was made of brass.^[2]

The heads were then ascribed to several of the major figures of the 12th- and 13th-century Renaissance, who introduced Europe to Arabian editions of Aristotelian logic and science, as well as the Muslims' own work on mathematics, optics, and astronomy. These included Robert Grosseteste,^[11] Albertus Magnus, and—most famously^[12]—Roger Bacon.^[13] Grosseteste was said to have constructed "an hed of bras to... make it for to telle of suche thinges as befelle" over the course of seven years but then lost it through 30 seconds' neglect.^[11] Its relics were supposedly held in a vault under Lincoln College.^[14] Reports that Albertus Magnus had a head with a human voice and breath and "a certain reasoning process" bestowed by a cacodemon^[15] eventually gave way to stories that he had built an entire automaton who was so overly talkative that his student Thomas Aquinas destroyed it for continually interrupting his train of thought.^[4][14] Bacon, with the help of a Friar Bungy^[14] or Bungay,^[16] was said to have spent seven years building one of the devices in order to discover whether it would be possible to render Britain impregnable by ringing it with a wall of brass.^{[14][n 3]} They only succeeded in their work once they compelled the assistance of a demon.^[16] Like Grosseteste before them, however, they were said to have missed the decisive moment, either from forgetfulness^[14] or exhaustion.^[16] Having missed it, the head either collapsed or exploded^[16] or was scrapped as useless.^[14]

Other people reputed to have a brazen head include Boethius, Faust,^[13] Arnaldus de Villa Nova,^[19] Stephen of Tours,^[20] and Enrique de Villena.^[21] A brazen head also appears in the surviving accounts of the Carolingian Valentine and Nameless,^[22] where it reveals the pair's royal origin in a necromancer's lair in Clarimond Castle;^[4] despite the age of the base story, however, the earliest surviving copies date to the 15th century. It is thought to have been the basis for a lost Elizabethan drama.^[2]

Hero of Alexandria wrote two books, the Pneumatica and Automata, about devices powered by steam, water, or air. These books were known to medieval Islamic science, and reappeared in Europe during the 12th- and 13th-century Renaissance.

The talking "Skull of Balsamo" was a mechanical illusion of the Viennese magician Joseffy. The skull was made of painted copper inset with real human teeth, answering questions by turning or clicking its lower jaw.^[23]

The Brazen Head pub in Dublin, established in 1198 and over 800 years old, is the second oldest pub in Ireland. There is also a Brazen Head pub in Limerick.

Additionally, there are bars named The Brazen Head in Brooklyn, New York; in Toronto, Ontario, Canada; and pubs in Omaha, Nebraska; in Marylebone in London; in Glasgow; in Bloemfontein, South Africa; and in Napier, New Zealand. There is a Brazen Head Inn in Mingo in West Virginia and San Francisco.

• List of fictional robots and androids
• Zoltar (fortune-teller robot)
• Teraphim