When nature's phenomena are elucidated, pay attention to all its phases.
Nothing is inside, nor outside, because what is inside is also manifested outside.
The skin is the largest organ system of the body. It is a protective barrier between the individual and the external environment. It impedes the penetration of microorganisms, absorbs and blocks radiation, and inhibits the loss of water. It contains several types of sensory receptors, is involved in temperature regulation, and functions in immunologic surveillance. It cannot be covered easily or disguised.