It appears to be a law that you cannot have a deep sympathy with both man and nature. – Henry David Thoreau, Walden, 1854

To waste, to destroy our natural resources, to skin and exhaust the land instead of using it so as to increase its usefulness, will result in undermining in the days of our children the very prosperity which we ought by right to hand down to them amplified and developed. – Theodore Roosevelt, seventh annual message, 3 December 1907

The control man has secured over nature has far outrun his control over himself. – Ernest Jones, The Life and Work of Sigmund Freud, 1953