"When the photographer Philippe Halsman said, 'Jump,' no one asked how high. People simply pushed off or leapt up to the extent that physical ability and personal decorum allowed. In that airborne instant Mr. Halsman clicked the shutter. He called his method jumpology. The idea of having people jump for the camera can seem like a gimmick, but it is telling that jumpology shares a few syllables with psychology. As Halsman, who died in 1979, said, 'When you ask a person to jump, his attention is mostly directed toward the act of jumping, and the mask falls, so that the real person appears.'"