Manly Palmer Hall was a genius. Karl Jung borrowed thought and idea from him, and even copied writings from some of his personal papers. Jung and Freud are known as the fathers of psychology, and Jung found it ideal to understand the nature of the human psyche by admitting that there are things beyond our control, and that these things could be read.
Manly Palmer Hall realized early on that astrology needed to separate itself from the Carney background that it had developed. It needed to prove, or at least develop a sound theory that rationalized the ability to predict happenings, feelings, and personalities. Manly Palmer Hall created the philosophy of astrology. He equated astrology to Pythagorean mathematics, giving astrology a fundamental and logical basis from which to work. If astrology could be based in sound mathematic and scientific principles, if astrology could be planted on firm ground, then it could grow to become the science that it is today, the science that utilizes technology and research to define its abilities and capabilities. Manly Palmer Hall as to astrology what Nietzsche, Camus, Sartre, Socrates, and Plato were to philosophy. He thought therefore he was, and he thought therefore astrology is. Manly Palmer Hall was definitely the greatest astrologer of all time. Villenfraiche was huge and Dixon and so forth, but the fact of the matter is, Hall was the one that put astrology on the scientific map. Before Manly Palmer Hall astrology was tarot cards and crazy gypsy readings and wives tales and people that ripped you off.
These days astrology is a respected scientific endeavor that creates complex scientific charts based on the movement of the stars and the suns and the planets and its all possible because of the dedicated work of Manly Palmer Hall.
Manly Palmer Hall was a genius that existed way before his time. He instituted principles of astrology and common thought that are practiced and taught today. His books are still sold in mass quantities and originals and old prints are considered collectors items, but most importantly his principles are applied around the world in most astrological schools of thought. Astrology today is a huge business and generates tons of research that affect many thousands, perhaps millions of lives, and none of this work, and none of the work in the field of astrology for decades to come would be possible were it not for the existence, work, and school of thought of a man like Manly Palmer Hall.