Astrology: (from Greek: αστρολογία = άστρον + λόγος) refers to any of several systems of understanding, interpreting and organizing knowledge about reality and human existence, based on the relative positions and movement of various real and construed celestial bodies, chiefly the Sun, Moon, planets, and lunar nodes as seen at the time and place of a birth or other event being studied. For many astrologers the relationship need not be causal.
Common forms of astrology include Western astrology, Chinese astrology, Jyotish (Vedic astrology) and Kabbalistic astrology. All of these can be subdivided by type, such as natal (the study of a person's birth chart), horary (a chart drawn to answer a specific question), and electional astrology (a chart drawn ahead of time to determine the best moment to begin an enterprise or undertaking).
The majority of Western astrologers based their work on the tropical zodiac, but some Western and all Jyotish (Hindu) astologers use the sidereal zodiac.
Relationship to astronomy and science
Astrology is not the same as astronomy. Astronomers are often dismayed at being confused with their counterparts in astrology, and vice versa. Because they regard it as not adhering to standards of the scientific method mainstream Western scientists commonly dismiss astrology to be a pseudoscience.
Astrology was once deeply intertwined with astronomy, and a clear divergence between the two dates back only to the time of Galileo. He was one of the first to use the scientific method to test objective statements about the heavens.
Astronomy aims to understand the physical workings of the universe. These particulars are of great interest and relevance in astrology. The main focus of most forms of astrology are on unproven correlations between the physical motions of heavenly bodies, and various human affairs, such as world events, events in people's personal lives, and inborn personality traits. Other astrologers extend these correlations to geological phenomena unrelated to human activity, such as earthquakes and volcanic eruptions.
Many prominent figures in the early history of western astronomy, including Tycho Brahe, Johannes Kepler, and Galileo himself, also supported themselves by practising astrology for wealthy noblemen. Isaac Newton is sometimes cited as having an interest on astrology, but the proposed evidence does not stand up to close examination. There is not a single word recorded in Newton's hand that mentions the subject, and the handful of books in his possession that contained references to astrology were primarily concerned with other subjects.
There are some biological phenomena that co-ordinate with celestial movements (e.g. circadian rhythms, see Chronobiology). These results do not prove or disprove astrological claims, but suggest influences that are not fully understood. Scientific attempts to prove astrological influence have yielded negative or inconclusive results, for disputed reasons. Scientists would say astrology has no foundation in reality, and therefore cannot be proven. Astrologers would say scientists have designed the studies poorly because of an inadequate understanding of astrology.
Astrological concepts are pervasive in many societies, and endure despite strong efforts by scientists to discredit them. This is evidenced by the fact that influenza was so named because doctors once believed it to be caused by unfavorable planetary and stellar influences.
Astrology as a descriptive language for the mind
Astrology can also be viewed as a cultural system of symbolism for talking about matters of the mind and personality in western culture. It has roots in alchemical and Hermetic tradition which were very influential until the 17th century. Only through an understanding of astrology's system for analysing human behaviour can much western thought and literature up to the Enlightenment be fully understood. Many modern thinkers, notably Carl Jung, have acknowledged its descriptive powers of the mind without necessarily subscribing to its predictive claims.