Rudolf Steiner presented the lectures printed in this volume to an
audience familiar with Anthroposophy. The reader who wishes fully to
appreciate this volume and who has no prior acquaintance with
Anthroposophy can gain the requisite background by reading
An Outline of Occult Science or
Theosophy.
These are Steiner's
own introductions. Both books are published by the Anthroposophic
Press.