Photography is a marvelous discovery, a science that has attracted the greatest intellects, an art that has excited the most astute minds—and one that can be practiced by any imbecile … Photographic theory can be taught in an hour, the basic technique in a day. But what cannot be taught is a feeling for light … It is how light lies on the face that you as artist must capture. Nor can one be taught how to grasp the personality of the sitter. To produce an intimate likeness rather than a banal portrait, the result of mere chance, you must put yourself at once in communication with the sitter, size up his thoughts and his very character.

Nadar (Gaspard-Félix Tournachon)

Quoted in the biography Nadar by Jean Prinet and Antoinette Dilasser