A living universe
The first premise of the esoteric view is that everything in the universe is alive. Every being shows a particular range of vibration, particular qualities, and we know it by those qualities. Astronomy measures the colour, temperature and composition of stars; astrology reads these qualities in psychological language, as virtues and vices. A virtue and a vice are often two uses of the same energy: selfish or altruistic.
As above, so below
Our bodies have circulatory systems such as the nervous system, the bloodstream and the etheric body; life is the movement of energy within a system. The same circulation exists in a nation, a planet and the solar system. No life is independent of the lives around it: we are affected by family, nation and organisations, the planet by the solar system, the solar system by the galaxy. This is the first answer to the question of why astrology works.
The rays come first
The soul ray stays the same for many lives and lives in forms born under many different astrological conditions. The rays of the personality and bodies may change according to what the soul needs next. The rays cannot be deduced from astrological indicators, nor astrology from the rays. That is why the rays come first.
The pattern of the moment
Not only people but organisations, cities, countries and planets are "born". Each moment has its own quality, and the birth chart holds the pattern of that moment. That is why the chart works. The more a being is identified with form rather than life, the more accurately the birth chart shows its "fate".
The point of evolution
The second thing we must know before interpreting a chart is the person's point of evolution: is consciousness oriented towards form or towards life? The chart of someone absorbed in matter and that of a disciple struggling to discipline himself cannot be read the same way. This is not a judgement of good and bad but an assessment of whether energy is used inward, for the self, or outward, for the good of the whole. A baby's chart cannot tell us its point of evolution; we must wait for the soul to show who it is as the child grows.
In competent hands astrology is an exact tool for interpreting the timing and quality of events. It is like mathematics: a perfect instrument, but to someone who cannot use it, a heap of numbers and symbols. The weak link is usually not astrology but the astrologer.
Tropical and sidereal zodiacs
A chart shows where the planets "appear" against a backdrop of signs as seen from the place of birth. The relationships between the planets are real, but the backdrop of signs is not the constellations we see in the sky. Because of the wobble of the Earth's axis, the spring point moves backwards through the signs; today it lies in the last degrees of the constellation Pisces. The constellations are also unequal in width; some, like Virgo, cover nearly sixty degrees.
Yet tropical astrology, based on a thought-form, works: experience and expectation match. Conventional astrology is accurate for those focused on form, esoteric astrology for those living "above the diaphragm", from higher centres. According to esoteric astrology the zodiacal signs are invisible channels focusing the archetypes of the constellations; what matters is that these potent thought-forms act as gateways for the rays and planets.
Crosses, elements and houses
Aries, Cancer, Libra and Capricorn begin the seasons; they form the Cardinal Cross and mark the beginnings of cycles. Taurus, Leo, Scorpio and Aquarius sit in the middle of the seasons; they are the Fixed Cross. Gemini, Virgo, Sagittarius and Pisces are signs of completion and form the Mutable Cross. The signs are also read as triplicities of fire, earth, air and water. The houses are the fields of experience where these energies appear in life. When spring is Aries in the northern hemisphere it is Libra in the southern; the twelve signs can also be seen as six dual signs. Duality is the rule of manifestation.