Outside is form,
Inside is thought.
Deepest is the soul.
Traditional sages describe a human being as having three sheaths. The outer one is the physical body and incorporates primitive drives and instincts. The inner one is the mind and includes discrimination, reasoning, and sense of individuality.
Both the body and the mind are enslaved to the outer world because they gain their knowledge from sensory input. They cannot know anything “intangible,” anything without a form or a name.
At the core of every person is the soul. This is a pure, virgin self. It does not think in the ordinary sense of the word, has no egotism, and is not concerned with maintaining itself in the world. Although the body has a shape and the mind is multi-faceted, the soul is completely without form or features. No markings, profiles, names, formulas, numbers, ideas, or conceptions can be projected upon it. It is pure, shapeless, and empty.
Any person with training can reach this soul. Only then can you be convinced of its presence. When you reach it, your body and mind will become irrelevant, for you are now in a state beyond the senses and beyond thought. The soul is called absolute because it is beyond all relativity.