Anonymous posted a comment, arguing that
"climate denial is just like climate alarmism, they are both about money and politics. "I would point him towards this infographic and post on the Caudal Lure blog.
"Occam’s razor suggests that the more likely explanation for some phenomenon is the explanation which requires the fewest number of assumptions or required assertions. Even though in science the correct answer is sometimes the more complex one, rationally speaking, the fewer amount of assumptions that we have to make in order to get a theory to work, the better."