Astrology was developed along with astronomy almost at the same time by Greeks and Indians. Various clusters of stars seen all around the year were named . The movements of sun and planets were studied in details by using the mathematical methods known at that time.In "SuryaSiddhanta" Brahma the creator is said to have revealed the laws of creation to a disciple . The book gives the mathematical treatment of astronomy in a different angle than that of Greeks. A comparative study of both was done by Rev.E.Burgess a Dutch priest published in 1850. "Brihat Parashara Hora " is the primer on Vedic Astrology and most scholars view Parashara today as the father of mainstream Vedic Astrology. Hora Sastra of Varahamihira is another important book. Kalyana Varma had programmed the astrological knowledge of that times in Volumes Saravalli .B.V.Raman and R. Santanam have popularized these works with their English translations.
When I undertook the task of designing this software I could get help and advice from many scholars who helped me by offering their books for reference. My contacts with real astrologers were many and really wonderful!.
In astrological calligraphy there are only nine planets, two of them nodes and hence only nine letters and 12 signs giving different meanings to them. Even if the astrology contains all objects of Chinese calligraphy as planets ,it can't explain every phenomenon in human life . Astrologer can not be logically cornered ,due to a simple reason, that in prediction every matter on which advice is sought depend on three to five houses, and all the nine planets are related to one or the other of the houses. It depends on astrologers intuition to judge which of them is important.Hence explaining away the past is simple .What is stored for future?. Here comes the challenge, Can a computer help to pick up proper planets ?. By patiently going through the computer analysis of 50 persons (table look up and comparison only).You will see that ancients had wisdom . Planets have their code.!!
How atrologers make judgements?. They use Birth charts and Transit charts at the time of judgement of events. While Ascendant(Lagna) is as important as Moon in birth charts, Moon has the importance in transit charts. Relative placements of other planets about these important positions brings good or bad results. Another important planet is Ruling Dasa Lord of Vimsothari dasa system, of which position triggers the thinking of astrologers. Vedic astrology make use of Dasa systems for timing of events, the most important of which is Vimsothari Dasa .Every planet including Rahu and Ketu are assigned to rule an arbitrary number of years in one's life.There is no direct scientific explantion given in books. Grace Inglis in his book HINDU DASA SYSTEM gives some opinions based on orbital constants of planets .
Critics of astrology boast that physical sciences depend upon a cause and effect relationship, which astrology apparently lacks. They, however, fail to appreciate that astrology is a cosmic science which treats life or awareness of oneself is a flow of cosmic energy starting at birth and ending at death.Hindu philosophy speaks of re-birth also. Neils Bohr proposed structure of hydrogen based on planetary motion.But we know one is not cause of other. Medical diagnosis,laws of economics,weather forcasts ect.are the fields were predictions are diffcult due to multiple causes and Chaos due to their interaction
Physical sciences, which treat Chaos is not well developed. In the case of astrology,if it turns out to yield stastitically better results than the average, the cause may be subtle. The subtle cause in case of astrology is the cosmic force represented by the disposition of the various heavenly bodies or planets.
There are strong differences of opinion among scholars of vedic astrology about value of ayanamsa. Mr. B.V.Raman who was aware of the limitations of astrology proposed an ayanamsa different by more than one degree from Lahiri system which is commonly used. One degree difference would make the times of events delay by more than an year on an average . The reality is that theory of errors in birth-time, latitude, longitude and planetary constants, makes divisions less than Navamsa meaningless. Direct questions and feedback from customers about past events are used by astrologers in predictions .
Vivekananda Says:It is not the sign of a candid and scientific mind to throw overboard anything without proper investigation. Surface scientists, unable to explain the various extraordinary mental phenomena, strive to ignore their very existence.What little I know I will tell you. So far as I can reason it out I will do so, but as to what I do not know I will simply tell you what the books say. It is wrong to believe blindly. You must exercise your own reason and judgment; you must practise, and see whether these things happen or not. Just as you would take up any other science, exactly in the same manner you should take up this science for study.