Abraham Bar Hiyya - Original Works

Original Works

Abraham bar Ḥiyya, together with Abraham ibn Ezra, occupies an important place in the history of Jewish science. He was, indeed, one of the most important figures in the scientific movement which made the Jews of Provence, Spain, and Italy the intermediaries between Mohammedan science and the Christian world. He aided this movement not only by original works, but also by translations and by acting as interpreter for another great translator, the celebrated Plato of Tivoli. Steinschneider has also shown that his original works were written in Hebrew and not, as some have thought, in Arabic. These original works are:

• יסודי התבונה ומגדל האמונה ("The Foundations of Understanding and the Tower of Faith"), an encyclopedic work, which is said to treat of arithmetic, geometry, optics, astronomy, and music. Unfortunately only a few short fragments of this work have been preserved (MSS. De Rossi Library, No. 1170; Berlin Library, No. 244; Munich Library, No. 36; and, under a false title, MSS. Bodleian, 1268, No. 7).

• חבור המשיחה והתשבורת ("Treatise on Geometry"), probably intended to be a part of the preceding work. This is the celebrated geometry translated in 1145 by Plato of Tivoli, under the title Liber Embadorum (see Boncompagni in Atti dell' Accademia dei Lincei, 1851, iv. 275; Hebr. Bibl. vii. 84; Serapeum, 1858, p. 34; it was edited by Steinschneider in the Publications of the Meḳiẓe Nirdamim, 1895, vol. xi.).

• צורת הארץ ("Form of the Earth"), an astronomical work on the formation of the heavens and the earth, which was to have been followed by a second part on the course of the stars (see No. 4). A portion was translated into Latin by Sebastian Münster and by Erasmus Oswald Schreckenfuchs. It appears also that complete translations into Latin and French were made (Steinschneider, Abraham Judæus, 12). MS. 2033 in the Bodleian Library at Oxford contains a copy with a commentary, apparently by Ḥayyim Lisker.

• חשבון מהלכות הכוכבים ("Calculation of the Courses of the Stars"), the sequel to the preceding work, which is found sometimes in manuscripts with the notes of Abraham ibn Ezra (MS. 37 of Leyden, according to the catalogue of Steinschneider, p. 147; MS. 203 of Rome, Bibl. Casanatense, according to the catalogue of Sacerdote).

• לוחות or לוחות הנשיא ("Tables" or "Tables of the Prince"), astronomical tables, called also Tables of Al-Battani, because the author followed the Arabic astronomer of that name (see Battani). Several manuscripts of this work contain notes by Abraham ibn Ezra, and this fact has occasioned some confusion between the "Tables" of these two authors.

• ספר העבור ("Book of Intercalation"). This work was published in 1851, in London, by Filipowski. It is the oldest Hebrew work treating of the calculation of the Hebrew calendar.

• הגיון הנפש ("Meditation of the Soul"), an ethical work upon a rationalistic religious basis. It was published in 1860 by Freimann, with a biography of the author (by the editor), a list of his works, and a learned introduction by Rapoport.

• מגלת המגלה ("Scroll of the Revealer"), a controversial work, in defense of the theory that the Messiah would appear in the year 5118 (1358; MS. Munich, 103, ).

• An apologetic epistle addressed to Judah ben Barzilai al-Barzeloni.