"Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world." - Einstein, Albert in 'Evolution of Physics' 1938

"The subject matter of research is no longer nature in itself, but nature subjected to human questioning . . ." - Heisenberg, Werner Karl (1901-1976)

"A picture without a frame is not a picture." - Wheeler, John Archibald