It is true, that the study of anatomy, or structure of the human body, and of the whole animal economy is pleasing, and useful. . . . But it is no more necessary to mankind at large, to qualify them to administer relief from pain and sickness, than to a cook in preparing food to satisfy hunger and nourish the body. There is one general cause of hunger, and one general supply of food; one general cause of disease, and one general remedy. . . . That medicine, therefore, that will remove obstructions, promote perspiration, and restore digestion, is suited to every patient, whatever form the disease assumes, and is universally applicable.

Source:

Samuel Thomson, New Guide to Health, or Botanic Family Physician, ninth edition (Columbus, Ohio: Jarvis Pike, 1833).

Phrenology.

Another alternative "scientific" theory that worked its way into popular culture was phrenology. Franz Joseph Gall of Vienna first proposed...