The inside and the outside of everything is one of the basic conditions of human existence. Its most obvious appearance is that we all have an outside, all that is outside our skin, and we have an inside, which is our body and our mind. Normally we do not pay much attention to the inside of our body, but as soon as we suffer from stomach-ache or headache we notice that this "inside" certainly is something as important and complex as the outside we constantly deal with as long as we are not asleep.