There are hidden contradictions in the minds of people who "love Nature" while deploring the "artificialities" with which "Man has spoiled 'Nature.'" The obvious contradiction lies in their choice of words, which imply that Man and his artifacts are not part of "Nature"–but beavers and their dams are.
...In declaring his love for a beaver dam (erected by beavers for beavers' purposes) and his hatred for dams erected by men (for the purposes of men) the "Naturist" reveals his hatred for his own race–i.e., his own self-hatred.