and this evening i want to welcome bill mckibben. [applause] >> bill is a scholar in residence at middle bury college. and he's cofounder of the online community 350.org. in case you don't know the number -- the name of the organization, 350 comes from the fact that leading scientists have said that only 35 parts per million in the atmosphere is the most that any climate can tolerate. and if it goes over that, things are getting very unsafe. more than 20 years ago, in his book "the end of nature," bill mckibben warned about the impact of the destructive practices that could and have led to global warming. through 12 books in the past 20 years, he's continued his witness to the earth's declining health and its atmosphere's swelling pollution. and now bill mckibben's book, his new book "earth" and he'll speak why it has an ideocratic spelling is a passionate indictment of our wasteful activity along with a practical vision of maintaining what resources we have left. and then you'll find right across the front of the book a wonderful st