Most astrologers determine the quality of an aspect depending on the nature of the planets and signs involved and while this is good, it is not always enough
and can to some extent be misleading.
Most know, for example, that a positive aspect between Mars and Jupiter is great, but few realize that a positive aspect between Mars and Saturn can be awful. The positive aspects here try to mesh together two incompatible forces that are best left distanced -which the negative aspects do successfully. We are here speaking of sign aspects(see diagram), with the conjunction, sextile, trine, and opposition(odd or masculine aspects) as generally favourable, and the semi-sextile, square, and inconjunct(even or feminine aspects) as generally unfavorable. Degree aspects intensify what is already there by sign or element.
So if not all positive aspects are good and not all negative aspects are bad how do we distinguish? The answer to this dilemma is solved by the ideal, natural, or home sign chart which looks as follows...
No one I know has this chart(or if it's even possible) but it represents the ideal or "perfect" chart in astrology, where every planet is in its home or ruling sign. Mercury, and to some degree Venus are still in question as regards to which signs they truly rule, but the others are fairly well established.
The way it works is the following...
What is the best or most natural aspect to have, for example, between the Sun and Mars? In the natural chart, Sun, ruler of Leo, is in trine to Mars, ruler of Aries, so the natural aspect to have between the Sun and Mars in any chart(or between charts) is the trine. The natural aspect to have between Uranus and Pluto is the square, and so on. I have taken the liberty to ascribe Earth/Ascendant to Libra which gives some interesting results(discussed later).
Note: the aspects in the diagram begin with Mars/Aries(conjunction or 0°), but they can begin anywhere else on the wheel -it's just to give you an idea of how the aspects follow or are spaced. One space away from the conjunction on either side is the semi-sextile(30°), two spaces away is the sextile(60°), three spaces away is the square(90°), four spaces away is the trine(120°), five spaces away is the quincunx or inconjunct(150°), and six spaces away or directly opposite is the opposition(180°).
So what is the best or most natural aspect to have between Sun and Ascendant(Earth), for example? If we look at the ideal or natural chart the Sun and Earth/Ascendant are in sextile relationship(60°) or two signs apart, such as between Leo and Libra. As most of my readers know, Sun/Ascendant aspects(by sign) define the general tone or harmony of the relationship with the other planetary aspects adding or subtracting from it. They also know that the sextile aspect(represented by Gemini and Aquarius and the 3rd and the 11th houses) is one of communication and freedom -two vital prerequisites for the success of any relationship. Unlike the square(too tense) or the opposition(too open), the sextile allows for just enough compatibility without getting too serious about the relationship. This can be dull or exciting depending on the rest of the aspects, but it is perfect for maintaining overall harmony.
Another thing about the aspects is that most of them are dual so that there are actually 12 instead of 7. The conjunction and opposition have always been singular, like the Sun and Moon rulerships, but the other 5 are not. There are two semi-sextiles, two sextiles, two squares, two, trines, and two inconjuncts -and they are differentiated by being upper or lower, dexter or sinister, or trailing or following. They can even be named after the signs, planets, or houses themselves. I prefer to differentiate the square, for example, as a fourth or tenth house aspect, which are obviously not the same thing. The houses, by the way, are nothing more than an elaborate scheme of describing the specific aspects of planets(by sign) to the Earth/Ascendant. Although I have not fully fathomed its nature or purpose, I treat the MC as a planet.
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