So long as the body is affected through the mind, no audacious device, even of the most manifestly dishonest character, can fail of producing occasional good to those who yield it an implicit or even a partial faith.

Oliver Wendell Holmes, Sr. (1809-1894) American poet, essayist, scholar

Lecture (1842), “Homœopathy and Its Kindred Delusions,” Boston Society for the Diffusion of Useful Knowledge
    (Source)

Collected in Medical Essays, 1842-1882, ch. 1 (1891 ed.).