"A scientist is a man who tries to understand the world by experiment, and a philosopher is a man who tries to understand the world by thought."

"The human mind is a wonderful thing. It starts working the moment you are born and never stops until you stand up to speak in public."

"When we speak of the 'reality' of the external world, we mean that it is independent of our perception of it."

"The old pioneers of science, such as Galileo, Kepler, Newton, were deeply religious men."

"The future of humanity depends on our ability to understand and harness the power of science."