The energies of the twelve constellations are blended with those of the twelve planets, but their power to evoke response, and to be consciously received, recognized and employed, is dependent entirely upon the type of response mechanism of the planetary Life and of the individual man. It has been rightly said that consciousness is dependent upon the vehicles of consciousness, upon their point of development and upon the ability of the individual to identify himself with the energies and impulses which are reaching him, and is not dependent only upon that which is already a recognized part or aspect of himself. It might be said that the higher response to the realities and qualities revealed and made possible by the impact of energy from the zodiacal signs is somewhat dependent upon the waning influence of the planets to hold down the consciousness aspect of the man. Ponder upon this, for it embodies a deep esoteric truth.
Thus, two potent streams of energy – cosmic and systemic – reach man via the conditioning planetary centers of force (the seven planetary schemes in the solar system and their corresponding seven centers in the planet on which we live) and pour into the symbolic “twelve houses” through their medium. It is for this reason that our solar system is spoken of as one of “intrinsic duality” (love-wisdom) and that the major task of man is the “regulation of the pairs of opposites.” The theme of duality, therefore, runs through the whole story of man’s development. Upon all the three planes (physical, astral and mental) of human unfoldment the reconciliation goes forward.
Alice Bailey, Esoteric Astrology, p. 34