Over the long haul of life on this planet it is the ecologists — and not the bookkeepers of business — who are the ultimate accountants.

Speech to the First National Congress on Optimum Population and Environment (June 9, 1970), cited in Noel Hinrichs (ed.) Population, Environment and People (McGraw-Hill, Inc., 1971), p. 144, and in Alec Lewis (ed.) The Quotable Quotations Book (New York: Thomas Y. Crowell, 1980), p. 62