[yequalsx]

We humans are right now conducting the experiment. Despite empirical evidence, data, modeling, and application of our knowledge the effects of green house gases we continue to pump them into the atmosphere on a massive scale. In another 30 - 40 years the experiment will yield conclusive results. Then I suppose global warming deniers like Rush Limbaugh will shrug their shoulders and say, "Well, we now have our experimental evidence."

[batou]

I look forward to the results however I'm not sure they stand as an unbiased controlled experiment and are as factually devoid as the methodology.

Many things are observable but the difference between correlation and causation are somewhat more subtle.

Please note, I'm no denier and think that we should reduce our emissions as they have secondary benefits, fully acknowledge that there is a slight raise in global temperature but to assign a cause is a little premature.

Add to that the incidental political involvement, funding and the 'facts' (of incidentally we have none, nor many viable theories) leads to a logical conclusion that "mu" (neither yes or no) is a better stance to take.