Astrology

Astrology refers to any of several systems, traditions or beliefs in which knowledge of the apparent positions of celestial bodies is held to be useful in understanding, interpreting, and organizing knowledge about human affairs and events on earth. A practitioner of astrology is called an astrologer or, less often, an astrologist.

 

The word is derived from the Greek αστρολογία = άστρον, astron, "star" and the English suffix, -ology, "study or discipline". -ology is in turn derived from the Greek λόγος, logos, which has a variety of meanings in English but generally related to "systematic thought or speech".

Although the two fields share a common origin, modern astronomy as practiced is not to be confused with astrology. While astronomy is the study and observation of celestial objects and their movements through space, astrology is the study of the supposed correlation of those objects with earthly affairs. There is as yet no evidence that astrology has a falsifiable, scientific basis.
Description
The core principles of astrology reflect a general principle, which was accepted throughout most of the ancient world, that events in the heavens could have analogies on Earth. Such ancient beliefs are epitomized in the Hermetic maxim: As Above, So Below. The famous astronomer/astrologer Tycho Brahe also used a similar phrase to justify his studies in astrology: Suspiciendo despicio — "By looking up I see downward." Although the principle that events in the heavens are mirrored by those on Earth was one generally held in most traditions of astrology across the world, historically in the West there has been a debate among astrologers over the nature of the mechanism behind astrology and whether or not celestial bodies are only signs or portents of events, or if they are actual causes of events through some sort of force or mechanism.

Many of those who practice astrology believe the positions of certain celestial bodies either influence or correlate with people's personality traits, important events in their lives, physical characteristics, and to some extent their destiny.

All astrological traditions are based on the relative positions and movements of various real and construed celestial bodies as seen at the time and place of the event being studied. These are chiefly the Sun, Moon, planets, and the lunar nodes. The calculations performed in astrology may involve arithmetic and simple geometry and serve to locate the apparent position of heavenly bodies on desired dates and times based on astronomical tables.

In past centuries astrology often relied on close observation of celestial objects, and the charting of their movements, and might be considered a protoscience in this regard. In modern times astrologers have tended to rely on data drawn up by astronomers and set out in a set of tables called an ephemeris, which shows the changing positions of the heavenly bodies through time. It is the interpretation of these science-based tables that makes astrology a target for the label pseudoscience.