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The Siddhāntasundara of Jñānarāja: An English Translation with Commentary

Toke Lindegaard Knudsen
Johns Hopkins University Press
Publication Date: 
Number of Pages: 
[Reviewed by
Glen Van Brummelen
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One important motive to study the history of science is to come to terms with the diversity of possible cultural reactions to the same phenomenon. We can learn a great deal about others, and more importantly about ourselves, by witnessing the extent to which someone raised in a foreign culture can look into the heavens (for instance), and see something quite different than what we see. One of the best places to experience this cultural and intellectual dissonance is in the astronomical texts of medieval India. However, such texts have been difficult to access in the West.

The book under review takes one step toward making Indian astronomy more accessible. The Siddhāntasundara by Jñānarāja, a very late (early 16th century) astronomical treatise squarely in the Indian astronomical tradition, was described by the late David Pingree as “the last important siddhānta not to have been published.” The siddhānta was the most important genre in the Indian tradition, a comprehensive work containing mathematical algorithms needed to locate celestial bodies and make predictions, but also the theory underlying the work. This volume presents an English translation and commentary of the sections on cosmology and mathematical astronomy. Although the author argues that another treatise by Jñānarāja on mathematics should be considered to be part of the Siddhāntasundara, he does not include it here. The original Sanskrit is not included in this book (a non-critical edition of the text appeared in 2008), but the author promises a critical edition in due time.

With respect to the astronomical content, this work does not vary dramatically from the other siddhāntas. All Indian astronomy is geocentric, likely originating from a transmission of some Greek theory dated before Claudius Ptolemy; Jñānarāja’s work is no exception. For the motions of each planet, two epicycles are employed (the manda, “slow”; and the śīghra, “fast”). They are dealt with separately, which emphasizes that the role of the geometric theory was intended more to produce predictions of positions than to posit to the planet’s motion some underlying geometric truth. The remainder of the astronomical section deals with various planetary phenomena, especially eclipses. The section on cosmology comes first in the book, unusual for a siddhānta.

Several interesting characteristics are noteworthy in this text. One is its poetic use of language. For instance, in order to translate a given passage successfully, to represent the intertwined meanings two entirely different English translations are sometimes required: one narrative, the other technical. One also finds at the end of the cosmological treatise a poetic account of the six traditional Indian seasons, a rare (although not unprecedented) inclusion in a technical astronomical work. Knudsen’s consideration of the Siddhāntasundara’s sources and purpose is also interesting. Jñānarāja mentions most of the great Indian astronomers in his book; one of his main goals, however, seems to have been to promote his main source, the otherwise obscure Brahmasiddhānta. Somewhat surprisingly given the late date, we find little to no evidence of the influence of Islamic science.

Knudsen’s book is nicely laid out, with translations of passages in bold print rarely extending beyond half a page, each followed with extensive and clear explanations. This allows the reader to navigate easily between the translation and commentary. This volume is an important contribution to the research literature, but I hope it will also find a broader audience among mathematically competent readers who wish to taste a familiar topic cast in an unfamiliar way.

Glen van Brummelen is a founding faculty member at Quest University Canada. He is the author of Heavenly Mathematics: The Forgotten Art of Spherical Trigonometry and The Mathematics of the Heavens and the Earth: The Early History of Trigonometry.

The table of contents is not available.