The ancients considered each planet as having a degree of ‘dignity’, which was a measure of how fully planets express their intrinsic (as per their inner essence, or spiritual quality) and extrinsic (described by the forms that are the manifestations of this essence) qualities.
To clarify the concept, astrologers considered planetary diginity to have two varieties - essential dignity, which rated how true a planet is to its essential nature through its position among the zodiac signs, and accidental dignity, which rated, amongst other things, the planets’ opportunity to act according to their position among the 12 houses. Essential dignity is given to a planet in its own sign, exaltation, triplicity, term or face, while accidental dignity looked for planets to be in or near the “pivots” or angular houses, in their Joy, in favorable houses, and in Sect. Swiftness of motion, combustion and other attributes were added later, but here we are considering accidental dignity as related to the houses and Ascendant.
The Ascendant also generated the Lots (Sahams). The Lots are an expression of the relationships between planets and the Ascendant (and therefore the houses of the horoscope), as positions and receptions show relationships between planets and zodiac signs. Lots were considered to be directly related to one’s fate: ‘the accident of birth’ determines one’s ‘lot in life’. It was said that a soul incarnates by choosing lots, and waiting until the planets and horizon align to manifest these lots: only then can one be born into a new human incarnation.
The lots express themselves through their disposition by sign and planet. Originally they were a system composed of the seven hermetic lots and the four lots of rank.
The lots of Basis, Exaltation, Fortune and Spirit were the lots of rank. They represented the relationship between day and night, Sun, Moon and the ascendant. They were related to sect (an accidental dignity related to the diurnal sphere) and the major cycles of the Sun and Moon, including the lunation cycle, eclipse cycles and other measures of celestial time as revealed by ancient calendric systems. Little survives as to their proper (or for that matter common) use, but I have found that basis has a lot to do with a person'e confidence and security, while exaltation seems to point to how one is received by the world.
The seven Hermetic lots were based on the five visible planets and the Sun and Moon. In fact, fortune and spirit were a part of both groups, and the other five planetary lots expressed the relationship between the ascendant, the planet in question, and the lot of fortune or spirit, depending on the group to which they belonged. In fact, the curious relationship between the construction of the Hermetic lots and the Kabbalistic tree of life is the subject of research I am writing and hope to have in publication soon.
The way in which the Hermetic lots were used is reminiscent of (but not identical to) many of the techniques of Hindu astrology. Their 'releasing' and 'profection' or predictive periods allowed them to express themselves through time, sequentially by zodiac sign, while the planets carried the significations of the lots. This brilliant methodology served to link accident and essence, fate and destiny, spirit and form.
The misunderstanding of the system, and its consequent reinvention by Islamic authors is probably due to Ptolemy. He attempted to render the methods of his time into what he conceived of as a ‘scientific’ approach, but although he was a great compiler of information, there is no evidence that he had anything other than theoretical experience with astrology. A lot of technique was lost or changed because of his personal biases. He either did not understand the time-dynamic view of the horoscope, or took a philosophical objection to it, and therefore, the west lost some of the most powerful techniques of the system of Hermes.
Everyday the 12 signs carry the planets with them as they rise and set – this is called the Diurnal motion of the heavens. The signs rise from the Ascendant to the Midheaven, and then begin to descend until they reach the Descendant, and continue until the Lower Heaven is reached, at which point they begin to rise again. The places at which they change their relationship to the horizon, and the places at which they change status from ascending to descending were considered to be of tremendous significance, like a daily analogue of the annual Solar cycle that hinges on the Solstices and Equinoxes. These points were called “Kentrons” or “pivots” by the Greek astrologers (Vedic astrologers call them “Kendras” or corners).
It is sometimes a little hard to see when looking at a chart on paper, but if you stand outside this principle upon which the houses are based becomes simple – the Eastern and Western horizons and the meridian (the North/South axis) remain fixed (from our perspective) and the heavens apparently move across them. The whole principle of the houses rests on this observation.
The houses on either side of the pivots are related to them in a very specific way. The declines, or cadent houses, "carried" planets away from the pivot point. Declines are the signs that rise, set etc. immediately before the sign in question: consider if Leo were the Ascendant – Cancer would be the decline, and planets in Cancer have now traveled upwards, not away from Leo, but away from the Ascendant.
The succedent houses were the ‘bearing’ or ‘supporting’ places, where planets moving away from a pivot point by their own motion were returned to that pivot by the diurnal motion of the heavens. In other words, the direct motion of the planets moves them in a counterclockwise direction in a circular chart, while the apparent motion of the heavens moves them in a clockwise direction.