Letting things slide is always the easiest thing to do, in parenting no less than in banking, public education, and environmental protection. A lack of discipline is apparent these days in just about every aspect of American society. Why? This should be is a much larger question, one to ponder as we take out the garbage and tie our kids' shoes.

There are a lot of things that we could do to minimize what we're doing, but we're not getting back those frogs that I saw that no longer exist.

Though it might be nice to imagine there once was a time when man lived in harmony with nature, it’s not clear that he ever really did.

Some of these species that are now no longer with us were killed off by a fungal disease that was moved around the planet by people.

It is estimated that one-third of all reef-building corals, a third of all fresh-water mollusks, a third of sharks and rays, a quarter of all mammals, a fifth of all reptiles, and a sixth of all birds are headed toward oblivion. The losses are occurring all over: in the South Pacific and in the North Atlantic, in the Arctic and the Sahel, in lakes and on islands, on mountaintops and in valleys.

Most of the world's major waterways have been diverted or dammed or otherwise manipulated - in the United States, only two per cent of rivers run unimpeded - and people now use half the world's readily accessible freshwater runoff.

I don't think there are too many places left that humans haven't pretty thoroughly explored.