As we have said, this op-ed by George Will may take a while to sort out (luckily today he did some reportage on the sorry state of Illinois politics). Having already confused science fiction with science fact and having grossly exaggerated the amount of conflict among present day scientists concerning global warming, Will argues that no one is in a position to know whether it would be a bad thing:

>In fact, the Earth is always experiencing either warming or cooling. But suppose the scientists and their journalistic conduits, who today say they were so spectacularly wrong so recently, are now correct. Suppose the Earth is warming and suppose the warming is caused by human activity. Are we sure there will be proportionate benefits from whatever climate change can be purchased at the cost of slowing economic growth and spending trillions? Are we sure the consequences of climate change — remember, a thick sheet of ice once covered the Midwest — must be bad? Or has the science-journalism complex decided that debate about these questions, too, is “over”?

As a commenter pointed out a few days ago, Will distorted the scientific claims about “global cooling” in the articles he cites. But if we leave that aside, we find in the above passage a more straightforward instance of the fallacy of ignorance. Say one grants that we can’t be certain that global warming (with the consequent rise in the waters and so forth) is a bad thing. It certainly does not follow from that fact alone that we should, as Will argues here and elsewhere, *do nothing.* To do nothing is to conclude that global warming it’s *not* a bad thing–thus the fallacy.

To me it seems that a cautious–or even conservative–individual would conclude that it’s best to be on the safe side and cut back on all of those nasty pollutants, which, by the way, are bad for innumerable other reasons.