Albert Einstein and Leopold Infeld, “The Evolution of Physics,” Touchstone, 1966.

“Science is not and will never be a closed book. Every important advance brings new questions. Every development reveals, in the long run, new and deeper difficulties.” (p. 292)

“Without the belief that it is possible to grasp the reality with our theoretical constructions, without the belief in the inner harmony of our world, there could be no science.” (p. 296)