Scientists have called him a genius, a prophet, a visionary. He transformed the study of optics and established the principles of celestial workings. His universal laws of gravity gave us an insight into the mysterious forces exerted by the Earth. It was he who, for the first time, explained the nature of tides. He discovered the differential and integral Calculus. A new system of chronology was invented by him. He created a system of the universe of force and inertia and mass, of action and reaction that still remains reliable and efficient. Stephen Hawking and Werner Israel have stated that "Newton's theories will never be outmoded."