But in 1927 Werner Heisenberg pulled out the rug, and our whole understanding of the universe toppled and collapsed. For some reason it has not yet trickled down to the man on the street that some physicists now are a bunch of wild-eyed, raving mystics. For they have perfected their instruments and methods just enough to whisk away the crucial veil, and what stands revealed is the Cheshire cat’s grin.