He is 100% certain in his own mind that human fossil fuel activity is accelerating the demise of humanity. He uses the following bases in our discussions: #1 I have a deep background in computer science. He has a deep background in physics. His arguments to me have been from a physics background. I am quickly lost as he grounds the discussion in physics. #2 because of his personal broad agenda and his involvement in this agenda, he cites so much data and depth of data in logical discussion that I am effectively powerless to refute. He wouldn't argue against any of your points above. He would state that we are only accelerating it vastly. And uses the data points and then his understand of physics from #1. At that point, I am basically stuck . I will admit it, I am basically stuck as I don't spend my time in the area and he does. Embarrasing to tell you but I feel intellectually conquered at that point.