Because mentalism is to become a vivid fact for him and not remain a mere theory, the advanced disciple will have to convert his joys and agonies into real-seeming dream-stuff. And he will have to achieve this conversion by the power of his own hard will and his own keen understanding. The higher self may help him do this, for he may find that some of the deepest sorrows which befall him are of a special kind. They may be extremely subtle or strikingly paradoxical or tremendous in vicissitudes. For instance, he may be estranged in the most poignant way from those dearest to him, from the master he reveres, the friends he needs, the woman he loves. He may be permitted to meet them in the flesh only briefly and only rarely, so that he will seek compensation by learning the art of meeting them often and long in thought. If these inner experiences can utterly absorb his imaginative attention, they will come to seem as actual as outer ones. If the capacity to introspect be united with the capacity to visualize in this intense way, the result will be astonishingly effectual. Thus he comes in time to see the Mental as Real. Thus he lifts himself from a lower point of view to a higher one. Thus he thoroughly overcomes the extroverted materialism of ordinary human perception.
-- Notebooks Category 21: Mentalism > Chapter 5: The Key To the Spiritual World > # 17
-- Perspectives > Chapter 21: Mentalism > # 62