"It seems to me absolutely impossible, without such a Help, to keep the Mind easy, and prevent its wearing out the Body, as the Sword does the Scabbard; it is no matter what it is, provided it be but a Hobby-Horse, and an Amusement, and stop the Current Reflexion and intense Thinking, which Persons of weak Nerves are aptest to run into."
— Cheyne, George (1671-1743)
See The English Malady: or, a Treatise of Nervous Diseases of All Kinds, As Spleen, Vapours, Lowness of Spirits, Hypochondriacal, and Hysterical Distempers, &c. In Three Parts. Part I. of the Nature and Cause of Nervous Distempers. Part II. of the Cure of Nervous Distempers. Part III. Variety of Cases That Illustrate and Confirm the Method of Cure. With the Author’s Own Case at Large. (London: Printed for G. Strahan in Cornhill, and J. Leake at Bath, 1733). <Link to ESTC>