Speculum literature

The medieval genre of speculum literature, popular from the twelfth through the sixteenth centuries, was inspired by the urge to encompass encyclopedic knowledge within a single work. The modern equivalent is a summary survey, in the sense of a survey article in a scholarly journal that summarizes a field of research. The speculum image, of the mirror that reflects far and wide, was drawn from the magical mirror that was supposed to belong among the treasures of legendary Prester John somewhere in the East; through it every province could be seen:

"Before our palace stands a mirror, the ascent to which consists of five and twenty steps of porpyry and serpentine ... This mirror is guarded day and night by three thousand men. We look therein and behold all that is taking place in every province and region subject to our sceptre."

In the genre "Speculum of Princes", the prince's realms were surveyed and his duties laid out. Other specula offered mirrors of history, doctrine, or morals.

A number of medieval book titles include the word speculum:

Ormulum, written by a certain Orm in Central England, bears an indirect reference to speculum and may be translated as "Orm's Mirror". It is universal in contents in that it contains the appropriate homiletic materials throughout the Church calendar.

In English mirror appears in, among many other works, the Myrrour of the Worlde (1490), one of the first illustrated books printed in English, by William Caxton (a translation of L'image du Monde, an overview of the sciences), the perennially-republished A Mirror for Magistrates (1559), and The Miroir or Glasse of the Synneful Soul, a manuscript translation from the French by the young Queen Elizabeth I of England. The Mirror of Simple Souls is a modern English translation of a similar French work. The word 'speculum' was rendered into English as 'mirror or glass'.

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