In any situation when there is an unknown, the burden of proof falls on one or both sides. There are many examples of controversial issues, like say abortion where both sides plead their case equally.

In other arguments the burden of proof falls on one side. For example in a court the burden is on the prosecution. In more extreme situations like in the war on terrorism the burden sometimes shifts to Arabs having to prove their innocence. Unfortunate, but that's the way it works in the real world.

With pharmaceuticals the burden is on the drug company to prove they are safe, not on the consumer to prove they are dangerous.

The rule is quite simple. When a wrong decision is sufficiently dangerous the burden falls on one side to prove it is not dangerous. There is not a social situation in the world where this doesn't apply.

The problem with global warming is that potentially it is extremely dangerous. Those who don't believe in it logically should have the burden of proof on them to show it is not dangerous.

To give another example. The USSR was believed to be dangerous because of an unknown military build up that could have been catastrophic if it was true. Therefore the worst case was assumed, and that it was not true was irrelevant. In that case the burden of proof was on the doves not the hawks.

In the war on terror the Republicans never stop saying that we can't take a chance because the danger is so extreme with WMD's.

With global warming though we have an extreme danger with a lot of plausible but unproven data. So this should be an open and shut case of the burden of proof on the polluters to show it is not happening, to be on the safe side.

I have never seen an explanation of this. Why should we take a chance on this global warming happening, whether it is true or not? We wouldn't take a chance on any other comparable problem.