These lectures were not public ones, but were given to members of the
Theosophical Society founded by H. P. Blavatsky; who were accustomed
to specific terms to designate planetary evolution, the members of the
human being, and so on. In his written works, Rudolf Steiner used
terms of which in 1903 he said that for certain reasons I make
use of an occult language that differs somewhat from the expressions
used in published Theosophical writings, but which are of course in
full harmony with them in meaning.
The terms which were exclusively used later by Rudolf Steiner, terms
to which the present-day reader is accustomed, will be found in the
notes at the end of each lecture.