On the science of global climate change, I'm an agnostic. I've seen Al Gore's movie, and I've read reports from the Intergovernmental Panel on Climate Change. I've also listened to the 'skeptics. ' I don't know who's right.
A witness, in the sense that I am using the word, is a man whose life and faith are so completely one that when the challenge comes to step out and testify for his faith, he does so, disregarding all risks, accepting all consequences.