Some Preliminaries
Hellenistic Astrology has three branches:
Universal, that is concerning large groups of peopl, This might refer to their traditional political unit was the city state, such as Athens or Sparta. The Greeks referred to a city state as a Polis - from which we get out derivative words such as political and police. Universal Astrology could be appied to other groupings, such as the egyptians or babylonians or persians. This form of Astrology was directly borrowed from the babylonian omen Astrology but was modified by the Greeks. As it was borrowed before the inception of the horoscopic chart, I don't think that the Hellenistic Astrologers would use it in the same way as we use Mundane Astrology today. Universal Astrology also covered natural Astrology such as predicting the weather or the annual flood of the Nile.
Natal Astrology - this is clearly the type that we've been dealing with up to now, and no doubt will continue in this thread, so I'm not saying any more about it at this stage.
Katarchic Astrology - this is concerned with events and their outcomes. It can be used to examine events that have already happened - just as we do today and it can be used to choose or elect propitious times to carry out certain work or tasks. I've not looked at Katarchic Astrology in this thread, yet. It is something that I intend to do. having arranged with my daughter to buy me the text by Hephaistio of Thebes, as a Christmas present
So it's likely to come after Christmas in the main LOL
The fourth branch of Astrology that I practice on this site is Horary. There's some debate as to whether Horary existed in Hellenistic times but the dominant answer at the moment is that it did not and it's probably an eighth century development by the persians.
The next thing I want to mention here is the use of Greek terms. I deliberately left them out of the early part of this thread because I didn't want to confuse people too much. It's bad enough introducing ideas which seem alien to modern astrologers without changing all the accepted technical terms. Robert Schmidt who I referred to earlier on and whose approach I tried to use does not use modern terminilogy in his translations. So for example instead of Mercury, he refers to the direct translation, the star of Hermes. Instead of the Sun and the Moon there's Helios and Selene. I'm thinking about that but I'm not sure yet. Exactly the same issue comes up with the Signs. Do I refer to Aries or to the Ram?
However there are some terms which I think I really do need to adopt. The term 'Sign' has replaced the Greek word that translates as 'house' So when a Hellenistic Astrologer refers to the House of the Star of Ares, he's not referring to something like Mars ruling the fifth house. What he means is either the modern sign of Aries or the modern sign of Scorpio - that is the sign of the zodiac that Mars rules. Chris Brennan suggests substituting the word 'domicile' instead of house, so one of the domiciles of Mars is Scorpio. I'm used to this way of referring to signs because it's terminology that Lilly uses from time to time. So from now on I'll use 'domicile' instead of 'sign'.
The 12 houses of modern and indeed medieval Astrology were referred to as 'topos' or place. It's the Greek word from which we derive the English words 'topic' and 'topical' and that's important. The Hellenistic houses were used to examine the 'topics' in a person's life, such as relationships or children or career. So I'll start to use the word 'place' instead of 'house'.
Lastly on terminology, one thing that threw me about Schmidt's work was the use of terms such as 'goaded' when examining the fitness of a planet. It's one of the translations of the Greek word Kentron, which also translates as 'pivot'. The word kentron is used to describe a 'place' that we would term angular - first, fourth, seventh tenth 'place'. the translation of kentron as 'goad' is in the sense of a cattle prod or prodding something or someone with a stick in order to get them to do something. So Angular houses are both pivotal - the direction of celestial rotation changes at them, but also planets there are impelled to act. I think that connection with action is one a modern astrologer would recognise but perhaps the would not realise it derives from the word used to descibe an angular house - it's been essential property from the start.
The seven traditional planets were descibed as 'planetes asteres' (literally wandering stars). There seems to have been debate from fairly early on as to whether planets were 'signs' in the sense of simply signifying something or causes ', a much stronger association of planet with event. I've seen a lot of scientists criticise Astrology by saying that it's preposterous that a planet through its actions can cause something to happen. You need to realise that whilst Ptolemy did talk in those terms many of the other did not. For Valens the planets are significators or 'omens' of the event or nativity. There's no causal relationship whatsoever, except that they both might share a common cause, the will of God.
The last point I'll make in this post is about the zodiac used. There's quite a bit of debate about whether the Hellenistic Astrologers used the tropical zodiac based on the seasons (as used in modern Western Astrology) or the Sidereal Zodiac based on the position of fixed stars, as is the case in Jyotish (or Vedic Astrology). These are important distinctions because of the phenomenon of precession - if you consult an Astrologer who uses Jyotish, he's tell you that the Sun is currently in the sign of Scorpio, not Sagittarius. The difference is about 24 degrees offset - i'e. only the last six degrees of the tropical sign of Scorpio is in the sidereal sign of Scorpio (where it forms the first six degrees).
The Hellenistic Astrologers were aware of precession but 2,000 years ago the two zodiacs were virtually in synch, that is tropical Scorpio and sidereal Scorpio were largely co-incident. Therefore to them it was not a problem that they needed to deal with. However their descriptions of the zodiac 'domiciles' used both tropical and sidereal references. They clearly did use the quadruplicities/modalities of Tropical (Cardinal). Solid (Fixed) and Double bodies (Mutable) to describe the domiciles. That division only makes sense in the context of reference to the Tropical Zodiac (incidentally the word Tropical comes from the Greek Tropos meaning a turning point - the Tropical domiciles were where the season turned from one to another.
However they also refer to fixed stars or constellations in the domiciles and can give those significance. That's clearly a sidereal reference. Earlier this week I did a horary reading in which the fixed star Castor came into use - for the siderea zodiac it's in Gemini, as I think most of you know. However in the Tropical zodiac it lies in Cancer. An Astrologer might want to use that link betwen one of the Gemini Twins and the sign of Gemini - whilst it can be done using the tropical zodiac the double emphasis on Gemini (pardon the play on words) is lost and the interpretation of Castor and Cancer just doesn't have that certainty to it.
It was Ptolemy who started the trend towards the Tropical Zodiac becoming the Western norm but it's not clear how widely he was followed until the issue of precession really became important after the Hellenistic period.