VCA: Appendix 2: The Role of Greek Influence in Indian Astronomy
Appendix 2
The Role of Greek Influence in Indian Astronomy
As we pointed out in Section l.b, Western scholars maintain that the mathematical astronomy of the siddhantas was borrowed from Greek and Babylonian astronomy in the early centuries of the Christian era. In this appendix we will make a few observations suggesting that this hypothesis is not at all proven. We will not attempt an exhaustive treatment of the many arguments advanced by scholars, since this would require a large book. Rather, we will make a few points intended to show the quality of the scholars' arguments and the nature of the historical evidence used by scholars to present their case.
To begin, we should note that the history of ancient Western astronomy revolves around Claudius Ptolemy, an Alexandrian astronomer who lived in the second century A.D. Ptolemy is famous for writing a book on astronomy-the Syntaxis, or Almagest-that dominated Western astronomical thinking for over a thousand years. It turns out that, apart from Ptolemy's Almagest, we have very little historical evidence regarding ancient Greek astronomy. Neugebauer describes the situation as follows in his three-volume work on ancient astronomy. Concerning his discussion of Greek astronomy before Ptolemy, he says,
With book IV [on pre-Prolemaic Greek astronomy] we entered an entirely new situation, where a later period had effaced all but vague and confused reports of its prehistory. This condition prevails right down to Ptolemy; without his historical remarks we would know almost nothing about the astronomy of Hipparchus or Apollonius (NG, p. 781).
Concerning the Roman-Byzantine period following Ptolemy, Neugebauer says,
Over and over again attempts to see more clearly into the transmission of scientific knowledge within the Roman-Byzantine world and beyond its boundaries are made impossible by the absence of published texts.... It is obvious that at present any attempt at writing a historical narrative would be utterly unsatisfactory. The chances are slim that the future will be much better" (NG, p. 781).
As a result, we can divide the history of ancient Western astronomy into three periods: (1) pre-Ptolemaic, (2) the time of Ptolemy himself, and (3) post-Ptolemaic. Of these, we have substantial knowledge only of (2), as revealed by the Almagest. Due to our lack of solid evidence regarding period (1), we do not know the origins of Greek and Babylonian astronomy, and thus we cannot rule out the possibility that many astronomical ideas attributed to the Greeks may have come originally from India. And because of our ignorance of period (3), we have no solid basis for saying that these ideas were transmitted to India from Greek sources during the time of the decline and fall of the Roman Empire.
Nonetheless, even though our knowledge of the history of ancient astronomy is extremely incomplete, there are scholars who believe that they can uncover important parts of this history by speculative reconstruction. One example of this is a paper entitled "The Recovery of Early Greek Astronomy from India," by David Pingree (PG). In order to indicate the complexities and pitfalls of the speculative process, we will examine the key argument of this paper in detail. This will involve the use of a number of technical astronomical terms, but we will explain these as we go along. Our method will be to first present Pingree's theory, and then give his reasons for accepting this theory as true. Then step by step we will show the fallacies in his reasoning and present an alternative theory that is in better agreement with the facts.