The first important need is to separate himself in thought and outlook from the animal side of his nature--not for any moral reasons but for metaphysical ones--and part of the inner work which this calls for is to take up the observer role. He is to look at the body (and its actions, desires, and passions) as if it were apart from himself--in short, to gain a detached view. This practice is fruitful because one idea can be used to counter or displace a second idea: both cannot be held in attention simultaneously. When this has been carried on for a long enough time to show its benefits, it may be used on a higher and more elusive level: he can adopt the impersonal observer attitude towards the ego itself, of which the body is of course a part.
-- Notebooks Category 23: Advanced Contemplation > Chapter 6: Advanced Meditation > # 98