“When you’re able to distinguish the art of the horizon at the bottom of a frame, or at the top of the frame—but not going right through the center of the frame—when you’re able to appreciate why it’s at the top and why it’s at the bottom, you might make a pretty good picture-maker.”
John Ford’s advice to 15-year-old Steven Spielberg
A book I recommend on this subject is The Visual Story by Bruce Block.
P.S. I think that 15-year-old kid figured it out and turned into a pretty good picture-maker.
Screenwriting from Iowa 
[…] “When you’re able to distinguish the art of the horizon at the bottom of a frame, or at the top of the frame—but not going right through the center of the frame—when you’re able to appreciate why it’s at the top and why it’s at the bottom, you might make a pretty good picture-maker.” John […] Original Source… […]