By constraint on the navel chakra—knowledge of the organization of the body.
The navel chakra is the location point of the solar plexus at a subtle and energetic level.
Just as with the analogy of our solar system where the planets are organized around the sun, likewise the ‘organization’ of the body can be known by constraining one’s inner attention on the subtle region of the solar plexus. It is interesting to correlate that in Chinese Medicine, this is the area of the Hara where all the body’s organs are energetically replicated and accessible.
In Yoga physiology and occult anatomy, the navel is the root of the 72,000 nadis or subtle energetic pathways that supply the whole body-mind complex with energy. The navel is considered to be the pivot of the sympathetic nervous system and the brain of the parasympathetic nervous system.
The subtle pervades the tangible. The energetic animates the vessel. The cause is mind, the blueprint the astral, the material the manifested.