If you believe that the world of material things is outside you, that matter is a separate and solid entity, experience will confirm your belief. You will be a materialist, no matter how pious your life. If, however, by profound thought, deep meditation, and other preliminaries, you have removed some of the obstacles which surround and entrap most people, then you may be more likely to let light dawn within you. You may get the shattering experience of the mentalist revelation: many many discoveries will then be made. You will discover that the world is a form taken by consciousness. You will learn the meaning of the void.
-- Notebooks Category 21: Mentalism > Chapter 5: The Key To the Spiritual World > # 128