"Consider a spherical brain," said Kadar. He had plucked a single green grape from a bunch of them on the fruit plate. He now extracted a steak knife from the silverware drawer and used it to cut most, but not all, of the way through the grape. Laks drifted over to watch. Kadar opened the grape like a book. The uncut skin in the back held the two halves of it together like a hinge. "To most people, a piece of fruit not quite cut in half. To a radio engineer, a butterfly antenna."