One method of teaching which the ancient rishees adopted was to lead the seeker gradually by way of well-defined, separate stages of enquiry. Thus the reality might first be taken to exist in Matter itself. When the disciple began to have doubts and ask questions later on, as he found this explanation insufficient, he was told that a higher reality existed and it was Life -Principle. In the course of time the limitations of this teaching were discovered by the student and the definition of nonduality was made clear to him. This is precisely the method which I have adopted in my books.
-- Notebooks Category 12: Reflections > Chapter 5: The Literary Work > # 18