There is a wisdom in this; beyond the rules of physic: a man”s own observation, what he finds good of, and what he finds hurt of, is the best physic to preserve health. But it is a safer conclusion to say, This agreeth not well with me, therefore, I will not continue it; than this, I find no offence of this, therefore I may use it. For strength of nature in youth, passeth over many excesses, which are owing a man till his age. Discern of the coming on of years, and think not to do the same things still; for age will not be defied.
Beware of sudden change, in any great point of diet, and, if necessity inforce it, fit the rest to it. For it is a secret both in nature and state, that it is safer to change many things, than one. Examine thy customs of diet, sleep, exercise, apparel, and the like; and try, in any thing thou shalt judge hurtful, to discontinue it, by little and little; but so, as if thou dost find any inconvenience by the change, thou come back to it again: for it is hard to distinguish that which is generally held good and wholesome, from that which is good particularly, and fit for thine own body.
To be free-minded and cheerfully disposed, at hours of meat, and of sleep, and of exercise, is one of the best precepts of long lasting. As for the passions, and studies of the mind; avoid envy, anxious fears; anger fretting inwards; subtle and knotty inquisitions; joys and exhilarations in excess; sadness not communicated. Entertain hopes; mirth rather than joy; variety of delights, rather than surfeit of them; wonder and admiration, and therefore novelties; studies that fill the mind with splendid and illustrious objects, as histories, fables, and contemplations of nature.
If you fly physic in health altogether, it will be too strange for your body, when you shall need it. If you make it too familiar, it will work no extraordinary effect, when sickness cometh. I commend rather some diet for certain seasons, than frequent use of physic, except it be grown into a custom. For those diets alter the body more, and trouble it less. Despise no new accident in your body, but ask opinion of it. In sickness, respect health principally; and in health, action.
For those that put their bodies to endure in health, may in most sicknesses, which are not very sharp, be cured only with diet, and tendering. Celsus could never have spoken it as a physician, had he not been a wise man withal, when he giveth it for one of the great precepts of health and lasting, that a man do vary, and interchange contraries, but with an inclination to the more benign extreme: use fasting and full eating, but rather full eating; watching and sleep, but rather sleep; sitting and exercise, but rather exercise; and the like.
So shall nature be cherished, and yet taught masteries. Physicians are, some of them, so pleasing and conformable to the humor of the patient, as they press not the true cure of the disease; and some other are so regular, in proceeding according to art for the disease, as they respect not sufficiently the condition of the patient. Take one of a middle temper; or if it may not be found in one man, combine two of either sort; and forget not to call as well, the best acquainted with your body, as the best reputed of for his faculty.