Einstein wrote in 1931: "The most beautiful experience we can have is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science."
What Lightman means by "the mysterious" is not something New Agey or supernatural, but rather "a sense that we can stand right at the edge between known and unknown and gaze into that cavern and be exhilarated rather than frightened." What thrills Lightman is that in some deeply mysterious way, the human mind can bring some part of the unknown into the light of knowing.
Science is a powerful tool for generating reliable knowledge of the world. Art makes us aware of the abiding mystery. "Just as the world needs both certainty and uncertainty, the world needs questions with answers and questions without answers," Lightman writes.
It's reviewed also in the New York Times:
Like Oliver Sacks, Stephen Jay Gould, Richard Dawkins and countless others, Lightman is that phenomenon mistakenly believed to be rare: a scientist in love with words, one who can write clearly and appealingly about his subject for a lay readership. Science happens to be excellent training for literature; it calls for both narrative ability and a grasp of style, and it sometimes seems as though the ''arts-science divide'' simply reflects the humanities' refusal to believe that anything that originates in a lab could possibly be attractive.