A History of the Kerala School of Hindu Astronomy (in Perspective) c10.s7.1

c10.s7.1

Jyeṣṭhadeva, this name being, most probably, the Sanskritised form of his personal name in the local language, has the distinction of being the author of the popular *Yuktibhāṣā*¹ or *Gaṇitanyāyasaṅgraha*,² which forms an elaborate and systematic exposition of the rationale of mathematics in its Pt. I and of astronomy in its Pt. II. The Sanskrit version of this work, known as *Gaṇitayuktibhāṣā*, is also, in all probability, his work. An old astronomical document informs that he was the pupil of Dāmodara of Vaṭaśreṇi and was a member of the Paraṅnoṭṭu family³ of the Ālattūr village in South Malabar.⁴ Nilakaṇṭha Somayāji, whose *Tantrasaṅgraha* he mentions towards the beginning of his work, was his respected elder. He himself was the teacher of Acyuta Piṣāraṭi who mentions him in reverential terms at the close of his *Uparāgakriyākrama* (A.D. 1592). M. Whish records a tradition that the author of the *Yuktibhāṣā* was the author also of a *Dṛkkaraṇa*⁵ The *Dṛkkaraṇa* in question, which is now available in a single manuscript, is a comprehensive metrical treatise in Malayalam on astronomy. It does not give anywhere the name of its author, but gives in its last verse, its date of composition in the words *kolambe barhiśūnau* (M.E. 783 = A.D. 1608). In view of this date and the mention of the tradition recorded by Whish, it is quite possible that this is a work of Jyeṣṭhadeva.⁶