London. Early 1950's. The Magnum photographer Ernst Haas is discussing what makes a good photographer with the legendary war photographer, Robert Capa. Haas suddenly turns towards Capa " Do you know the arab oath?" asks Haas. Capa remains silent as Haas explains. "The arabs swear by three things: the eye, the heart, the head - that's all you need to look for in a photographer".
I don't know if the arab oath Haas quoted is real but it certainly makes it much easier to define what makes a good photographer.