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The Myth of Babylonian Knowledge of Precession by Gary D. Thompson

Copyright � 2004-2008 by Gary D. Thompson


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The Myth of Babylonian Knowledge of Precession

A central claim of the Panbabylonists (a group of German Cuneiform Philologists and Assyriologists at the beginning of the 20th-century) was that the Babylonians had discovered precession. The various forms of proof included arguments involving: believed early Babylonian ability for accurate observations and involved calculations, calendrical systems, believed early zodiacal scheme, solstice-equinox-Sirius texts, the Astronomical Diaries, zero points in System A and System B, and legends and symbols. The hypothesis that the Babylonians knew precession can be confidently dismissed. The hypothesis has been adequately refuted by the studies of the astronomer and Assyriologist Franz Kugler, the mathematician Otto Neugebauer, and the Assyriologist Abraham Sachs.

Franz Kugler was a pioneer of the study of mathematical-astronomical cuneiform texts and also calendrical texts. His refutation of the Panbabylonist arguments for Babylonian knowledge of precession is contained in his Sternkunde und Sterndienst in Babel (1907-1924). The ideas that a 12-constellation equally divided Babylonian zodiac originated circa 6000 BCE (promoted by the Panbabylonists Fritz Hommel and Alfred Jeremias) did not begin to be entirely discarded until the monumental multi-volume Sternkunde und Sterndienst in Babel by Franz Kugler began publication in 1907. Franz Kugler, in his numerous clashes with the Panbabylonists Fritz Hommel, Alfred Jeremias, and Ernst Weidner, convincingly demonstrated that the Babylonians had a late and sidereal zodiac and a late mathematical astronomy. This meant that precession could not have been marked at an early date through either the constellations or signs of the zodiac. Also, from his study of cuneiform texts Kugler pointed out that the concept of precessional movement of the tropical points through ecliptic constellations was not contained in early Babylonian astronomical texts. There is nothing in the Babylonian texts to prove a Twins-, Bull-, and Ram-period of precession. The ecliptic only became important in the 1st millennium BCE. There was certainly no pre-first millennium zodiac for observing and measuring precessional “zodiacal ages.” A zodiac for being able to do such only came into existence in the last half of the 1st millennium BCE.

In addition to the above Otto Negebauer pointed out (“Babylonian Planetary Theory.”, Proceedings of the American Philosophical Society, Volume 98, 1954, Page 64): “There is no trace of any definition of the vernal point as the intersection of ecliptic and equator (which appears nowhere in Babylonian astronomy).”.

The Ram was an important cult figure in both ancient Egyptian and Babylonian civilizations – but not a constellation. The Ram is a Greek constellation. When the Greeks borrowed the zodiacal system from Babylonian uranography the Babylonian constellation of the “Hired Man” was replaced by the Ram. (For a philological explanation of how this may have occurred see “Zodiacal Signs among the Seal Impressions from Hellenistic Uruk.” by Ronald Wallenfels in: The Tablet and the Scroll, edited by Mark Cohen et. al., 1993, Pages 282-283.)

Unfortunately the myth of a prehistoric 12-constellation zodiac (of equal divisions) is not yet dead. The importance of the ecliptic and the development of the 12-constellation zodiac does not appear anywhere until its origin in Babylonia circa 700 BCE.. The development of the equally divided 12-constellation zodiac does not appear until after the start of the Persian Period in Babylonia (circa 500 BCE). The cuneiform tablet evidence clearly establishes that it was the astronomy of the Mul.Apin scheme (circa 1000 BCE) that established the preconditions for the importance of the ecliptic and the establishment of the Babylonian zodiacal scheme which was later adopted by the Greeks. The Babylonian scheme of 12 zodiacal constellations was derived from a system of 18 constellations (established during the Assyrian Period beginning circa 1100 BCE) along the ecliptic to mark the path of the Moon. (Prior to circa 1000 BCE the ecliptic was not specifically marked in Babylonian astronomy. The three path system of the “three stars each” was established and in effect was an equatorial system. However, the Babylonians clearly had no concept of a celestial equator.) Circa 700 BCE (toward the Neo-Babylonian Period) the scheme of 18 constellations used to mark the path of the moon were then reduced to a scheme of 12 (unequal) constellations along the ecliptic to suit a schematic year of 12 months of 30 days each. This scheme was finally achieved with the division of the zodiac into 12 equal divisions (during the Neo-Babylonian period). (The constellations not wholly occupying the ecliptic were removed.) The scheme of 12 constellations (and 12 zodiacal divisions of equal length) was the last scheme of constellations (and divisions) to be finalised (and is not older than the 5th-century BCE). However, the individual constellations included in the zodiacal scheme have far earlier origins and some can be dated back 1500 years to the Old Babylonian Period. The evidence is conclusive that a system of 12 equal zodiacal divisions did not exist until circa 450 BCE. This date is the earliest from which there was a possible basis for the determination of precessional “zodiacal ages.” However, precession remained undiscovered until the work of the Greek astronomer Hipparchus circa 120 BCE.

Hipparchus had the benefit of the concept of the ecliptic and 12 zodiacal constellations, a solid concept of the equinoxes and solstices, plus a geometrical model of the earth in space, to work with. Importantly, he also had the positions (i.e., declinations) of some 25 stars near the ecliptic (established the previous century by the Greek astronomers Timocharis and Aristyllos). There is no evidence to establish that anybody earlier than the Greeks circa 500 BCE had the same collection of concepts. If the Babylonians (or some other cultural group) were aware of precession prior to 1000 BCE then they did not have the combined benefit of the concept of the ecliptic, an equally-divided 12-constellation zodiac, a geometrical perspective of the heavenly bodies, and the abstract moving points of the equinoxes and solstices. Thus if an early group became aware of precession they can not be expected to have explained it in the same way Hipparchus did.

When the zodiacal system was first being devised (over the period circa 700 BCE to 500 BCE) it is evident that precession had not been discovered. The Babylonian astronomers who first originated the zodiac did not attempt to measure the zodiac from an invisible tropical point they were unable to observe (and could only approximate). It was easiest for them to observe the fixed stars and the zodiac was tied to the fixed stars. The Babylonian astronomers simply defined the starting points of the zodiacal signs by their positions relative to the fixed stars. The Babylonians simply placed the tropical points in the middle of the relevant signs (i.e., 15 degrees Aries per Mul.Apin) or related them to fixed stars (i.e., put the vernal point at 10 degrees Aries per System A, or 8 degrees Aries per System B). (It appears it was the Greek astronomer Hipparchus who was the first to identify the “first point of Aries” with the vernal point.) It would appear that the Babylonians had no suitable understanding of the tropical points, at least for most of their history. Up til the 7th-century BCE most administrative and astronomical texts show an almost exclusive use of a schematic calendar comprised of twelve 30-day months. Its use is evidenced in administrative texts from Uruk III at the end of the 4th millennium BCE and from Jemdet Nasr throughout the 3rd millennium BCE. In astronomical texts its use is evidenced in BM 17175 (from the Old Babylonian Period); the series Mul.Apin (from the Assyrian Period); Tablet 14 of the omen series Enuma Anu Enlil (circa the Cassite Period); the series I.NAM.GIS.HUR.AN.KI.A (from the Middle Babylonian Period); and also in the various “Three Stars Each” star calendar texts (which date from the Middle Babylonian Period. In all these astronomical texts the solstices and the equinoxes are equidistantly spaced at the midpoints (i,e, day 15) of certain months – usually months 3 (summer solstice), 6 (autumn equinox), 9 (winter solstice), and 12 (spring equinox). (In the series Mul.Apin (and also in BE 13918 and the “Ivory Prism,” both from the Neo-Assyrian Period) there is a change in calendar practices and the dates of the solstices and equinoxes are shifted by one month.) The basic method of the Babylonians for determining the tropical points was simply to observe the summer solstice and then the position of the other solstice and the equinoxes were found by adding approximately 3, 6, or 9 months. (For a discussion of the methods used to determine the solstices and equinoxes see: Astral Sciences in Mesopotamia by Hermann Hunger and David Pingree (1999; Pages 75-77).)

Kugler also pointed out that the lack of accurate calculation and observation in early records of eclipses and of the planets demonstrates the absence of a precise system of measuring location and time in the sky. Precise date and position details are not given for any early observations. The total eclipse observed in 763 BCE was only recorded by the simple statement: “In the month Sivan an eclipse of the Sun took place.”

Until the (Late) Assyrian Period Mesopotamian astronomy is simply qualitative. Astronomical observations the early period of Mesopotamian astronomy show little exactness. The Venus observations made during the reign of Ammizaduqa were made in order to provide empirical material for omina. It is only from the (Late) Assyrian Period that the mathematical treatment of astronomy begins. Also, it is only from this period that systematic observational reports begin to appear.

Importantly, the development of latitude and longitude as astronomical coordinates did not occur before circa 200 BCE. (It was only during the Seleucid Period (beginning circa 200 BCE) that techniques were developed for determining the positions of celestial bodies in terms of degrees of latitude and longitude.) The inaccurate nature of the calendar for approximately 2000 years is inconsistent with an ability for careful and systematic observations. Before the 7th-century BCE almost all astronomical texts used the schematic calendar of twelve 30-day months. The absence of an accurate calendar also makes it difficult to easily discover precessional change. (See: Sternkunde und Sterndienst in Babels, Buch 2, Teil 1,1909/10, Pages 20-31; and Buch 2, Teil 2, Heft 2, 1924.) The lack of an accurate calendrical system and the lack of exactitude in early Babylonian astronomy makes it implausible to believe that a continuous series of precise observations, and accompanying accumulation of continually maintained records, was possible. Changes in the position of the sun relative to the tropical points is a fraction of a degree per year and difficult to observe simply because when the sun is visible the fixed stars are not.

In his 1914 paper “Die Entdeckung der Pr�zession, eine Geistestat babylonischer Astronomen.” (Babyloniaca, Tome 7, Pages 1-19) Ernst Weidner attempted to prove that the Babylonians knew of precession at least by circa 1500 BCE. His argument was that the dates of the solstices and equinoxes in a tablet (CBS 11901) which he dated to circa 1500 BCE were approximately correct as were the dates of the solstices and equinoxes in tablets dating from circa the 6th-century BCE. However, Kugler (Sternkunde und Sterndienst in Babels, Erganzungen 2 f�r Buch 1 und Buch 2, Pages 233-242) demonstrated that the cuneiform tablet (CBS 11901 (= LBAT 1478)) that Weidner dated to circa 1500 BCE was actually to be correctly dated to 424/3 BCE.

Standardisation of the calendar was necessary for the discovery of precession. The lunar calendar scheme was unsuitable for anything but approximate time timekeeping. The early introduction of the use of the ideal or schematic year of 360 days still posed problems for accurate time measurement. (The observation-based Babylonian month had 29 or 30 days. If the crescent moon was already visible at the beginning of day 30 in a month, this day 30 was rejected, which meant that the month only had 29 days.) Early Babylonian calendars were rather awful regarding accuracy and were simply adjusted (intercalated) on an arbitrary basis. They remained chaotic through to the late first millennium BCE. For most of their history the Babylonians had no method of keeping the lunar year and the solar year together. This precludes the keeping of accurate astronomical records. The Assyrian calendar of the second millennium BCE did not use intercalation at all and drifted all through the solar year. (The early Babylonians were more interested in having a calendar comprised of uniform numbers than dealing with the non-uniform numbers resulting from exactness.) In Babylonia the year began at about the time of the spring equinox.

In the Astrolabes of the late 2nd millennium BCE the first day of the first month of the year, the first of Nisan (= March/April), was marked by the approximate conjunction of the first visible crescent Moon with the star group Mul.Iku (= The Field). The observation of the heliacal rising of Mul.Iku on the eastern horizon (just before sunrise) and then the first appearance of the crescent new Moon at dusk on the western horizon marked the beginning of the new year. In the Mul.Apin series of the 1st millennium BCE Mul.Mul (= Pleiades) was the star group that functioned to mark the new year (the first of Nisan). In the spring when the Pleiades rose heliacally on the eastern horizon (just before sunrise) in conjunction with the first visible crescent Moon on the western horizon (at dusk) it marked the first day of the month Nisan (and the beginning of the new year). However, as the sequence of years of 12 and 13 months was very irregular sometimes the year began earlier and sometimes it began later. (The identification of the Babylonian calendar months were aided by the use of the scheme of the “three stars each” which enabled the Babylonians to know when the lunar months were shifting out of correlation with the seasons. The “three stars each” consisted of a month-by-month listing of constellations, stars, and planets which rose heliacally (on the eastern horizon) in each of the twelve 30-day months of the schematic year. For each month a star was assigned to each of the “three ways” (i.e., the paths of Anu, Enlil, and Ea) and rose at 10 day intervals. At first they were recorded as a circular pictorial representation and then later as a listing only.) No cyclically regulated intercalation (to control the calendar) existed in Babylonian prior to the Persian Period (circa 450 BCE). When finally introduced the unit of intercalation was simply the lunation (and was used as needed to keep the calendar year in line with the seasons). When the grain was ready for harvest was the key issue in determining intercalation. The time of a star’s heliacal rising changes at the rate of about a month approximately every two thousand years. The way the Babylonian calendar operated there is no reason to suppose that the calendar error would become really conspicuous until after approximately 2000 years. This brings us down to the Late Hellenistic Period. Also, there is no identified tradition of long-term seasonal displacement of familiar stars used as markers.

Otto Neugebauer spent a life-time engaged in the study of mathematical-astronomical cuneiform texts. His decisive demolition of Paul Schnabel’s argument for Babylonian knowledge of precession (“Kidenas, Hipparch und die Entdeckung der Pr�zession.” (Zeitschrift f�r Assyriologie und Verwandte Gebiete, Neue Folge, Band 3 (Band 37), 1927, Pages 1-60)) is contained in his paper “The Alleged Babylonian Discovery of the Precession of the Equinoxes.” (Journal of the American Oriental Society, Volume 70, Number 1, 1950, Pages 1-8). In this paper and his earlier book Berossos und die babylonisch-hellenistische Lieratur (1923, Pages 233-237) Schnabel.had claimed that the Babylonian astronomer Kidinnu had discovered precession at (mistakenly, due to an earlier translation error made by Franz Kugler) Sippar. The date offered in 1923 was 313 BCE but this was changed in his 1927 paper (in which he offered further arguments to counter the criticisms made by Franz Kugler in Sternkunde und Sterndienst in Babel (Buch 2, Teil 2, Heft 2, 1924) Pages 582-621 and Pages 627-630) to 378 BCE. Paul Schnabel basically proposed that the 4th-century BCE astrologer/mathematician Kidinnu discovered precession when distinguishing between sidereal and tropical years. Schnabel’s argument for the Babylonian discovery of precession was based on a commonly made scribal numerical error (the interchange of cuneiform 4 and 7). The other half of the text used by Schnabel was later located in Chicago and it contained other scribal errors that more than outbalanced the one that Schnabel had taken seriously. Also included in Schnabel’s main argument for the Babylonian discovery of precession was was that System B developed from System A. This was undermined by (1) evidence for the near contemporary development of both systems, and (2) their different provinces in Babylon (for System A) and Uruk (for System B). Also, System A and System B were used contemporaneously. Tablets for both systems have been found in both Babylon and Uruk. Tablets based on System B have been found mostly in Uruk, but the somewhat earlier System A tablets came predominantly from Babylon.

In his monumental A History of Ancient Mathematical Astronomy (3 Parts, 1975) Neugebauer wrote (Part 1, Page 369): “We have no evidence from Babylonian sources about a recognition of precession and we have no reason to assume that the difference of zero points in System A and B had anything to do with it, knowingly or unknowingly. … That the vernal point maintained in each of the two systems a fixed sidereal longitude indicates that precession was unknown.”

Also relevant are the solstice-equinox-Sirius texts. (These texts formed part of the Astronomical Diaries. Hermann Hunger and David Pingree write (Astral Sciences in Mesopotamia (1999) Page 151): “The only aspects of solar motion mentioned in the diaries are the dates of the occurrences of solstices and equinoxes and of the heliacal rising and setting and the acronychal rising of Sirius.”) The phases of Sirius and other fixed stars were put into a definite relation to the solstice-equinox scheme. (The term “phases” of a star relates to horizon aspects of apparent movement. The four important “phases” of a star were heliacal rising (its first visible rising above the eastern horizon just before sunrise) and heliacal setting (its last visible setting below the western horizon just after sunset); and acronychal rising (when it first rises above the eastern horizon just as the sun sets below the western horizon) and acronychal setting (when it first sets below the western horizon just as the sun rises above the eastern horizon). Both the heliacal and acronychal risings and settings are directly observable phenomena.) These texts contain information setting out the positions of Sirius and other stars relative to the solstice and equinox points. The discussion by Neugebauer (A History of Ancient Mathematical Astronomy, Part 1, Page 543) of these solstice-equinox-Sirius texts, which date from circa the 6th-century BCE through to the Seleucid Period, shows that the position of Sirius relative to the solstices and equinoxes does not change over time with precession as would be expected had the Babylonians known of such. The earliest Sirius dates circa 600 BCE are the same as those of the later period. (The scheme found in BM 36731 lists equinoxes, solstices, and heliacal risings and settings of Sirius from, it would appear, 615-587 BCE. The solstice-equinox-Sirius dates are resumed again by the Astronomical Diaries in 330 BCE.) Neugebauer (A History of Ancient Mathematical Astronomy, Part 1, Page 543, Note 13) concludes: “This is, incidentally, further evidence for the fact that the Babylonian astronomers were not aware of the existence of precession.”

See also the early study by Abraham Sachs on the dates of the phases of Sirius related to the solstice and equinox schemes: “Sirius Dates in Babylonian Astronomical Texts of the Seleucid Period.” by Abraham Sachs (Journal of Cuneiform Studies, Volume 6, 1952, Pages 105-114). Simply, the dates of all solstices and equinoxes found in Seleucid texts are the result of computation according to a fixed scheme. Observation was not involved. A succinct summary explanation is given by Hermann Hunger in his booklet Astrology and Other Predictions in Mesopotamia (1997, Page 29): “The dates of the equinoxes and solstices and the appearance of the star Sirius are all given according to a schematical computation; so these are not observations.” For the Babylonians the arrangement of the solstices and equinoxes are part of the schematic year – they are simply established within the time frames of the ideal 360-day year. The Babylonians show no awareness of actual periodicities and only modest observational foundations are indicated as forming the basis for their calculated schemes.

Within the methods and results of Babylonian astronomy very great emphasis was placed on schematization. The main concern of Babylonian astronomy was convenience of numerical manipulation and the intent to solve complicated periodic relationships by the use of successive approximations based on arithmetical progressions. As such the dates of solstices and equinoxes were the result of computation according to a fixed scheme. There is no evidence at all that during the entire Assyrian Period the spring equinox had any significance for the beginning of the year. The equinoxes and solstices had no effect on the Mesopotamian calendar.

The idea that the Babylonian knew precession is also refuted by the study of two tablets from Uruk for the computation of summer solstices. (See: “Schematische Berechnungen der Sonnenwenden.” by Hermann Hunger (Baghdader Mitteilungen, Volume 22, 1991, Pages 513-519).)

Abraham Sachs spent the latter part of his career in a detailed study of the Astronomical Diaries. (His work has been continued by the Assyriologist Hermann Hunger.) His detailed studies of these and related texts has established that this uninterrupted 800 year long observational program did not lead to Babylonian knowledge of precession. (See further: Annals of Science, Volume 58, Number 3, July 1, 2001, Pages 323-326.) The data in the Astronomical Diaries and the Almanacs is frequently contradictory. In Babylonian texts the dates of various celestial phenomena may be either observed or computed. The use of calculations based on a combination of theory and observations was frequent. Much of the data recorded in both Astronomical Diaries and Almanacs are not observation-based but computation-based. The comparison of the data in the Astronomical Diaries and Almanacs demonstrates the absence of one unifying and exact observation and computation scheme. Interestingly, all of the data recorded in Normal Star Almanacs are predictions. It is obvious that discovering precession is not as easy as having a grandfather who has a tree and passes down stories about his lifetime observation of the night sky.

In his 1993 book The Eye of Heaven : Ptolemy, Copernicus, Kepler the American historian of science Owen Gingerich offered a succinct explanation for the appearance of preciseness in Babylonian computation schemes (Page 21): “But how could the Babylonians find the length of the seasons so well, since it would have been no easier for them than for Ptolemy to find the time of the solstice by direct observation? The answer seems to lie in the idea that the Babylonian astronomy was thoroughly dependent upon lunar observations, and particularly on a long series of lunar eclipses. Over the past century the astronomical cuneiform tablets have gradually been deciphered, and one of the most surprising things that has emerged is the relatively high accuracy with which parameters can be extracted from very approximate observations. Provided there are enough records over a considerable period of time, even crude measurements furnish quite reliable figures for planetary periods and for their non-uniform motion along the ecliptic. In particular, the Babylonians discovered that the lunar eclipses repeated in certain patterns, and that the possible eclipses positions were more crowded together in the direction of Sagittarius than in Gemini. This meant that the Sun was moving more slowly when it was in Gemini, and more rapidly in Sagittarius. From this observation it was possible to work backward and establish when the seasons began without actually making daytime measurements of the solstices.”

In his paper “The Young Avestan and Babylonian Calendars and the Antecedents of Precession.” (Journal for the History of Astronomy, Volume 10, 1979, Pages 1-22) Willy Hartner suggests that the tropical and sidereal year were distinguished in Babylonian astronomy by 503 BCE and that it implies knowledge of precession. However, there is no evidence that the Babylonians differentiated between the tropical and sidereal year at all. Though the Babylonians, quite late, came to realize that there was a difference between the tropical and and the sidereal mean longitude of the sun there is no evidence that they could rationalise the discrepancy and understand it as the Greek astronomer Hipparchus later did. In his review of Bartel van der Waerden’s 1988 book Die Astronomie der Griechen Alexander Jones writes (Isis, Volume 81, 1990, Page 332): “… van der Waerden revives the old bogey of a Babylonian discovery of precession, because of the discrepancy between the “sidereal” year underlying the system A and B lunar theories and the “tropical” year derivable from the Uruk solstice scheme. But this tropical year is merely a consequence of the nineteen-year calendric cycle, which is both older and of a lower order of accuracy than the lunar theories; the tropical year implicit in system A is identical with the sidereal year, while in system B there is only a small discrepancy that results from the arithmetrical constraints of the zigzag functions.”

It is difficult to understand what is meant when it is claimed by the “new” Panbabylonists such as Giorgio de Santillana and Hertha von Dechend that early cultures must have recognised or understood precession. In seeking to establish who was the first to be aware of precession the zodiac, the tropical points, and the mechanism of precession are not wholly relevant. The questions to ask are: (1) Who in antiquity appears to have been aware of precession?; (2) Can a date for the awareness be assigned?; (3) How did they come to notice it?; (4) What did they notice?; and (5) Was an explanation attempted? However, some sort of vague realisation without quantification or ability to describe it in terms of a precise astronomical coordinate system is not exactly a firmly established discovery. The expected easiest observations of precession (by some early culture at a continuously settled site) would perhaps be (1) the horizon and changes in the heliacal risings of stars, (2) the pole-star and the replacement of one by another over time, and (3) calendrical systems and the adjustments to such. None of the efforts using these arguments have been found to convincingly demonstrate the awareness of precession prior to Hipparchus. However, to perhaps vaguely realize something about the effects of precessional shift is one thing, and it is another thing entirely to suppose that they could have discovered the precession of the equinoxes as did the later Greek astronomer Hipparchus. In his article “The Celestial David and Goliath.” published in 1995 (Journal of the Royal Astronomical Society of Canada, Volume 89, Number 4, Pages 141-154) F[?]. Millar argued that the ancient fear that “the sky is falling” was a description that identified knowledge of precession. The article assumes that an early culture, using the horizon as a measuring instrument, could identify both the slow tilting effect of the sky and also the slow displacement of the pole star and interpret the effects of both as a slow lowering of the sky. (For a further example of pole star myths and collapsing skies see the myth of Boahje-naste discussed in Finno-Ugric and Siberian Mythology by Uno Holmsberg (1927).) However, in interpreting ancient myths we can easily succumb to reading into them whatever we would like to believe. Moreover, the interpretation of myths most usually remains unverifiable.

For a short critique by Otto Neugebauer of the inaccuracies of Giorgio de Santillana as an historian of early science see “The Survival of Babylonian Methods in the Exact Sciences of Antiquity and Middle Ages.” in Proceedings of the American Philosophical Society, Volume 107, Number 6, December 20, 1963, Page 531. See also the short critique of Giorgio de Santillana by Asger Aaboe in the book review “Historians of Science.” in The Yale Review, Volume 52, Winter, 1962, Pages 326-328.

The authors of Hamlet’s Mill hold that the clearest statement of precession exists in the Erra-Epic (also known as the Erra and Ishum Epic). (See: Hamlet’s Mill by Giorgio de Santillana and Hertha von Dechend (1969) Pages 325.) The authors write: “… it is necessary to leave Era’s somber prophecy unfulfilled, relating as it does to a coming world age: “Open the way, I will take the road, The days are ended, the fixed time is past.” But with it comes the clearest statement ever uttered by men or gods concerning the Precession. Says Marduk: When I stood up from my seat and let the flood break in, then the judgement of Earth and Heaven went out of joint … The gods, which trembled, the stars of heaven – their position changed, and I did not bring them back.” The authors fail to to engage in any developed discussion, scholarly or otherwise, of this section of the text. The source of the “Marduk quote” in Hamlet’s Mill is the late version of the Erra-Epic, generally believed by scholars to have been written circa the eighth-century BCE, and is likely derived from (the German-language) book Das Era-Epos by Felix G�ssmann (1956). (The author of the Erra-Epic, Kabti-ilani-Marduk of the Dabibi-family, claimed that the work was revealed to him in a dream. The Erra-Epic is written as a dialogue between gods.) Which author of Hamlet’s Mill made the English-language translation is not known. Unfortunately G�ssmann’s edition of the Erra-epic has problems. In his review of the book (Archive f�r Orientforschung, Achtzehnter Band, 1957-1958, Pages 395-401) the Assyriologist Wilfred Lambert concluded it was not generally reliable. In the Erra-Epic there is a scenario involving disorder affecting the earth and heavens when Marduk temporarily leaves his throne. The context is an apocalyptic type scenario similar to the Biblical book Apocalypse of John (i.e., Book of Revelation). (See the discussion in Cosmos, Chaos and the World to Come by Norman Cohn (1993). Erra is an Akkadian warrior god. The result of Erra’s assault is that the world is plunged into darkness and as a result Marduk is displaced from his throne and forced to descend to the underworld. Erra temporarily seizes control of Babylon from Marduk during the latter’s temporary absence. As the phenomena of precession is completely unconnected with any occurrence of celestial darkness this type of imagery can hardly be descriptive of precession. The actual point being made by the story is the equilibrium of the physical and moral world (both equally divine appointments) depend on the presence of the god Marduk.

The theme of the chosen imagery of the Erra-Epic is believed to refer to a disastrous military event that occurred to the city of Babylon in the “dark age” at the beginning of the first millennium BCE. The central theme of the poem is concerned with the assault by Erra on the kingdom of Marduk. Babylon was the residence of the god Marduk and the centre of the universe. The disaster was interpreted in religious terms as the temporary replacement of Marduk by Erra. It is likely the poem is descriptive of a raid by the semi-nomadic Sutian people on the city of Babylon. It is most likely the Sut� raids of the 11th-century BCE were the background of the Epic. The Sut� tribes created havoc in Babylonia shortly after 1100 BCE. The Sut� (Aramaean tribes who lived along the Euphrates River) periodically raided Mesopotamian cities. The attacks on the Mesopotamian cities are stated in the Epic to be the work of the Sut�. The Assyriologist Wilfred Lambert held that the reign of Adad-apal-iddina fits the account of the Epic quite well. It has also been proposed that the epic was composed following the recovery of the statue of Marduk from Susa by Nebuchadnezzar 1 after its removal by the Elamite king Kutir-Nahhunte. This event is dated to the 12th-century BCE. Circa 1160 BCE King Kutir-Nahhunte invaded Mesopotamia and took the city of Babylon. Included amongst the items he brought back from Babylon was the Code of Hammurapi. Circa 1120 BCE King Nebuchadnezzar 1 conquered Elam. (However, for the possibility of an additional astronomical interpretation of the story, see Mesopotamian Planetary Astronomy-astrology by David Brown (2000, Pages 256-257).)

The “changes in symbolism” argument used by the authors of Hamlet’s Mill to claim that the shift from an “Age of Twins” to an “Age of Taurus” to an “Age of Aries” to an “Age of Fish(es) is identifiable suffers from the dual burden of wishful thinking and absence of evidence. “At time Zero (say, 5000 B.C. – there are reasons for this approximate date), the sun was in Gemini; it moved ever so slowly from Gemini into Taurus, then Aries, then Pisces, which it still occupies and will for some centuries more. The advent of Christ the Fish marks our age. … The preceding age, that of Aries, had been heralded by Moses coming down from Mount Sinai as “two-horned,” that is, crowned with Ram’s horns, while his flock disobediently insisted upon dancing around the “Golden Calf” that was, rather, a “Golden Bull,” Taurus (Hamlet’s Mill, Pages 59-60).” (Interestingly, Hertha von Dechend, though raising the possibility of such an interpretation in her M.I.T. seminar notes, stated she did not favour this particular explanation.) Additionally, the voyage of the Argonauts for the Golden Fleece (of a ram) introduces the “Age of Aries” (Hamlet’s Mill, Page 318).

Other writers like to add in further examples such as the slaying of the Cretan Minotaur symbolising the end of the “Age of Taurus.” The cult of the Apis bulls in Ancient Egypt is held to represent the “Age of Taurus” and the Amun cult in Egypt is held to represent the “Age of Aries.”

The “changes in symbolism” argument, which goes back to the 19th-century, easily collapses with only a few criticisms. The date of Moses is usually given as circa 1500 BCE. There was no zodiac circa 1500 BCE. so it is impossible to have zodiacal world ages at this early date. Certainly there was no scheme for equally dividing the ecliptic, or other established convenient frame of coordinates, at this early date. As such equally timed changes in “world ages” is out of the question. In the case of Moses having horns we have a simple translation error. The Hebrew root KRN can be keren meaning “horn” or karan meaning “radiant.” When the Hebrew bible was translated into Latin the Hebrew KRN was mistranslated as “horned” (and so instead of Moses’ face being radiant it was horned). It has not been demonstrated that the search by Greek heroes for the “Golden Fleece” has anything to do with a constellation or astronomy. The Golden Fleece of the Argonautica may be connected with the holy fleece of Hittite ritual. It was a Hittite custom to hang a container made from the skin of a sheep from a sacred evergreen tree in the centre of a grove. The fleece were decorated with gold and the sheep skin container filled with offerings to their gods/goddesses. However, it is common to interpret the Argonautica as an adventure story recalling how early Greek mariners searched for new territories to expand Greek trade.

The Cretan Minotaur was half bull and half man. Taurus is simply a truncated bull. Why exactly the Cretan Minotaur should represent the “zodiacal” bull (Taurus) is never explained. Why Theseus killing it should represent the end of the “Age of Taurus” is also never explained. Nothing at all is known of Minoan constellations so no proof of any intended association with a Minoan bull constellation is possible. The Apis bull was believed to be the incarnation of the Egyptian god Ptah. It has not been demonstrated that the Apis bull has anything to do with astronomy. The identification of native Egyptian constellations is mostly uncertain. The Apis bull has never been linked with a native Egyptian bull constellation (at any time – let alone during a supposed “Age of Taurus”). Chronologically the cult was more popular during the supposed “Age of Aries” than it was during the supposed “Age of Taurus.” The Egyptian god Amun was originally frequently depicted as the Nile goose and later more frequently depicted as a ram, or as a ram-headed man. However, from the cult’s beginning’s Amun could be depicted as either a Nile goose or as a ram, or as a ram-headed man. Chronologically the cult originated in the supposed “Age of Taurus.”

The concept of precession-based zodiacal “world ages” is largely a 19th-century Theosophical concept invented by the occultist Helena Blavatsky. Nick Campion identifies that the concept draws “partly on Hesiod’s sequence of ages outlined in the Works and Days, the Hindu Yugas, some 19th century studies of comparative religion and Madame Blavatsky’s own theory of racial and spiritual evolution (Hastro-L, 13 April, 2000).” (However, the concept of precessional “world ages” can also be traced back to Origine des tous les cultes: ou, Religion universelle by Charles Dupuis (1794).) Additionally, the constellations are all of uneven size and we have no knowledge of the boundaries of any early constellations. We have no knowledge of even the boundaries of the Greek constellation scheme of Aratus of Soli circa 275 BCE.

If precession was known in early Babylonia we could reasonably expect it to be recognised in some form of the mathematical astronomy that developed and/or later calendar systems. (The Babylonians did identify and record some long-term astronomical cycles such as the synodic periods of the moon and planets.) It would seem that the Babylonians were limited by their lack of interest in theoretical astronomy and they had no geometric scheme to assist them. (See, however, Lengths, Widths, Surfaces: A Portrait of Old Babylonian Algebra and its Kin, by Jens H�yrup (2002), for the proposal that Old Babylonian algebra was not numerical but geometrical in nature.) They simply applied arithmetic to data that the later Greeks would apply geometry to. The concept of precession could be realistically discovered and described only when geometric concepts had been developed. This was only achieved by the Greeks. The earliest Greek geometry can be traced to Thales of Ionia (635-543 BCE) and Pythagoras of Ionia (582-496 BCE). (The rudiments of practical geometry are, however, found in the earlier mathematical traditions of Babylonia and Egypt.) It can be confidently stated that the phenomenon of precession was not identified by the Babylonians (and so it is out of the question that it was understood as a systematic continuous variation (i.e., that all stars have slow continuous motions parallel to the ecliptic) and that the rate of precession was measured).

Appendix 1: The Myth of Knowledge of Precession in the Eddas

It is not unusual to hear the claim repeated that knowledge of precession appears in the Eddas (a collection of old Norse poems and tales dating circa 10th-century CE). The claim simply rests on verse 23 of the poem Grimnism�l in the Eddas. At Ragnarok (“end of the world”) out of each of the 540 doors of Valholl (“hall of the dead” or “hall of the slain”) will come 800 warriors. (It is also pointed out that in verse 24 of the poem there are 540 rooms (or “floor-rooms”) in Thor’s palace of Bilskirnir.)

Stanza 23 of Grimnism�l has the descriptive lines:

Five hundred doors and forty,

Think I there at Valholl;

Eight hundred einhergar go out one door,

When they go to fight with the wolf.

Valholl was the largest building in Asgard, the celestial realm of the Norse gods/goddesses. The number of doors is multiplied by the number of warriors emerging from each door to achieve an end number of 432,000 warriors. (This calculation and the resulting number of 432,000 is not in the Eddas.) The claim is then made that the number 432,000 refers to a precessional “great year.”

It is correct that according some sources Valholl has 540 doors each wide enough for 800 warriors. It is correct that the 540 rooms (or “floor-rooms”) in Bilskirnir can match the version of 540 doors of Valholl. However, I do not recall any “associated number” such as 800 (or 960) warriors (or whatever) connected with Bilskirnir. Also, according to other sources Valholl has 640 doors each wide enough for 960 warriors. Hence out of the medieval tale we can multiply the former figures and get the resulting number 432,000 or we can multiply the latter figures and get the number 614,400. The figure of 432,000 may be linked with the Babylonian doctrine of “cosmic recurrence” (i.e., a “great year” linked to “powerful” conjunctions, not a precessional “great year”). I have never seen the figure 614,400 touted as belonging to either. (A prime candidate for uncritically promulgating this sort of arithmetic is the Jungian mythologist Joseph Campbell in his (for example) book The Masks of God: Occidental Mythology (1964, Page 459).)

The supporters of knowledge of precession in the Eddas seem to have no knowledge of the old Germanic system of calculation. In the old Germanic system of reckoning the “long hundred” had the value of 120. In all likelihood the “five hundred … and forty” and the “eight hundred” have the Germanic “long hundred” value (not the decimal value 100). Hence 640 doors and 960 warriors. Even orthodox writers may or may not indicate knowledge of the old Germanic system of calculation. Norse Mythology by John Lindow (2001) simply gives 540 doors and 800 warriors. World Mythology by Donna Rosenberg (2nd edn., 1994) simply gives 640 doors and 960 warriors. Myth and Religion of the North by Edward Turville-Petre (1964) gives both 540 (or 640) doors and 800 (or 960) warriors. An important discussion of the issues by Magnus Olsen appeared in (the Danish language) Acta Philologica Scandinavica, Volume VI, 1931-1932. (The particular paper was later included in his collected papers Norrone studier (1938).) See also “Numeracy and the Germanic Upper Decades” by Carol Justus (Journal of Indo-European Studies, Volume 24, 1996).

References to Valholl can thus have the numbers 540 and 800 or 640 and 960. References to Bilskirnir simply have the number 540 but not 640 nor 800 or 960. Some people are keen to multiply 540 by 800 but not 640 by 960.

For the number 540 Vincent Hopper suggested (Medieval Number Symbolism, 1938, reprinted 1978) that the Medieval Norse (1) had an idealised 360 day year calendar (adjusted by intercalation), (2) calculated time by half years; and (3) 540 denotes a calendar cycle of 3 half years (winter-summer-winter). It seems we may be playing with nothing deeper than mundane calendar-based numbers.

A further (standard) study of Valholl is Walhall by Gustav Neckel (1913). His opinion was the “five hundred … and forty” doors intends to express nothing more than a large number and was perhaps influence by Norse knowledge of the numerous doorways (and vomitoria) of the Roman Colosseum (Coliseum). There were 80 entrances at ground level. However, the Colosseum incorporated a number of vomitoria – passageways designed so that the venue could quickly disperse people into their seats (in 15 minutes), and evacuate them abruptly (in 5 minutes).

Appendix 2: The Recognition of Precession in China

The earliest archaeological evidence of a Chinese calendar appears on the oracle bones of the late 2nd-millennium BCE. The demonstrate a 12-month lunisolar year with the occasional arbitrary intercalation of a 13th- and even 14th-month. However, Chinese historical records place the origin of a lunisolar calendar (of 366 days) to circa 3000 BCE. The development of a calendar in China was closely related to the development of astronomy and the needs of agriculture. (China was largely an agricultural society.)

The earliest tentative awareness of precession in China took hold in the Hou Han (= later Han) period. (The later Han period is also now referred to as the Eastern Han Dynasty and spanned from 25 to 220 CE.) During this period it was quite widely recognised that the calendar altered (i.e., became unreliable) every 300 years. That is, every 300 years there was a requirement to use a new calendar. Multiple mentions of the fact that the calendar was only good for 300 years appears in the multiple volumes of the Hou Hanshu (= Book of the Later Han) by the historian Fan Ye (flourished 398-445 CE).

The discovery of the precession of the equinoxes in China can be attributed to the scholar Y� Hsi (flourished circa 307-338 CE) circa 320 CE who discussed it in his book, the An Thien Lun written 336 CE. (The book discussed whether the motions of the heavens were stable.) Y� Hsi obtained a value of about 1 degree in 50 tropic years for the precessional movement.

The brilliant scholar Zu Chongzi (420-500 CE) created the Daming Calendar (some sources say promoted his father’s calendar ) which took precession into account for the first time. The most thorough and comprehensive calendar in the history of China was the Dayan Calendar compiled in the Tang Dynasty (616-907 CE) by the monk Yi Xing.