Now man, in the form in which he is at present evolving, makes his first appearance upon the fourth of the planetary incarnations which have been described, the Earth proper. And the essential characteristic of his form is that it is composed of four principles, the physical, etheric, and astral bodies and the ego. But that form could not have appeared if it had not been prepared by the preceding events of evolution. The method of preparation was that, in the earlier planetary incarnation, beings were evolved who already had three of the present four principles of man: the physical, etheric, and astral bodies. These beings who, in a certain sense, may be called man’s ancestors, had as yet no ego, but they developed the three other principles and their mutual relationship to such a point that they became sufficiently mature to receive an ego. Thus man’s ancestor attained to a certain degree of maturity of his three principles during the earlier planetary incarnation. This condition became spiritualized; and out of it a new planetary condition was formed in which man’s matured ancestors were contained, as it were, in embryo. Because the whole planet had passed through a process of spiritualization and had appeared in a new form, it offered those embryos, with their physical, etheric, and astral bodies, which were contained therein, not only the opportunity of again evolving up to the level on which they had previously stood, but the further possibility, after having arrived at that level, of reaching out beyond themselves through receiving the ego. The evolution of the Earth divides itself, therefore, into two parts. During the first period the Earth itself appears as a reincarnation of the previous planetary state. But that recurring state is a higher one than that of the previous incarnation, in consequence of the intervening period of spiritualization. And the Earth contains within itself the germs of man’s ancestors belonging to the earlier planet. These were first developed up to the level they had previously reached. The attainment of this level marks the end of the first period. But now, owing to its own higher stage of evolution, the Earth is able to carry the germs still higher, that is, to qualify them for receiving the ego. The second period of the Earth’s evolution is that of the development of the ego in the physical, etheric, and astral bodies. In the same way that man had been thus carried a stage farther by the evolution of the Earth, so also had this been the case during the earlier planetary incarnations. For man had in some measure existed as early as the first of these. Light is therefore thrown on the present constitution of man if his evolution is followed back to the far-remote past of the first of the planetary incarnations mentioned above.