Yesterday in my seminar on the philosophy of religion we had a discussion about burden of proof. Burden questions seem to be a tricky mix of psychology, politics, and epistemology–to name a few things. And this goes back to the second feature of critical thinking–at least the second one we came up with here (yesterday)–i.e., know where you stand. This doesn’t mean of course that you should know and defend where you stand, and be aware of the status of the questions before you (the first step–maybe). So, where do you stand relative to the burden of proof on any given topic? On some topics determining where the burden falls is hard, on others, it’s easy. Just ask the people who know better. Say, I don’t know, scientists on scientific questions.
So if your knee-jerk reaction to a scientific question is to question it, then you ought to know that you have a high burden of proof to overcome. Someone please tell George Will:
>Climate Cassandras say the facts are clear and the case is closed. (Sen. Barbara Boxer: “We’re not going to take a lot of time debating this anymore.”) The consensus catechism about global warming has six tenets: 1. Global warming is happening. 2. It is our (humanity’s, but especially America’s) fault. 3. It will continue unless we mend our ways. 4. If it continues we are in grave danger. 5. We know how to slow or even reverse the warming. 6. The benefits from doing that will far exceed the costs.
>Only the first tenet is clearly true, and only in the sense that the Earth warmed about 0.7 degrees Celsius in the 20th century. We do not know the extent to which human activity caused this. The activity is economic growth, the wealth-creation that makes possible improved well-being—better nutrition, medicine, education, etc. How much reduction of such social goods are we willing to accept by slowing economic activity in order to (try to) regulate the planet’s climate?
Hard to know what George Will, famous climate skeptic (see also here), could mean by “clearly true” in this instance. But I think it’s something like “not even I–who read Michael Crichton’s science fiction novel about global warming hysteria–can doubt that one any more.” I know that’s a little mean. But Will doesn’t bother even trying to support his claim–clearly at odds with current qualified scientific consensus–with any evidence (at all–not even bad evidence). Instead he changes the subject:
>We do not know how much we must change our economic activity to produce a particular reduction of warming. And we do not know whether warming is necessarily dangerous. Over the millennia, the planet has warmed and cooled for reasons that are unclear but clearly were unrelated to SUVs. Was life better when ice a mile thick covered Chicago? Was it worse when Greenland was so warm that Vikings farmed there? Are we sure the climate at this particular moment is exactly right, and that it must be preserved, no matter the cost?
That’s an argument from ignorance! Who knows–maybe global warming will be good for us. We could farm in Greenland. Since we can’t tell either way, let’s do nothing.