"The quantum of action plays a fundamental role in atomic theory."

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

"The history of science shows that even the most firmly established theories can be overturned by new discoveries."

"The highest task of physics is to arrive at the knowledge of the human mind."

"An experiment is a question which science poses to Nature, and a measurement is the recording of Nature's answer."