"When on board HMS Beagle, as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relations of the present to the past..."
"In a letter written in January 1958, Olga Owens Huckins told me of her own bitter experience of a small world made lifeless, and so brought my attention sharply back to a problem with which I had..."
"A well-known scientist (some say it was Bertrand Russell) once gave a public lecture on astronomy."
"There are the so-called inert gases in the air we breathe."
"Intelligent life on a planet comes of age when it first works out the reason for its own existence."