Here’s a handy way to test the real motivations and intentions you face when debating a climate-change alarmist. Give him this challenge:

Just for the sake of argument, assume that skeptics are right about one thing only — that human-generated carbon dioxide is not a significant contributor to the global warming trend of the past century, nor will it be a significant contributor to the future warning trend. Assume that everything else the alarmists claim is true. Assume that the global mean temperature (yeah, I know, just play along here) will rise by several degrees. Assume that land ice will melt, dump into the sea, and push sea levels up. Assume more flooding, more powerful storms, more precip in places that don’t need it and less precip in places that do. Assume that polar bears and bullfrogs will die. Assume kudzu and other weeds will swallow the countryside. And so on.

Even if the warning trend is a natural phenomenon, caused by sunspots or other cycles uncaused by human action, shouldn’t we try to stop it, anyway? Why are we arguing about causation?

Similarly, try another thought experiment on him. What if the recent warming ended next year. Alarmists claim that we are already experiencing deleterious effects from it. Shouldn’t we take steps to reduce the mean temperature? How far down should we try to take it? What is the “right” temperature?

If your sparring partner argues that human beings shouldn’t interfere with a natural process, then he is giving the game away. His goal is not to maximize benefits and minimize costs associated with climate changes. His goal is to change human action for other reasons, and his motivation is essentially religious.