When a man has practised this exercise for some time and to some competency, he will become repeatedly aware of a curious experience. For a few minutes at most and often only for a few moments, he will seem to have stepped outside his body and to be confronting himself, looking at his own face as though it were someone else's. Or he will seem to be standing behind his own body and seeing his face from a side angle. This is an important and significant experience.
-- Notebooks Category 23: Advanced Contemplation > Chapter 6: Advanced Meditation > # 91