The fact that I have entitled this book Occult Science has immediately called forth misunderstandings. From many sides was heard, “What claims to be science must not be secret, occult.” How little thought was exercised in making such an objection! As though someone who reveals a subject matter would want to be secretive about it. This entire book shows that it was not the intention to designate anything “occult,” but to bring everything into a form that renders it as understandable as any science. Or do we not wish to say when we employ the term “natural science” that we are dealing with the knowledge of “nature”? Occult science is the science of what occurs occultly insofar as it is not perceived in external nature, but in that region toward which the soul turns when it directs its inner being toward the spirit.
Source: Rudolf Steiner – GA 13 – OCCULT SCIENCE – Preface, Sixteenth to Twentieth Edition
Translated by Maud and Henry B. Monges and revised for this edition by Lisa D. Monges.