Environmentalist Quotes and aphorisms about years John Muir ,, During my first years in the Sierra, I was ever calling on everybody within reach to admire them, b... Paul Hawken Paul Hawken Paul Hawken Paul Hawken ,, Class of 2009: you are going to have to figure out what it means to be a human being on Earth at a ... David R. Brower David R. Brower Paul Watson Richard Leakey Richard Leakey