Rudolf Steiner: "When at last the whole of the higher man has been developed, the entire astral body will be so completely purified that it will simultaneously become Manas or Spirit-Self; the ether body so thoroughly purged that it will simultaneously become Life-Spirit or Buddhi, and the physical body will be so greatly metamorphosed that it will, at the same time, be as actually a Spirit-Man, Atman, as it is now a physical body. The greatest force will be needed to conquer this lowest body, hence the conquest and transformation of the physical means the greatest victory for the human being. When mankind has fully perfected the physical body, this physical man will then become Spirit-Man or Atman. All this is at present only in germ within the human being, but a time will come when it will live in him in its fullness. And by lifting his gaze to the Christ Personality, to the Christ Impulse, by energizing and strengthening himself through this Christ Impulse, he draws into himself the force that can accomplish this transformation."