We must firmly grasp this principle, that the only objects we know, the only world of our experience, have no existence apart from the mind. They do not and cannot subsist externally by themselves. That which projects them into space is mind, and as space itself is within the mind, their independent existence is sheer illusion, or Maya as Indians call it. We must look behind their illusory independence into the mind from which they spring.
-- Notebooks Category 21: Mentalism > Chapter 2: The World As Mental > # 81