Each of these periods of 12,000 years brings a complete change, both externally in the material world, and internally in the intellectual or electric world, and is called one of the Daiva Yugas or Electric Couple. Thus, in a period of 24,000 years, the sun completes the revolution around its dual and finishes one electric cycle consisting of 12,000 years in an ascending arc and 12,000 years in a descending arc.
Development of dharma, the mental virtue, is but gradual and is divided into four different stages in a period of 12,000 years. The time of 1200 years during which the sun passes through a l/20th portion of its orbit is called Kali Yuga. Dharma, the mental virtue, is then in its first stage and is only a quarter developed; the human intellect cannot comprehend anything beyond the gross material of this ever-changing creation, the external world. (S.Y.)
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