Click on over to google books and read the June 1978 article in Backpacker Magazine titled Elder of the Tribe: Aldo Leopold. A great primer to Leopold and his "land ethic"."What I am trying to make clear", he wrote, "is that if in a city we had six vacant lots available to the youngsters of a certain neighborhood for playing ball, it might be 'development' to build houses on the first, and the second, and the third, and the fourth, and even on the fifth, but when we build houses on the last one, we forget what houses are for. The sixth house would not be development at all, but rather ... stupidity."After reading the article go to your local library, check out A Sand County Almanac and read it twice.