None of the divisions of the Zodiac comes to mind as naturally and intuitively as the 12th division called dvadashamsha in India and dodekatemoria in the Hellenistic tradition. Henceforward I will call them the 12th parts. If I was told to divide a sign into many parts, the division into 12 parts would be my first thought and I would also want those twelve parts to be Zodiacal signs, so that I would have a micro Zodiac within one sign. Of course I’m not the first person to think about this and the 12th parts were common to both, the Indian and the Hellenistic astrological tradition and are the same in both traditions.



Although the 12th parts are calculated by a multiplication method like the harmonic divisions there is a difference – the micro Zodiac of the 12th parts does not begin with Aries in every sign, but instead it begins with the 12th part of the sign itself. Thus, we don’t have a natural sequence of the signs as we would have in the 12th harmonic division.

Picture no.1: The 12th parts

The calculation method for calculating the 12th parts to a degree is as follows:

  1. See the degrees and minutes of a planet.
  2. Multiply the degrees by 12.
  3. Multiply the minutes by 12 and convert the result into degrees.
  4. Add the result to 0 degrees of the sign the planet is in.
  5. You arrive at the exact 12th part position.

As you see the calculation is very similar to the calculation for the harmonic divisions, but we don’t count the absolute longitude from 0 degrees Aries, but from 0 degrees of the sign the planets is in. Likewise, we don’t add the result to 0 Aries, but to the beginning of the sign.



Wouldn’t it make more sense if the micro Zodiac would simply start with Aries and end with Pisces in every sign? Why did the ancient astrologers choose to do it in this way? In order to be able to answer this question we first have to look at the harmonic version of the 12th parts, where the order of the signs is natural.

Picture no.2: The 12th harmonic

As with any harmonic division, here too, we get a polygon – a dodecagon if we connect the twelve instances of the same sign. If we approach this harmonic 12th parts version through geometrical relationships we face a challenge, because in a dodecagon all the major astrological aspects are present. We have the first interval of 30 degrees, a semi-sextile and then sextile, square, trine, quincunx and opposition, so all of them are included. To many astrologers, the harmonic 12th parts seem redundant, because of all the aspects being present and this might have been the reason why the ancient astrologers opted for the non-harmonic version which breaks the natural sequence of the signs and were concerned with the division of the signs themselves instead of harmonic division of the circle.

The other possibility is that an error was involved and I always leave space for errors as I’ve seen them sneak into the texts a few times and the ancient astrologers were not free of erring.  There is an error that I’ve made myself when I wanted to calculate a harmonic 12th part for the first time. The error is, that one easily overlooks the fact that it should be calculated from 0 Aries and not from 0 degrees of the sign the planet is in. What I got with my calculation were the regular 12th parts instead of the harmonic ones. It is a mistake that happens quite quickly and I leave it open for this possibility although the 12th parts as we know them have a long tradition. That said, I use the regular version every day and I have to say that it speaks rather well.



In Brihat Parashara Hora we read that the 12th parts should be looked for parents. As I’ve demonstrated with the theme of children for the saptamsha, here, too parents should be taken as a guideline and we should think in terms of patterns that existed before we were born, so through the 12th parts we can see the hidden, underlying nature of what is manifested. Hellenistic author Firmicus Maternus tells us in his Mathesis:

»Now I shall briefly set forth what you want to know about the dodecatemoria. Some people think that from these the whole essence of the chart can be found and they claim that whatever is hidden in the chart can be revealed by the dodecatemoria.« (Liber secundus XIII)

»When Saturn is located in these houses, carefully observe his degree so that you may find in what house and in which terms the dodecatemorion is; from this information you may discover the whole power of Saturn.« (Liber Tertius, II)

»Look carefully at the dodecatemorion of the Sun and its terms so that the teaching of this book may not lead you into any error.« (Liber Tertius, V)

»Look carefully at the dodecatemorion of the Moon and its terms. For whatever is concealed in the chart in the general combination of the planets is made obvious in the dodecatemorion and its terms. If you wish to set forth the whole essence of the forecast from the dodecatemorion you will not be deceived. The Babylonians attribute all the forecast to the dodecatemorion; but Ptolemy to the antiscia, and we to both.«

Firmicus Maternus stresses the importance of the 12th parts and their positions in the bounds very much. It is interesting that he advices looking at the bounds. This cannot be done unless one imports the 12th part positions of planets and points into the main chart and looks into which term they fall. We find the same in Yavanajataka:

»In (each) sign there are dvadashamshas (dodecamoria) which fill the sign with their own influences. There are subtle modifications in respect to height or depth of action when (their) influences are combined with those of the terms (trimsamsas).« (Chapter 1, verse 36, David Pingree’s translation)

Why is the placement of 12th parts in the bounds or trimsamshas so important? In PART 3 I’ve shown how trimsamshas, being ruled by the five non-luminaries have a relationship with the Sun and Moon ruled horas. It is natural to wonder how a division that excludes the Sun and the Moon connects to them. The 12th parts have a 1/12 relationship which is roughly a relationship of the Sun and the Moon in their Soli-Lunar cycle. Thus, we judge the 12th part positions of planets and points by their placement in the bounds or trimsamshas.

Yavanajataka also defines the influence of the 12th parts:

»The influence (of the planets) in the degrees of their exaltations is complete; in their navamshas, as in their mulatrikonas; in their dvadashamshas, as in their houses (signs); and in the degrees of their dejections or of their enemies, it is the least.« (Chapter 8, verse 1)

Some like to correlate the divisions with the houses and thus they connect the 12th parts to the 12th house, which can be valid since the nature of the 12th parts and the 12th house have much in common, 12th house being the house of ancestors, thought patterns and psychological complexes among other things.



It is important to note that while we usually consider Vedic astrology to be highly informative regarding the application of the vargas I actually don’t find that necessarily to be the case. It is true that Indian classical astrological texts introduce many different vargas, clearly more than what we find in the Hellenistic astrological texts. And it is also true that these texts introduce a lot of delineations for planets situated in each and every part, but I find it very interesting that it is in Hellenistic texts that we find more instructions on how to use the 12th parts and especially the bounds in a more technique oriented way (cousins of trimsamshas) as I’ve demonstrated in my article on the bounds.

In my article on the saptamsha I’ve used the same method of super imposing the varga positions on the main chart and this is how Hellenistic astrologers were using the 12th parts. When I first came to know about this method it seemed very strange and didn’t make much sense to me because I’ve been used to using vargas as either stand alone charts or as simple lists of varga positions, used for nothing else but dignity and seeing which planet is ruling that part. There is an endless debate going on regarding vargas as charts and astrologers are split on the matter. Some believe that varga charts are a modern invention and have no basis in the classical texts while others advocate the use of varga charts and try to find some rationale for it along with some evidence in the classics. To my knowledge Jaimini Upadesha Sutra is the only astrological text of India that hints towards the use of varga charts and not only varga lists. Other classics clearly don’t suggest drawing vargas as charts anywhere.

What we find in Hellenistic astrology might be the missing link and could bring the two camps together. Here the 12th part positions are calculated to a degree as shown in the second chapter of this article and the positions are simply drawn either around the main chart or even inside it, along with the main positions, but if we do this, we need to make sure that we somehow differentiate between them.  Basically we do have a varga chart, as we’ve drawn the varga positions in the signs, so we do have spatial relationships, but we don’t read these positions independently of the main chart. Instead, we look at how a planet is influencing another planet or point via its 12th part position, like influencing something physically manifested through its subtle, invisible body, so to speak. We also don’t define a new set of 12 houses, but use the houses of the main chart.

In the two examples below I will try my best to demonstrate how the Hellenistic astrologers approached the matter. For this purpose I will focus more or less on their career or vocation. The 12th part positions are in the wheel, but further to the center. The main positions are close to the circle showing degrees.

The above is a horoscope of a painter. It has Virgo rising with the ascendant in the bound of Mercury, so we have a really powerful rulership of Mercury over the ascendant. Mercury is in a form producing, Venus ruled Taurus in his own bound in the 9th house together with the MC, but not tightly conjunct, retreating from it, but is still close enough. Venus is advancing towards an angle, exalted and in her own bound in the 7th house. Jupiter, her sign lord is exalted in the 11th house in the bound of Mars. We see that she is a very skillful person (Mercury), highly artistic (Venus and Jupiter), with many interests and talents (Mercury), spiritually inclined (Mercury in the 9th) and that this plays a significant role in her artistic expression since there is a strong connection of Mercury in the 9th and Venus in the 7th by Venus overcoming Mercury with a sextile aspect and is receiving him.

Now, let’s look at the 12th parts. Mercury has his 12th part in Libra in Jupiter’s bound which brings Mercury also into the area of finance and gain. Venus has her 12th part in Gemini 10th house and her own bound again. Mercury and Venus are now further bound by mutual reception by 12th part. The Moon exalts by 12th part in the 9th and is also well situated by her main position in the 4th, Sagittarius in a mutual reception with Jupiter. Overall this chart shows plenty of art, ideas, moving in artistic and spiritual circles and also an underlying agenda of earning livelihood through art.  The exaltation of Jupiter is lessened a bit by his 12th part position in the 12th house and the Sun, Lot of Fortune and the 12th part of Midheaven all fall in the unfortunate 8th house, so all the good stuff indicated has some difficulty in manifesting, especially with the Sun being in an idle place and also conjunct Saturn and Lot of Spirit in Capricorn by its 12th part position, bringing delays and success in the long run.

The above is a horoscope of a cardiologist. It has Gemini rising and the ascendant is in a bound of Mercury. We have Mars, the 6th and 11th lord in the 1st house in a bound of Jupiter which gives Mars a more pleasant tone, especially when the chart is diurnal and Mars is the out of sect malefic. This is a very skillful and knowledgeably Mars. Mars is advancing towards the ascendant thus he is very loud. This alone indicates that 6th house matters are a very much present in her life. Lot of Fortune is also there in the 1st house in Jupiter’s bound. Jupiter is exalted in the 2nd house and rules the 10th whole sign house. Both Sun and Moon are in the 12th, Taurus. Moon gets some help from her exaltation, but nevertheless we have three self factors, ascendant, Sun and Moon in the 12th, hidden place along with the Lot of Spirit. The Sun and Mercury are in the bound of Venus and Venus is exalted in the 10th house, albeit in a malefic bound of Saturn. Saturn is in the 6th house of diseases, aspecting by opposition the 12th house stellium. Although we have the unfortunate 12th house placement there are factors that make up for that so her life was not extremely difficult, but she has been separated from her father for which there is still sadness present although she is now in her 3rd part of life. The 12th house as the house of hospitals and so much 6th house influences speaks well for her vocation. Of course, she was not spared from diseases and she survived cancer (8th lord Saturn in the 6th with Capricorn involved, which according to Jaimini Rishi is a sign connected with tumors and cancer).

What do the 12th parts have to say? The 12th part of the ascendant is with Saturn in the bound of Mars. So, even by 12th parts we have the 6th house connected with the 1st. Mercury and Sun remain in the 12th house, but fall in the bound of Mars. We can see that Mars has quite a lot of rulership in this chart. Mars is again under rulership of Mercury and falls in the bound of Venus which again makes him more beneficial. So much rulership of Mars with Mars being softened is something we would expect to see in a chart of a person dealing with cardio-vascular diseases. Mars pumps the heart and rules blood.

As always with such examples, we’ve mostly touched on the vocation, so I’ve left certain factors out, but I hope I’ve succeeded in the illustration of the 12th part use.

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