II. Esoteric Development and Super-sensible Knowledge
These organs develop through the exercises that the teacher assigns to the student, in the same way as the sense organs of the physical body develop by practice, for example through the influence of light and sound. You can see one as a physical and the other as a spiritual process of exactly the same duration. You must not believe that any riotous processes, magic, or some such things, could lead someone to develop these sense organs. It is only intimate processes, learning by thinking thoughts that have the strength in them to develop such organs. Hereby it is consistently important that the human being learns what these thoughts are, and that he focuses on a particular bodily organ, for example at a point in his brain located one centimetre below the middle of the eyebrows. If a human being now focuses on this point whilst using a specific combination of words, he will awaken certain abilities inside his astral body. It is all systematically and, one could say, technically determined.
Cite:
GA 98/esoteric_development_and_super-sensible_knowledge/p009 · edition English