Index Nominum (Persons)

Historical geometers, astronomers, philosophers, translators, and philologists referenced in GEOMETOR Ptolemy.

Claudius Ptolemy (Κλαύδιος Πτολεμαῖος, c. 100 – c. 170 CE)

Alexandrian mathematician, astronomer, geometer, and cartographer; author of the Syntaxis Mathematica (Almagest), Planisphaerium, Geography, Harmonics, and Optics.

Syrus (Σύρος, fl. mid-2nd century CE)

Dedicatee of Ptolemy’s Almagest (ὦ Σύρε), Planisphaerium (Jesure via Arabic transcription), and Tetrabiblos.

Hipparchus of Nicaea (Ἵππαρχος ὁ Νικαεύς, c. 190 – c. 120 BCE)

Founder of Greek chord trigonometry (author of a lost 12-book treatise on chords in a circle) and quantitative solar/lunar theory; cited in Almagest I.12 for using Eratosthenes’ $\frac{11}{83}$ tropical ratio.

Menelaus of Alexandria (Μενέλαος ὁ Ἀλεξανδρεύς, c. 70 – 140 CE)

Author of the Sphaerica; formulated the intrinsic geometry of spherical triangles and the six-quantity spherical transversal theorem adapted in Almagest I.13.

Euclid of Alexandria (Εὐκλείδης, fl. c. 300 BCE)

Author of the Elements; provides the deductive foundation for every construction in Almagest I.10, I.13, and Planisphaerium §§1–4.

Apollonius of Perga (Ἀπολλώνιος ὁ Περγαῖος, c. 240 – c. 190 BCE)

Author of the Conics; proved in Conics I.5 that the subcontrary section of an oblique circular cone is a true circle.

Archimedes of Syracuse (Ἀρχιμήδης, c. 287 – 212 BCE)

Bounded $\pi$ between $3\frac{10}{71}$ and $3\frac{1}{7}$, an interval explicitly cited by Ptolemy (Almagest VI.7) in connection with $\pi \approx 3;8,30 = \frac{377}{120}$.

Eratosthenes of Cyrene (Ἐρατοσθένης, c. 276 – c. 194 BCE)

Alexandrian geographer and mathematician; measured the arc between the tropics as $\frac{11}{83}$ of the meridian circle (Almagest I.12).

Aristotle of Stagira (Ἀριστοτέλης, 384 – 322 BCE)

Cited in Almagest I.1 for dividing theoretical philosophy into physics, mathematics, and theology.

Theodosius of Bithynia (Θεοδόσιος, c. 160 – c. 90 BCE)

Author of the Sphaerica on the solid geometry of great and parallel circles on the sphere.

Maslama al-Majrītī (c. 950 – 1007 CE)

Andalusian astronomer in Córdoba who revised the Arabic recension of Ptolemy’s Planisphaerium and supplemented it with astrolabe chapters.

Hermann of Carinthia (Hermannus Secundus, c. 1100 – c. 1160 CE)

Translated Ptolemy’s Planisphaerium from Maslama’s Arabic recension into Latin at Toulouse on 1 June 1143.

Federico Commandino (1509 – 1575)

Renaissance editor and commentator on the Planisphaerium (Venice, 1558).

Nicolas B. Halma (1755 – 1828)

Editor and French translator of the Composition mathématique de Claude Ptolémée (Paris, 1813–1816).

Johan Ludvig Heiberg (1854 – 1928)

Danish philologist who edited the definitive Teubner texts of Ptolemy’s Syntaxis Mathematica (1898–1903) and Opera Astronomica Minora (1907).

Karl Manitius (1848 – 1921)

German translator of Heiberg’s Teubner text of the Almagest (Leipzig, 1912–1913).

Brahmagupta (c. 598 – c. 668 CE)

Indian mathematician whose rational cyclic quadrilateral theory complements Ptolemy’s Theorem.

John Casey (1820 – 1891)

Irish geometer who generalized Ptolemy’s Theorem to four bitangent circles (Casey’s Theorem).