Bhagvan Mahavira gave as aphorism about such perception. It is a whole chain. A person 'sees' things with anger, sees only his pride. He, who 'sees' his anger, 'sees' the web of maya he has created himself. He, who 'sees' like web of maya, 'sees' his greed. He, who 'sees' his greed, 'sees' what is dear to him. He 'sees' his affection. He, who 'sees' his love, 'sees' his attachment. He, who 'sees' his attachment, 'sees' his malevolence. It is a whole series from anger to birth and death. It has been said, 'see' your anger, 'see' every instinct. If you 'see' instinct, it would become weak. It would grow stronger if you do not 'see' it. When the thief finds the owner of the house awake, he would not enter the house. If the owner is found sleeping, it would facilitate the thief's entry into the house. Let us learn to 'see' what is happening where. This art of 'seeing' establishes the balance of the prana. Imbalance of the prana is the main cause of the diseases. The diseases would he cured when the balance of the prana is restored. 'Seeing', observing is one way of establishing the balance of the prana. Thereby, good chemicals are produced in the body and our power of concentration is enhanced. All these together keep us in the pink of health.
Good sleep, good appetite, mental well-being, good thinking and good feelings are the characteristics of health which are manifest. A person who has all these characteristics is healthy. He who does not sleep well, does not have good appetite, does not have good thoughts and feelings is a sick man.