The Ganitasara Of Thakkara Phera

Summary

This article introduces the mathematical work Gaṇitasāra authored by Thakkura Pheru, a Jain polymath and treasury official in the court of Delhi Sultans during the early 14th century. Belonging to the Śrīmālī Jain caste, Pheru wrote six scientific treatises—Gaṇitasāra (arithmetic) being one of the most practical. Key points include: i) Pheru served under Sultans Alauddin Khalji to Ghiyāsuddin Tughluq, writing texts on topics like gemology (Ratnaparīkṣā), architecture (Vāstusāra), and money exchange (Dravyaparīkṣā). ii) Gaṇitasāra, composed around 1318 CE, is known for applying arithmetic to everyday professions: construction, textiles, trade, and agriculture. iii) The text provides rules for solid geometry to calculate construction volumes, e.g., for domes, spiral staircases, and fluted towers (likely inspired by Delhi’s Qutb Minar). iv) It also includes tables for cloth cutting, shrinkage, tent sizing, and agricultural yields, showing adaptation of arithmetic to diverse practical needs. v) Pheru introduces one of the first known Indian methods for converting Vikrama Samvat to Hijri calendar dates.