Within the ranks of these different beings there are all possible gradations in regard to perfection. In the category of the Angels there are at the beginning of the present Earth-evolution, some standing high and others less developed. The former have progressed far beyond the minimum of their Moon-development. Between these and those who had just reached this minimum when the Moon-evolution had come to an end, and the Earth-evolution had begun, there are all possible gradations. Conformably with this gradation of rank, the beings in question entered during the Earth-period upon the leadership of human evolution. Thus the evolution of the Egyptian civilization was effected under the guidance of beings who had become more perfected on the Moon than those who were the leaders of the Graeco-Roman period, and these again were more perfect than those who have the leadership at the present time. In the Egyptian as also in the Greek Period, those who later on assumed the direction, were meanwhile developing, and making themselves ready to guide the civilization of later periods. Since the time of the great Atlantean catastrophe, seven consecutive epochs of civilization have to be differentiated; the first is the ancient Indian epoch, and it is followed by the ancient Persian.[2] The third is the Egypto-Chaldæic, the fourth is the Graeco-Roman, and the fifth is our own, which, since about the twelfth century, has been gradually developing and in which we are still living. And as the separate periods overlap, we see already in our times those early events preparing which will lead over into the sixth post-Atlantean epoch. And a seventh epoch will succeed the sixth in due course. On closer observation we find the following evidence with regard to the guidance of mankind. It was during the third epoch of civilization, the Egypto-Chaldæic, that the Angels (or lower dhyanic beings according to Oriental mysticism) were to some extent independent leaders of humanity. They were not so during the ancient Persian civilization. For then they were subject to a higher direction in a much greater degree than in the Egyptian times, and had to regulate everything in conformity with the impulses of the hierarchies immediately above them. In this way everything was under the immediate guidance of the Angels, but these themselves submitted to the rulership of the Archangels. And in the Indian epoch when post-Atlantean life had reached such a height in spiritual matters as has never been attained since--a natural height under the direction of great human teachers--then the Archangels themselves were subject in a similar sense to the guidance of the Archai or Primal Powers. Thus if we trace the evolution of humanity from the Indian epoch through the ancient Persian and Egypto-Chaldæic civilization, we may say that certain beings of the higher hierarchies withdrew as it were, ever more and more from the direct guidance of humanity.