As for the question of how astrology works many answers have been proposed.
The two primary explanations are a) C. Jung's synchronization: events on earth happen simultaneously with astronomical events of a like quality. This concept is the modern expression of an old occult idea of resonance between similar as the microcosm is considered as a replica of the macrocosm. b) The more "scientific" approach which searches for, still unknown, energies proceeding from the planets. No serious physical scientist would ascertain that all energy fields and forces in the cosmos are already known.
These a priori statements may be necessary for the evolution of a theory but all sciences can feel comfortably on sole empiric grounds. Even the concept of causality is sometimes regarded as a property of the mind rather than an attribute of the cosmos. People think causally ( A is the cause of B ) as they perceive events successive in time, but this is not necessarily a universal quality.
Carl Jung, after having studied primitive as well as contemporary designs and drawings, western embroideries and eastern mandalas, he came to the conclusion that everything the human mind depicts has one of the following two forms :
1) it is either a direct line ( sometimes stemming from or going parallel to another line )
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2) or a circle, radiating and expanding more or less uniformly from a center
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3) or a combination of both
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The prescribed forms are present even in the cosmological conceptions : from the Aristotelian and Ptolemaic spheres which surround earth and contain the planets to the contemporary theory of parallel universes and the linear arrow of time.
This undeniable fact may be an accurate reflection of the reality but it can simply be a property of human perception. Maybe the so called anthropic principle, which was proposed in astrophysics ( the universe is such because we understand it in such a way ) is the right one. People look for causes but nature itself may be apathetic to them.
Whatever the perspective, the purely descriptive character of astrology remains intact. As soon as a number of laws, which can prefigure events, is gathered the underlying cause is not necessary for the theory to work. All sciences dare anticipations based on empiric evidence, which is not directly deduced from the initial hypothesis. Humans seek reasons because of an unconscious need for security, the unknown is always an origin of concern. But the possibility that our design is defective and our measuring methods incompatible always remains alive. Within this context people are free to act according to their will as " There is no chance, no destiny, no fate; that can circumvent or hinder or control; the firm resolve of a determined soul" (Ella Wilcox).
As for the forecasting, it is to peoples' advantage to presage external influences and be in concordance with the heavenly rhythms.
