The Physical Testifies to the Metaphysical

these processes can produce their effects at levels we cannot usually hope to measure directly. It is as if we had a theory of electromagnetism but no means of measuring electric current or magnetic force.” 7. How is the nervous system built? Francis Crick, Salk Institute, California. “Perhaps the most challenging problem in developmental biology is constructing an animal’s nervous system. Many years ago, it was shown by Roger Sperry that if a newt’s eye were removed so that the optic nerve from its eye to its brain was broken, then even if the eye were replaced upside down, the optic nerve would regenerate from the retina, grow towards the brain and connect up again. After a period, the animal could see again with this eye, but it always saw upside down. In other words, the new connection had been made ‘correctly’ except that the eye did not know it had been inverted. The results show that fairly precise processes are at work to make the correct, rather intricate, connections needed between one set of nerves and another, but exactly what these mechanisms are, we do not yet know.” [In other words, the fact that it was upside down shows how specific the links are.] 8. Does the quantum theory apply to gravity? Sir Herman Bondi, Chief Scientist, Department of Energy. “If we follow Einstein’s widely accepted theory of gravity, then any rapid change in the source of a gravitational field—two stars revolve in orbit around each other, for example—should radiate gravitational waves at the speed of light. All other forms of recitation are ‘quantized,’ that is, they are not continuous but come in discrete but minute