” For the present I must say that you are on the fair road to health, and the chief sources of your malady cut off. One source still remains, and it is the cause of your last relapse. Man (the delicate human machine) is not constituted for overwork, he cannot overwork his powers or faculties with impunity.
If he does so from ambition, love of gain, or other praiseworthy or blameworthy motive, he sets himself in opposition to the order of nature, and his body suffers injury or destruction.
All the more if his body is already in a weakened condition ; what you cannot accomplish in a week you can do in two weeks. If your customers will not wait they cannot fairly expect that you will for their sakes make yourself ill and work yourself to the grave, leaving your wife a widow and your children orphans.
It is not only the greater bodily exertion that injures you, it is even more the attendant strain on the mind, and the overwrought mind in its turn affects the body injuriously. If you do not assume an attitude of cool indifference, adopting the principle of living first for yourself and only secondly for others, then there is small chance of your recovery.