Global warming may cause humans and other species to change or disappear but Planet Earth will survive, scientist and environmental activist David Suzuki tells Bill Moyers in the second of their two conversations this week on Moyers & Company (check local listings). We live in a time, Suzuki says, "when human beings have become a geological force. We're altering the physical, chemical and biological features of the planet on a geological scale. "... A lot of my colleagues have now said it's too late... [that] we've passed too many tipping points to go back. My answer is thank you for the message of urgency. We don't know enough to say it's too late... I believe that nature has many more surprises if we can pull back and give her room. And that's the basis of my hope.... I see where all the curves are going, but I still cling to hope as the thing we've got to grab onto if we give nature a chance." Continuing attempts on the part of politicians and big business to censor and attack those who speak the truth about climate change are pervasive, Suzuki notes: "This is a very effective thing that we know has been done by the tobacco industry [and] it's being done by the fossil fuel industry... You attack a person on the basis of their trustworthiness, their ulterior motives, anything to get away from dealing with the issues... That really sends a chill through the scientific community," he continues. "That really scares me because if you can't have scientists telling you what the information is on various issues, who then do we go to for the authority? Do we go to the Bible? Do we go to the Koran? Do we go to these rightwing think tanks? ...That's why it's really important to me that scientists not only be freed but be recognized as the most authoritative source of information on these various issues." David Suzuki is a geneticist, author and broadcaster known to many as "the godfather of the environmental movement." Since 1979, he has hosted the Canadian TV series "The Nature of Things." In a recent poll of his fellow Canadians he was named that country's most admired figure, yet his outspoken views on climate change and government collusion with the petrochemical industry have made him the target of relentless attacks from his nation's prime minister, corporations, and right-wing ideologues.