Did Ptolemy understand the precession of the Equinoxes?
- Thread starter Michael
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JUPITERASC
Well-known member
"The beginnings of the signs, and likewise those of the terms, are to be taken from the equinoctial and tropical points. This rule is not only clearly stated by writers on the subject, but is also especially evident by the demonstration constantly afforded, that their natures, influences and familiarities have no other origin than from the tropics and equinoxes, as has been already plainly shown. And, if other beginnings were allowed, it would either be necessary to exclude the natures of the signs from the theory of prognostication, or impossible to avoid error in then retaining and making use of them; as the regularity of their spaces and distances, upon which their influence depends, would then be invaded and broken in upon."
Ashmand, J. M. Ptolemy's Tetrabiblos. Astrology Classics. p. 37 (I.XXV).
Ashmand, J. M. Ptolemy's Tetrabiblos. Astrology Classics. p. 37 (I.XXV).
Hipparchos knew of precession-Ptolemy followed Hipparchos work: yes, Ptolemy was in all likehood aware of what Hipparchos knew about the subject of precession. It is decidedly possibile-perhaps even probable-that Ptolemy realized that the zodiacal star constellations would displace out of their respective signs-and Ptolemy clearly gave emphasis to the "divisions of the Earth" AS SIGNS, over the zodiacal constellations then (2nd century CE) currently occupying those places (those SIGNS)...
Proponents of tropical astrology will concoct any excuse to maintain the astrological fallacy of the "tropical zodiac". Maybe it's because that's what they've learned (so it's an ego thing). Or maybe they just don't understand what precession is (which is what one professional astrologer confessed to me). Before Ptolemy, the zodiac was NOT defined by the spring equinox. Before Ptolemy, no one “fixed” the zodiac to the equinoxes. If Ptolemy knew about precession, then either he ignored it (because he was focusing on his own era, when 0˚ Aries actually did coincide with the vernal point), or he didn't understand it well (after all, he merely compiled his information from earlier sources; i.e., he didn't "discover" anything new). Or, maybe he wanted to be a renegade and say something different, just to be gauche. Who knows? In any case, his book Tetrabiblos is the source of the current confusion/delusion.
Here's the truth:
1) Precession is real. Everything is moving, nothing is stationary. That's why the ancients kept such close track of the stars--they knew that everything moved and needed to be accounted for.
2) The vernal point (upon which tropical astrology bases its "zero-point Aries," which currently is not even in Aries) is a point in space not connected to anything physical or anything at all. It too is constantly shifting.
3) The sidereal zodiac corresponds with the actual constellations (actual physical stars). The stars in those constellations are all relatively close to our Solar System:
- half of them are less than 100 light years away (which is close, relatively speaking);
- most of the other half are less than 380 light years away (also relatively close).
- A couple of the zodiac stars are about 1,000 light years away (which is also relatively close, considering our Milky Way is ca. 100,000 light years across). Interestingly, all of these are located in Capricorn and Aquarius.
The astrological signs that have been assigned to those actual, real zodiac constellations go back millennia--long, long, long before Ptolemy. No one knows what "causes" astrological power, i.e., what validates astrology and astrological signs. My guess: It's the gravity and the energy from those close zodiac stars that cause the effects. But one thing is for sure--people who continue to push the tropical fallacy are just adding to the argument against the validity of astrology, because their argument is literally based on empty space.
Here's the truth:
1) Precession is real. Everything is moving, nothing is stationary. That's why the ancients kept such close track of the stars--they knew that everything moved and needed to be accounted for.
2) The vernal point (upon which tropical astrology bases its "zero-point Aries," which currently is not even in Aries) is a point in space not connected to anything physical or anything at all. It too is constantly shifting.
3) The sidereal zodiac corresponds with the actual constellations (actual physical stars). The stars in those constellations are all relatively close to our Solar System:
- half of them are less than 100 light years away (which is close, relatively speaking);
- most of the other half are less than 380 light years away (also relatively close).
- A couple of the zodiac stars are about 1,000 light years away (which is also relatively close, considering our Milky Way is ca. 100,000 light years across). Interestingly, all of these are located in Capricorn and Aquarius.
The astrological signs that have been assigned to those actual, real zodiac constellations go back millennia--long, long, long before Ptolemy. No one knows what "causes" astrological power, i.e., what validates astrology and astrological signs. My guess: It's the gravity and the energy from those close zodiac stars that cause the effects. But one thing is for sure--people who continue to push the tropical fallacy are just adding to the argument against the validity of astrology, because their argument is literally based on empty space.
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We don't require excuses. We need only rely on what is written.
Very obviously, you have confused and conflated signs with constellations. They are not the same thing. The constellations do move through the procession of the equinoxes. The signs are merely images, which is what the ancient texts say they are, and they never say they're constellations.
Glad we got that straightened out.
Monk
Premium Member
It is wrong that all stars appear to move due to precession one degree every 72 years, that only happens with stars that sit on the ecliptic, like Regulus, the vast amount of the other stars move at a different rate.
When we used the Julian Calendar when Sirius rose with the Sun, it would stay in the same position for thousands of years, because of quote below:-
"Mechanics
The ancient Egyptian civil year, its holidays, and religious records reflect its apparent establishment at a point when the return of the bright star Sirius to the night sky was considered to herald the annual flooding of the Nile.[2] However, because the civil calendar was exactly 365 days long and did not incorporate leap years until 22 BCE, its months "wandered" backwards through the solar year at the rate of about one day in every four years. This almost exactly corresponded to its displacement against the Sothic year as well. (The Sothic year is about a minute longer than a Julian year.)[2] The sidereal year of 365.25636 days is only valid for stars on the ecliptic (the apparent path of the Sun across the sky) and having no proper motion, whereas Sirius's displacement ~40° below the ecliptic, its proper motion, and the wobbling of the celestial equator cause the period between its heliacal risings to be almost exactly 365.25 days long instead. This steady loss of one relative day every four years over the course of the 365-day calendar meant that the "wandering" day would return to its original place relative to the solar and Sothic year after precisely 1461 Egyptian civil years or 1460 Julian years.[1] "
The error in the Julian Calendar are three leap days every 4 hundred years which is also applied to Sirius!
https://en.wikipedia.org/wiki/Sothic_cycle#Mechanics
When we used the Julian Calendar when Sirius rose with the Sun, it would stay in the same position for thousands of years, because of quote below:-
"Mechanics
The ancient Egyptian civil year, its holidays, and religious records reflect its apparent establishment at a point when the return of the bright star Sirius to the night sky was considered to herald the annual flooding of the Nile.[2] However, because the civil calendar was exactly 365 days long and did not incorporate leap years until 22 BCE, its months "wandered" backwards through the solar year at the rate of about one day in every four years. This almost exactly corresponded to its displacement against the Sothic year as well. (The Sothic year is about a minute longer than a Julian year.)[2] The sidereal year of 365.25636 days is only valid for stars on the ecliptic (the apparent path of the Sun across the sky) and having no proper motion, whereas Sirius's displacement ~40° below the ecliptic, its proper motion, and the wobbling of the celestial equator cause the period between its heliacal risings to be almost exactly 365.25 days long instead. This steady loss of one relative day every four years over the course of the 365-day calendar meant that the "wandering" day would return to its original place relative to the solar and Sothic year after precisely 1461 Egyptian civil years or 1460 Julian years.[1] "
The error in the Julian Calendar are three leap days every 4 hundred years which is also applied to Sirius!
https://en.wikipedia.org/wiki/Sothic_cycle#Mechanics
JUPITERASC
Well-known member
Monk
Premium Member
Julius Caesar used 25 March as the Vernal Equinox, quote below:-
This drift induced Pope Gregory XIII to establish the modern Gregorian calendar. The Pope wanted to continue to conform with the edicts of the Council of Nicaea in 325 AD concerning the date of Easter, which means he wanted to move the vernal equinox to the date on which it fell at that time (21 March is the day allocated to it in the Easter table of the Julian calendar), and to maintain it at around that date in the future, which he achieved by reducing the number of leap years from 100 to 97 every 400 years. However, there remained a small residual variation in the date and time of the vernal equinox of about ±27 hours from its mean position, virtually all because the distribution of 24 hour centurial leap-days causes large jumps (see Gregorian calendar leap solstice)."
en.wikipedia.org
We would still have 25 March as the Vernal Equinox if the Gregorian Calendar had corrected all the way back to the start of the calendar in 0045BC, however they only took error days out up to the Council of Nicaea, which also means the original date of the Winter Solstice would have been 25th December, an interesting date to think about!
Date
"When Julius Caesar established the Julian calendar in 45 BC, he set 25 March as the date of the spring equinox;[15] this was already the starting day of the year in the Persian and Indian calendars. Because the Julian year is longer than the tropical year by about 11.3 minutes on average (or 1 day in 128 years), the calendar "drifted" with respect to the two equinoxes – so that in 300 AD the spring equinox occurred on about 21 March, and by the 1580s AD it had drifted backwards to 11 March.[16]This drift induced Pope Gregory XIII to establish the modern Gregorian calendar. The Pope wanted to continue to conform with the edicts of the Council of Nicaea in 325 AD concerning the date of Easter, which means he wanted to move the vernal equinox to the date on which it fell at that time (21 March is the day allocated to it in the Easter table of the Julian calendar), and to maintain it at around that date in the future, which he achieved by reducing the number of leap years from 100 to 97 every 400 years. However, there remained a small residual variation in the date and time of the vernal equinox of about ±27 hours from its mean position, virtually all because the distribution of 24 hour centurial leap-days causes large jumps (see Gregorian calendar leap solstice)."
Equinox - Wikipedia
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JUPITERASC
Well-known member
https://en.wikipedia.org/wiki/Equinox#cite_note-19
Equinox - Wikipedia
Thanks Monk for clarifying
.