John of Seville

John of Seville, in Latin Johannes or Ioannes Hispalensis, was a Latin translator of the twelfth century. The Encyclopaedia of Islam has no article on him. He appears as the translator in the entries on the Arabic authors he rendered, and this record gathers those passages. ^{1 2} The articles read give no birth or death date, no account of his life and no statement of where he worked; they date his translations from 1130 to 1153. ^{1 3}

The article on Abu Ma'shar says his Great Introduction to astrology, in eight books, was twice translated into Latin, first in 1130 by Johannes Hispalensis and then in 1150 by Hermannus Secundus, or the German. It calls the work very influential in Christian Europe and notes that it contains the theory of tides, from which, the article says, medieval Europe learned the laws of ebb and flow. ¹ Two further works of Abu Ma'shar are also credited to John: the treatise on the revolutions of the years of nativities, rendered as De magnis coniunctionibus, and a short summary of it rendered as Flores astrologiae. ¹

The article on astrological decrees adds that Abu Ma'shar's treatise on the choice of propitious times was probably translated as Flores de electionibus by John of Seville. ⁴ The same article says Ahmad al-Imrani, known to Europeans as Haly Imrani, wrote a book on choosing times that was translated into Latin by Plato of Tivoli together with Abraham b. Hiyya, known as Savasorda, and by John of Seville as Regule de electionibus. ⁴ It also records that a summary titled Kitab al-Mawalid, composed by Umar ibn al-Farrukhan from the writings of Hermes, Dorotheus, Ptolemy and others, was translated into Latin by Johannes Hispalensis. ⁵

The article on al-Kabisi, the astrologer of the Hamdanid court, says a Latin version of his introduction to astrology was made by Ioannes Hispalensis in 1144, that a French translation followed in 1362, and that Ioannes de Saxonia commented on the Latin at Paris in 1331. It also notes a De planetarum coniunctionibus attributed to Alchabitius in John's Latin translation, which the article doubts is by al-Kabisi at all. ^{6 7}

For Abu Ali al-Khayyat, the article says two Latin translations were made of his Kitab al-Mawalid, one by Plato of Tivoli at Barcelona in 1136 and the other by John of Seville in 1153; John's was printed at Nuremberg under the title Albohali de iudiciis nativitatum liber unus. ³ The article on Masha'allah says that his letter on eclipses survives in Latin in a translation by John of Seville, printed at Basle in 1551, as well as in a Hebrew version by Abraham 'Ezra. ⁸

Al-Farghani's main astronomical work was translated into Latin by John of Seville and by Gerard of Cremona. John's version was printed at Ferrara in 1493, at Nuremberg in 1537, in Paris in 1546 and, edited by F. J. Carmody, at Berkeley in 1943. ⁹ A bibliography in the article on the lunar mansions gives the year of John's translation as 1135. ¹⁰

The article on Ibn al-Saffar, a pupil of Maslama al-Majriti who died at Denia in 426/1035, records two Latin versions of his treatise on the astrolabe: one by Johannes Hispalensis, which appears under the name of Maslama al-Majriti, and one by Plato of Tivoli, which names Ibn al-Saffar. Millas Vallicrosa argued that Maslama's name was substituted by confusion because both men shared the kunya Abu al-Qasim. ¹¹

The article on al-Khwarizmi says John of Seville made known a Latin version of an adaptation, made either by himself or by some Muslim author, of al-Khwarizmi's Arithmetic, which is lost in Arabic; John's work is called Liber alghoarismi de pratica arismetrice. ² The article on arithmetic confirms that the Liber algorismi of Ioannis Hispalensis was published by Boncompagni, and describes how the book explains the decimal place-value system. ¹² The al-Khwarizmi article adds that rules for operating with sexagesimal fractions entered university teaching quickly, through an adaptation in De numero indorum and above all through John of Seville. ¹³ The same article says the Latin Algebra was translated at almost the same time by Robert of Chester, whom the museum records as Robert of Ketton. ²

In the article on palm-reading, al-Kaff, a pseudo-Aristotelian Ciromantia is said to have been translated by John of Seville and Adelard, with the author's own question marks about both the source language and whether this is Adelard of Bath. ¹⁴

The articles read do not say where John worked, who commissioned him, or whether the Johannes Hispalensis of the different translations is one person; they speak of a single translator throughout. The museum follows them and does not add a biography. Dates of the translations differ slightly in places, for example 1130 for Abu Ma'shar and 1135 for al-Farghani, and each is given as the article states it.