1561-1613

German Mathematician

Bartholomeo Pitiscus is known primarily for his coining of the term "trigonometry," which appeared in the title of his Trigonometria: sive de solutione triangulorum tractatus brevis et perspicuus (1595). The latter, which used all six trigonometric functions, became a highly respected mathematical text, and was translated into several languages.

Pitiscus was born on August 24, 1561, in Grünberg, Silesia, which is now the town of Zielona Góra, Poland. At Zerbst and later Heidelberg, he studied theology under Calvinist teachers, and throughout his life remained a committed proponent of Calvinism, an early Protestant sect that placed an emphasis on predestination and the work ethic.

In 1584, Pitiscus received an appointment to tutor 10-year-old Friedrich der Aufichtige, or Frederick IV, elector Palatine of the Rhine. The boy was destined to hold an important position within the nobility of the Holy Roman Empire; thus for Pitiscus, who later became his court chaplain, the position was a secure one.

Trigonometria, first published in 1595, consisted of three sections. The first addressed plane and spherical geometry, while the second contained tables for the six trigonometric functions. (Pitiscus carried these to five or even six decimal places.) The third section consisted of assorted problems in areas ranging from astronomy to geodesy. Revised editions followed in 1600, 1609, and 1612, along with translations into English in 1614 and French in 1619.

Pitiscus remained a staunch defender of Calvinism, and his influence expanded when Frederick took power after his uncle, John Casimir, died in 1592. Frederick ruled until his death in 1610, and Pitiscus followed his patron by three years, dying on July 2, 1613, in Heidelberg.