© Carl Olof Jonsson, Göteborg, Sweden, 2000


The following material is adapted from the discussion on pages 44-48 of the first and second editions of my book, The Gentile Times Reconsidered (published in 1983 and 1986), with some updates and additions.



PROFESSOR ROBERT R. NEWTON (who died in 1991) was a noted physicist who has published a series of outstanding works on the secular accelerations of the moon and the earth. He examined in detail hundreds of astronomical observations dating all the way from the present back to about 700 BC, in order to determine the rate of the slowly changing of the length of the day during this period. The best information on his research in this area is found in his book, The Moon’s Acceleration and Its Physical Origins, vol. 1, published in 1979. His results have more recently been further refined by other scholars, in particular by F. Richard Stephenson. (Historical Eclipses and Earth’s Rotation, Cambridge: Cambridge University Press, 1997)


Accusations against Claudius Ptolemy not new

The claim that Claudius Ptolemy ”deliberately fabricated” many of his observations is not new. Astronomers have questioned Ptolemy’s observations for centuries. As early as 1008 AD ibn Yunis concluded that they contained serious errors, and by about 1800 astronomers had recognized that almost all of Ptolemy’s observations were in error. In 1817, Delambre asked: ”Did Ptolemy do any observing? Are not the observations that he claims to have made merely computations from his tables, and examples to help in explaining his theories?” – J.B.J. Delambre, Histoire de l’Astronomie Ancienne, Paris 1817, Vol. II, p. XXV; as quoted by Robert R. Newton in The Moon’s Acceleration and Its Physical Origins [MAPO], Vol. I, (Baltimore and London: The Johns Hopkins University Press, 1979), p. 43. 

     Two years later (in 1819) Delambre also concluded that Ptolemy fabricated some of his solar observations and demonstrated how the fabrication was made. (Newton, MAPO I, p. 44) More recently, other astronomers have re-examined Ptolemy’s observations and arrived at similar results. One of them is Professor Robert R. Newton. In his book, The Crime of Claudius Ptolemy (Baltimore and London: The Johns Hopkins University Press, 1977), Newton claims that Ptolemy fudged, not only a large body of the observations he says he had made himself, but also a number of the observations Ptolemy attributes to other astronomers, including some he quotes from Babylonian sources. These include the three oldest observations recorded in Ptolemy’s Almagest dating from the first and second years of the Babylonian king Merodach-baladan (called Mardokempados in Almagest), corresponding to 721 and 720 BC.


Scholars disagreeing with R.R. Newton

     In the ensuing debate a number of scholars have repudiated Newton’s conclusions. They have argued that Newton’s arguments ”are marred by all manner of distortions” (Bernard R. Goldstein of the University of Pittsburgh in Science, February 24, 1978, p. 872), and that his case collapses because ”it is based on faulty statistical analysis and a disregard for the methods of early astronomy” (scholars Noel M. Swerdlow of the University of Chicago, Victor E. Thoren of Indiana University, and Owen J. Gingerich of Harvard University, in Scientific American, March 1979, p. 93, American edition). Similar comments are made by Noel M. Swerdlow, ”Ptolemy on Trial, ” in The American Scholar, Autumn 1979, pp. 523-531, and by Julia Neuffer, ”´Ptolemy’s Canon´ Debunked?” in Andrews University Seminary Studies, Vol. XVII, No. 1, 1979, pp. 39-46. An article by Owen J. Gingerich with a rebuttal by R.R. Newton is found in the Quarterly Journal of the Royal Astronomical Society, Vol. 21, 1980, pp. 253-266, 388-399, with a final response by Gingerich in Vol. 22, 1981, pp. 40-44.


Scholarly support for R.R. Newton

     Most of these critics, though, are historians without particular expertise in the field of Greek astronomy. Some reviews written by well-informed astronomers have been favorable to Newton’s conclusions. One historian who is also well acquainted with Greek astronomy, K.P. Moesgaard, agrees that Ptolemy fabricated his astronomical data, though he feels it was done for some honest reason. (K.P. Moesgaard, ”Ptolemy’s Failings,” Journal for the History of Astronomy, Vol. XI, 1980, pp. 133-135) Rolf Brahde, too, wrote a favorable review of Newton’s book in Astronomisk Tidskrift, 1979, No. 1, pp. 42,43.

     B.L. van der Waerden, Professor of Mathematics and an expert on Greek astronomy, discusses Newton’s claims in his book, Die Astronomie der Griechen (Darmstadt: Wissenschaftliche Buchgesellschaft, 1988). Although he would not go as far as Newton in his attack on Ptolemy, he agrees that Ptolemy falsified his observations, stating: ”That Ptolemy systematically and intentionally has falsified his observations in order to bring his observational results in agreement with his theory have been convincingly demonstrated by Delambre and Newton.” (p. 253)


Recent criticism of R.R. Newton

     G.J. Toomer, the well-known translator of Ptolemy’s Almagest (London: Gerald Duckworth & Co., 1984), discusses Newton’s claim in an article published in 1988 (”Hipparchus and Babylonian Astronomy,” in A Scientific Humanist. Studies in Memory of Abraham Sachs, eds. E. Leichty, M. DeJ. Ellis, & P. Gerardi, Philadelphia, 1988, pp. 353-362), in which he convincingly argues that all the observations from earlier periods recorded by Ptolemy were taken over from the Greek mathematician Hipparchus (2nd century BC).

     In 1990, Dr. Gerd Grasshoff included a lengthy section on the accusations against Claudius Ptolemy in his work, The History of Ptolemy’s Star Catalogue (London, Paris, Tokyo, Hong Kong: Springer-Verlag, 1990, pp. 79-91). He concludes that Newton’s arguments against Ptolemy are ”superficial” and ”unjustified”.

     More recently, Oscar Sheynin has discussed Newton’s accusations at some length, arguing that the reason why Ptolemy’s observations so well agree with his theory is, not that he fabricated them, but that he selected the observations that best fitted his theory. Although such selectivity is not allowed in science today, it was quite common in ancient times. For this reason Sheynin states that Ptolemy cannot be regarded a fraud. – O. Sheynin, ”The Treatment of Observations in Early Astronomy,” in C. Truesdell (ed.), Archive for History of Exact Sciences, Vol. 46:2, 1993, pp. 153-192. 

     In summary, there seems to be at least some evidence in support of the claims that Claudius Ptolemy was ”fraudulent” in the way he handled his observations, either by ”trimming” the values or by selecting those who best fitted his theory. However, few scholars would go as far as R. R. Newton, who dismisses Ptolemy altogether as a fraud. As Dr. James Evans notes, ”very few historians of astronomy have accepted Newton’s conclusions in their entirety.” – Journal for the History of Astronomy, Vol. 24, Parts ½, February/May, 1993, pp. 145-146.


R.R. Newton and ”Ptolemy’s Canon”

In a review of Newton’s book, The Crime of Claudius Ptolemy, published in Scientific American of October 1977, pp. 79-81, it was stated that ”Ptolemy’s forgery may have extended to inventing the length of reigns of Babylonian kings.” This was a reference to the so-called ”Ptolemy’s Canon”, which Newton at that time erroneously believed had been composed by Claudius Ptolemy himself and thus may have been affected by his ”forgery”. The statement was quickly picked up and published in The Watchtower magazine (December 15, 1977, p. 747). On page 375 of his The Crime of Claudius Ptolemy, Newton also wrote: ”It follows that Ptolemy’s king list is useless in the study of chronology, and that it must be ignored. What is worse, much Babylonian chronology is based upon Ptolemy’s king list. All relevant chronology must now be reviewed and all dependence upon Ptolemy’s list must be removed.”

     Newton was unaware of the fact that ”Ptolemy’s Canon” was not composed by Claudius Ptolemy. He was not an historian and he was not an expert on Babylonian chronology. He also admits in his work that he has not studied sources other than Ptolemy for the years prior to Nebuchadnezzar. (The Crime of Claudius Ptolemy, p. 375) He explains that his thoughts on the relations between chronology and the work of Claudius Ptolemy were influenced by a Mr. Philip G. Couture of Santee, California. In the Preface of his book he states: ”I thank Mr. Philip G. Couture of Santee, California for correspondence which led me to understand some of the relations between chronology and the work of Ptolemy.” (The Crime of Claudius Ptolemy, p. XIV) The same Mr. Couture also induced Dr. Newton to reject the Assyrian eponym canon in his work, The Moon’s Acceleration and Its Physical Origins. (See Vol. 1, 1979, p. 189)

     What Newton probably did not know was that Mr. Couture was and still is one of Jehovah’s Witnesses, and that some of the chronological arguments he passed on to Newton were taken from the Watch Tower Society’s Bible dictionary, Aid to Bible Understanding. These arguments were not only aimed at supporting the chronology of the Watch Tower Society, but they are also demonstrably untenable!


Correspondence with R. R. Newton

     In 1978, the year after The Crime of Claudius Ptolemy had been published, I had some correspondence with Professor Newton. In a letter dated June 27, 1978, I sent him a shorter study I had prepared in which the so-called ”Ptolemy’s Canon” was compared with earlier cuneiform sources. This study briefly demostrated that all the reigns of the Babylonian kings given in the Canon, from Nabonassar (747-734 BC) to Nabonidus (555-539 BC), were in complete agreement with these older sources. (This study was later expanded and published in a British journal for interdisciplinarty studies, the British forum for the discussion of the catastrophe theories of Immanuel Velikovsky and others: Chronology & Catastrophism Review, Vol. IX, 1987, pp. 14-23.) I asked Professor Newton: ”How is it possible that Ptolemy’s astronomical data are wrong, and yet the king list, to which they are attached, is correct?”

     In his answer, dated August 11, 1978, Newton said: ”I am not ready to be convinced that Ptolemy’s king list is accurate before Nabopolassar [= before 625 BC], although I have high confidence that it is rather accurate for Nabopolassar and later kings.” He also pointed out: ”The basic point is that Ptolemy calculated the circumstances of the eclipses in the Syntaxis from his theories, and he then pretended that his calculated values were values that had been observed in Babylon. His theories are accurate enough to give the correct day of an eclipse, but he missed the hour and the magnitude.”

     Thus Ptolemy’s ”adjustments” of the eclipse observations were too small to affect the year, the month, and the day of an eclipse. Only the hour and the magnitude were affected. Ptolemy’s supposed ”adjustments” of the records of the ancient Babylonian eclipses, then, didn’t change the BCE dates that had been established for these observations. They did not change the chronology! Further, Professor Newton was convinced that the king list was accurate from Nabopolassar and onwards. In other words, he was convinced that the whole Neo-Babylonian chronology from Nabopolassar through Nabonidus (625-539 BC) was accurate! Why?

     The reason was that Newton had made a very thorough study of some of the ancient Babylonian astronomical records that were independent of ”Ptolemy’s Canon”, including the two astronomical cuneiform texts designated VAT 4956 and Strm. Kambys. 400. From his examination of these two records, he had established that the first text referred to the year 568/67 BC and the second one to 523 BC. He concluded: ”Thus we have quite strong confirmation that Ptolemy’s list is correct for Nebuchadrezzar, and reasonable confirmation for Kambyses.” (The Crime of Claudius Ptolemy, 1977, p. 375) These findings were further emphasized in his next work, The Moon’s Acceleration and Its Physical Origins, vol. 1, published in 1979, where he concludes on page 49: ”Nebuchadrezzar’s first year therefore began in –603 [= 604 BC], and this agrees with Ptolemy’s list.”

     Therefore, to quote some statements by R. R. Newton in an attempt to undermine the chronology established for the Neo-Babylonian era would be to quote him out of context. It would be to misrepresent his views and conceal his conclusions. It would be fraudulent. Yet, this has been repeatedly done by the Watch Tower Society and some defenders of its chronology. But Newton’s findings refute their chronology and prove it to be false.



Whether Ptolemy falsified his observations, perhaps also some of those of earlier astronomers, is irrelevant for the study of the Neo-Babylonian chronology. Today, this chronology is not based upon the observations recorded by Ptolemy in his Almagest.

    Further, the claim that Ptolemy may have ”invented” the lengths of reign in ”Ptolemy’s Canon” is based upon the erroneous view that this king list was composed by Claudius Ptolemy. As is demonstrated on pages 94-96 of the third edition of The Gentile Times Reconsidered (and also briefly in the second edition), the designation ”Ptolemy’s Canon” is ”a misnomer” (Otto Neugebauer), as this king list according to Eduard Meyer, Franz X. Kugler and others had been in use among Alexandrian astronomers for centuries before the time of Claudius Ptolemy, and had been inherited and brought up-to-date from one generation of scholars to next.

    Finally, the claim that this king list today is the basis of or principal source for the Neo-Babylonian chronology, is false. Those who make such a claim are either ignorant or dishonest. The plain truth is that the king list is not needed today for fixing the chronology of this era, although its figures for the reigns of the Neo-Babylonian kings are upheld by at least 14 lines of independent evidence based on cuneiform documents, as is demonstrated in The Gentile Times Reconsided.


Addition in 2003:

Modern scholars who have examined the so-called Ptolemy’s Canon (more correctly called the ”Royal Canon”) in detail agree that the kinglist has proved to be reliable from beginning to end. This is emphasized, for example, by Dr Leo Depuydt in his article, ”More Valuable than all Gold: Ptolemy’s Royal Canon and Babylonian Chronology,” published in Journal of Cuneiform Studies, Vol. 47, 1995, pp. 97 -117. Quite recently, Leo Depuydt has written another article in which he discusses the reliability of Ptolemy’s Canon, "The Shifting Foundation of Ancient Chronology," soon to be published in Acts of European Association of Archaeologists, Meeting VIII.


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