There is general agreement amongst astrologers about the signs and what they signify. Houses are much more controversial. There are many different ways to define the location of the house cusps, and so to determine in which house a planet is located.
Throughout his troubled life, Kepler sought a Pythagorean unity between Astronomy and Astrology. He invented three new astrological aspects, along with his three laws of planetary motion. These were part of his quest for the Harmonices Mundi, his magnum opus.
Sacred Geometry is an ancient science with links to religious, philosophical and spiritual beliefs as well as to classical geometry and appears throughout all cultures in human history.
Neil Michelsen was an American computer programmer, astrologer and publisher. He pioneered the calculation and printing of horoscopes at reasonable prices.
Astrologer Paul Westran has a tested theory about relationships. His eight-year study of 1,300 couples examining the correlations between planetary alignments and real events produced some surprising results.
Dennis Elwell was a towering figure in terms of late twentieth century astrology. His legacy includes his book Cosmic Loom: broad and deep in its scope, encompassing tidbits of knowledge from a wide variety of sources, some from the realms of science and philosophy.