Rudolf Steiner, Berlin, March 21, 1912:
It is not only by looking at the matter in this light that we can furnish evidence for it. We can obtain satisfying evidence — though not a mathematical proof — by turning to nature. In the growth of a plant we see how leaf after leaf develops until the blossoms unfold: how these blossoms are fructified, and seed develops from the fruit. Then the plant withers away. But does its force then come to an end? No, on the contrary: at this very time the forces which call the whole plant back to a new cycle of life are at their strongest. They are now inwardly concentrated at one point, as it were, and they appear again in a new form when the seed is sown in the earth. We then watch the whole plant being renewed; the beginning and the end of its life are thus united.
In like manner the highly concentrated forces in ourselves when we pass through death are united with those seen at the outset of life on Earth. We see how the human being as an infant sleeps through a sort of twilight condition into life. This condition gives free play for work on the body, and this is carried out in such a way that the bodily organs harmonize with the life of the soul. It would be a sad pity if anyone wanted to maintain that the ego is not active until self-consciousness begins. No, its activity begins long before that, and afterwards the human being has only to turn its forces to the building up of consciousness and memory. Before this the forces of the ego are already working on molding the bodily organs so that the still soft and pliable body shall be skillfully made ready to harbor the coming consciousness. Hence we see how the ego is engaged in its greatest work of art at the outset of a person's life, and this shows that he is already in possession of active forces when his memory begins to develop. if we observe the human being quite impartially, we see how he comes to relate himself to the world in his own individual way, and how his undefined features and faculties gradually take form. Finally we see how the force which had previously passed through the gate of death in a concentrated form, in readiness for building up a new body, is now actually at work on it, so that the human being can enter his new body bearing with him the fruits of his former life. In this way the ego proceeds from one earthly life to the next. By actively enhancing the life of a soul, it proves to be endowed with those potent forces which — after continuing to increase until death — maintain their activity during the time between death and rebirth in such a way that the ego can imprint them on another earthly incarnation.
Thus we arrive at the comforting fact — though narrow-minded people will certainly not be in sympathy with it — that many ideals lie ahead still for mankind, besides those derived from ordinary consciousness; and these others include a striving for the power to recall past earthly lives. But I repeat that this is not a matter on which philistine souls can be in accord with Spiritual Science. Only recently I was reading a statement by a man held in great esteem today, in which he advanced the opinion that it would never be possible for human reason to solve all the riddles of the universe — nor would this be desirable, for if all the riddles were solved there would be nothing left for us to do on Earth. Evidently he cannot conceive of evolution progressing beyond its present stage, bringing men new faculties for new tasks, nor can he imagine that what is for people's ‘good’ changes with the enhancement of their consciousness.
Eternity is not bound up with the soul and spirit of man's essential being as a merely fortuitous characteristic, but is a necessity for the nature of the human soul. Neither is Eternity a fortuitous characteristic of the spirit.Eternity belongs to the spirit, is in the spirit, comes forth from the spirit.Eternity lives through the spirit.