Both sides in the debate over global warming are known for calling their opposition all kinds of derisive names. Perhaps the worst is “denier” to describe those who allegedly deny that global warming is “real.” The echoes of Holocaust denial are indeed offensive, particularly because the debate over global warming often conflates science with social science. This matters because one could accept that science has established global warming but still reject for social scientific reasons the claim that the policies normally associated with environmentalism are the proper way to address its effects. Does that make one a “denier?” It is that question I hope to answer indirectly below.

To help clarify what’s at stake, I offer a list of questions that are (or should be) at the center of the debate over anthropogenic (human-caused) global warming. I will provide some quick commentary on some to note their importance and then conclude with what I see as the importance of this list.

1. Is the planet getting warmer? 2. If it’s getting warmer, is that warming caused by humans? Obviously this is a big question because if warming is not human-caused, then it’s not clear how much we can do to reduce it. What we might do about the consequences, however, remains an open question.

3. If it’s getting warmer, by what magnitude? If the magnitude is large, then there’s one set of implications. But if it’s small, then, as we’ll see, it might not be worth responding to. This is a good example of a scientific question with large implications for policy.

Matters of Science

All these questions are presumably matters of science. In principle we ought to be able to answer them using the tools of science, even if they are complex issues that involve competing interpretations and methods. Let’s assume the planet is in fact warming and that humans are the reason.

4. What are the costs of global warming? This question is frequently asked and answered. 5. What are the benefits of global warming? This question needs to be asked as well, as global warming might bring currently arctic areas into a more temperate climate that would enable them to become sources of food. Plus, a warmer planet might decrease the demand for fossil fuels for heating homes and businesses in those formerly colder places. 6. Do the benefits outweigh the costs or do the costs outweigh the benefits? This is also not frequently asked. Obviously, if the benefits outweigh the costs, then we shouldn’t be worrying about global warming. Two other points are worth considering. First, the benefits and costs are not questions of scientific fact because how we do the accounting depends on all kinds of value-laden questions. But that doesn’t mean the cost-benefit comparison isn’t important. Second, this question might depend greatly on the answers to the scientific questions above. In other words: All questions of public policy are ones that require both facts and values to answer. One cannot go directly from science to policy without asking the kinds of questions I’ve raised here. 7. If the costs outweigh the benefits, what sorts of policies are appropriate? There are many too many questions here to deal with in detail, but it should be noted that disagreements over what sorts of policies would best deal with the net costs of global warming are, again, matters of both fact and value, or science and social science. 8. What are the costs of the policies designed to reduce the costs of global warming? This question is not asked nearly enough. Even if we design policies on the blackboard that seem to mitigate the effects of global warming, we have to consider, first, whether those policies are even likely to be passed by politicians as we know them, and second, whether the policies might have associated costs that outweigh their benefits with respect to global warming. So if in our attempt to reduce the effects of global warming we slow economic growth so far as to impoverish more people, or we give powers to governments that are likely to be used in ways having little to do with global warming, we have to consider those results in the total costs and benefits of using policy to combat global warming. This is a question of social science that is no less important than the scientific questions I began with.

I could add more, but this is sufficient to make my key points. First, it is perfectly possible to accept the science of global warming but reject the policies most often put forward to combat it. One can think humans are causing the planet to warm but logically and humanely conclude that we should do nothing about it.

Second, people who take that position and back it up with good arguments should not be called “deniers.” They are not denying the science; they are questioning its implications. In fact, those who think they can go directly from science to policy are, as it turns out, engaged in denial – denial of the relevance of social science.