For this edition I have almost entirely rewritten the opening chapter on the character of Occult Science. I think there will now be less cause for misunderstanding. How often have I heard it said: While other branches of learning offer scientific proofs, this pretended science merely declares that such and such are the findings of Occult Science. It is a natural objection. The proof of supersensible knowledge can never be as tangible and compelling as with things seen and experienced by the outer senses. It is a misconception none the less, and in the altered version I have tried to bring this out more clearly than I appear to have succeeded in doing in the earlier editions.
For the rest, I have introduced changes and additions, trying to make the explanations clearer and more cogent. In many parts of the book, the oft-repeated experience of the spiritual realities described convinced me of the need to modify the forms of expression in which I try to clothe them, and I have done my best to make the necessary changes.
Berlin, May 1920