Every creature on the planet lives by killing other creatures, and we're not better, but we're also no worse.

Human beings are the only beings that understand "value". A dog doesn't care whether it lives or dies; "caring" is beyond its mental capacity. A dog doesn't care if we destroy the ozone layer or spread garbage around or waste fossil fuels. We are everything good in the world and everything evil; those concepts only apply to people. Without people there would be no good or evil; there might be worth in the world, but there would be no one and nothing to appreciate worth; there might be beauty, but nothing could understand it. The world might as well not exist, if we aren't on it.