Herong's Notes on Astrology and Horoscope - Version 2.11, by Dr. Herong Yang
What Is Astrology
This section describes what is astrology.
The best definition of astrology that I can find on the Internet is from wikipedia.org, where astrology is defined as: Astrology is a group of systems, traditions, and beliefs in which knowledge of the relative positions of celestial bodies and related details is held to be useful in understanding, interpreting, and organizing information about personality, human affairs, and other terrestrial matters.
The word astrology is derived from the Greek word "aster" (star) and "logos" (speech, statement, reason).
Wikipedia's definition of astrology matches well with a portrait included in "Detail of Ptolemy on the Frontispiece of Cellarius Celestial Atlas, 1660", http://www.er.uqam.ca/nobel/r14310/Ptolemy/:
To understand astrology, you need to understand the following:
Astrology has a long history. Astrology started among the ancient Babylonians before 17th century BC, and spread to Greece about the middle of the 4th century BC. Some other cultures and civilizations developed their own branches astrology, like India, China, Maya, etc.
Today, there are three major branches of astrology: Western astrology, Jyotisha (Indian) Astrology, and Chinese astrology. But Western and Indian astrology are essentially similar in many areas.
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