Leo Tolstoy,
War and Peace
(1869)
“ This simple thought could not occur to the doctors (as it cannot occur to a wizard that he is unable to work his charms) because the business of their lives was to cure, and they received money for it and had spent the best years of their lives on that business. But, above all, that thought was kept out of their minds by the fact that they saw they were really useful, as in fact they were to the whole Rostóv family. Their usefulness did not depend on making the patient swallow substances for the most part harmful (the harm was scarcely perceptible, as they were given in small doses) ”
