What is health? It is a state of equilibrium of the three humours of the body, viz., Vata, Pitta and Kapha (wind, bile and phlegm), wherein the mind and all the organs of the body work in harmony and concord, and the man enjoys peace and happiness, and performs his duties of life with comfort and ease. It is that condition in which man has a good digestion and a good appetite, normal breathing and pulse, a good quantity and quality of blood, strong nerves and a calm mind, a sound mind in a sound body, a free movement of bowels, normal state of urine, rosy cheeks, shining face and sparkling eyes. It is that state in which a man jumps, sings, smiles, laughs, whistles and moves about hither and thither with joy and ecstasy. It is that condition in which he can think properly, speak properly and act with alacrity, nimbleness and vigilance.
This desirable state is coveted by all. A life with good health is a great blessing indeed. What is the earthly use of wealth and possession, if a man cannot eat well on account of disease of his stomach, if he cannot walk on account of rheumatism or paralysis, if he cannot see the beautiful scenery, of nature on account of cataract or any defective vision, if he cannot copulate on account of impotency. A great thinker says: "Give me health and a day: I will make the pomp of emperors ridiculous." Life without good health is a miserable condition, even if one is the Lord of the whole earth.
Man enjoys good health on account of good Karmas done in his previous birth. He who has done meritorious services in his previous incarnation, he who has shared what he had with others, he who has helped the poor and the needy, he who has done worship, meditation, Yogic Kriyas and Pranayama in his previous birth, enjoys sound health in this birth. The law of causation is inexorable and unrelenting.
What is the greatest thing that a man can achieve in this world? It is Self-realisation. What are the advantages or benefits of Self-realisation? Why should we attempt Self-realisation at all? The attainment of Atma Jnana or realisation of the identity of the Jiva (individual soul) and Brahman (supreme soul) can alone put an end to the wheel of birth and death with its concomitant evils of disease, old age, pain, suffering, worries and various other sorts of trouble. It is Atma Jnana alone that can give you unalloyed eternal bliss, supreme peace, highest knowledge and immortality.
The next question is, why should we have good health? We should have good health in order that we may achieve the four kinds of Purushartha-Dharma, Artha, Kama and Moksha (righteousness, wealth, desires and liberation). If you do virtuous deeds, you will get wealth and you can gratify your worldly desires. Then you can attempt realisation of the Self. Without good health you cannot achieve anything.
Without good health you cannot perform any service of Nishkamya Karma Yoga. Without good health you cannot do Asanas and Pranayama. That is the reason why scriptures declare that this body is a boat to cross the ocean of Samsara, an instrument for doing virtuous deeds and attaining Moksha. That is the reason why, in Charaka Samhita you will find: Dharmartha Kamamokshanam Arogyam moolam uttamam—health is the best thing in this world.
An aspirant should be free from Adhi and Vyadhi (diseases of the mind and the body), if he wants to do Karma Yoga and attain knowledge of the Self. According to the science of Yoga all physical diseases take their origin in the diseases of the mind, from an unhealthy state of mind. The Western psychologists also corroborate this fact. They say that the diseases of the body are attributable to hatred, anger, worry, depression, etc., which corrode the mind and react on the body and bring about various physical diseases by destroying the cells of the body.
A student of Karma Yoga should have an elementary knowledge of Raja Yoga, psychology, Ayurveda, physiology, family medicine, hygiene, Sankhya and Vedanta. Then he will be able to turn out more real work easily. He can have a knowledge of the laws of the mind, also the nature, habits and ways of the mind. He will be in a position to keep a calm and healthy mind always. No one can work smoothly with a ruffled mind. A ruffled mind disturbs the three humours of the body and brings diseases in its turn. This is the theory of Ayurveda which quite tallies with the theory of Raja Yoga and the theory of Western psychologists. He can have an understanding of the laws of the universe and the operation of the world by having a knowledge of the Sankhya philosophy of Kapila Muni. An elementary knowledge of astrology is of immense value. The various Ritus or seasons are brought about by the movement of the earth round the sun. The atmospheric conditions affect the body of man. The planets have an influence on the mind and body of a man. They exercise benign or malevolent influence on him in accordance with their position in the various houses. He who has some knowledge of astrology can ward off the evil effects of unfavourable planets.
At every second various kinds of vibrations from the various kinds of objects of the physical universe outside enter the mind of a man and produce various influences. The body is part of the universe. So is the mind. What is called world is only mind. The mind of a man is affected by the thoughts and opinions of others. There is pressure of thought from outside. All people entertain personal thoughts and the Karma Yogi should have immense strength to act against these outside thoughts. He should have courage. He should have patience and perseverance. Even if he fails twenty times he should stick to his work with determination and leech-like tenacity, adamantine will and asinine patience. Then only will he have perfect success in the end. He will come out of the field with spiritual laurels, Atmic victory and Atmic Svarajya.
Study of Sankhya philosophy will give you a knowledge of the creation of the universe, how the mind is formed, how the organs of action and sensation are formed, what are Tanmatras or rudimentary root elements, what is Mahat-tattva, what is Purusha and Prakriti, what are the three Gunas, how they operate and influence a man, how they affect the health and mentality of a man and how to get knowledge of the Purusha. Sankhya and Yoga of Patanjali are complimentary. Vedanta is only an amplification and fulfilment of Sankhya.
Good physical health can be achieved and also maintained by observing rigidly the laws of health and the rules of hygiene, by taking wholesome, light, substantial, easily digestible, nutritious, bland food or Sattvic diet, and by inhaling pure air, by regular exercise, by daily cold bath, by observing moderation in eating, drinking, sexual intercourse, etc. Good mental health can be attained and maintained by Japa, meditation, Brahmacharya, practice of Yama and Niyama and right conduct, right thinking, right speaking and right action, Atma Vichara, change of thought, relaxation of mind by dwelling the mind on pleasant thoughts, mental recreation and the practice of cheerfulness.
May we all work unselfishly with perfect harmony and healthy co-operation for the well-being of the world and for our own uplift! May our limbs and organs grow strong and healthy! May we live to the normal length of our earthly days-a hundred years-doing selfless service, studying the Vedas and developing all Sattvic virtues! May we shine with the knowledge of Brahman, radiating joy, peace, bliss and knowledge to the different corners of the world!