Important beliefs and practices in astrology

The core beliefs of astrology were prevalent in parts of the ancient world and are epitomized in the Hermetic maxim, "as above, so below". Tycho Brahe used a similar phrase to summarize his studies in astrology: suspiciendo despicio, "by looking up I see downward".

There are several techniques of forecasting in Western astrology. Transits, the most popular, are based on the actual motion of planets moving through a sign or house within the horoscope. Another technique, progressions are based on the movements of the planets after birth, symbolically related to a time period or cycle of life. Most Western astrologers no longer try to forecast actual events, but focus instead on general trends and developments. Skeptics respond that this practice of western astrologers allows them to avoid making verifiable predictions, and gives them the ability to attach significance to arbitrary and unrelated events, in a way that suits their purpose. By comparison, Hindu astrologers make predictions about both trends and events.

In the past, astrologers often relied on close observation of celestial objects and the charting of their movements. Modern astrologers use data provided by astronomers which are transformed to a set of astrological tables called ephemerides,showing the changing zodiacal positions of the heavenly bodies through time.