Even if you go through a very brief period of illness, you suddenly understand the true value of health, what it means to be healthy. Without health, none of the other dimensions of our life mean anything to us. Our work, family, wealth, possessions will mean nothing if we have no health. Ill health comes to us in two fundamentally different ways. One is we may acquire infectious diseases that we contract by living in the world. If we have an infection you must go to the doctor because infection is like an invasion from outside. It has to be handled on war footing. Largely we do chemical warfare, but it is fine because it is a war. But over 70% of the ailments that people suffer from are generally self-help in the sense they are chronic ailments created from within. Our own system has begun to work against us.
The word disease means it is dis ease, that means you have lost the ability to keep the system at ease or in other words the system has become frictious. Many dimensions of human mechanism are not able to function in a cohesive manner. There is a certain amount of friction which causes some ailment or the other. No ailment is hereditary by itself. It is just that we may have a certain organ or certain part of the body inherently weak from our parentage and hence we may go through the same ailment if we go through similar lifestyles, but there is ample evidence to show that if we do necessary things consciously with our body, mind, and energies what ailments our parents might have had need not come to us if we are able to handle our lives little more consciously and the process can be easily reversed. This human system in Yoga, we look at it as five sheaths or five layers. Five layers of body. In the Yogic system there is no such thing as mind. There is no such thing as anything. Everything is seen as body.