Say you have some driver that causes a temperature increase. You have a mix of positive and negative feedback mechanisms. Let's assume that there is only negative feedback for argument's sake. In this case we would expect that the driver that increases temperature is counteracted somewhat by the negative feedback, and the temperature settles at some higher level. To me, it seems extremely unlikely that a negative feedback could causes temperature to fall to a lower level. This is like saying that applying heat to a pot of water causes the water to cool, since energy is lost to evaporation.
Granted there are far more complex mechanisms at play with the climate, but it seems that people who dispute AGW are relying on these complex feedback mechanisms to work in their favour. Perhaps a bit of Occam's razor could be applied at this point?
Hopefully this post isn't too incoherent, illogical, or unscientific.
By the way, I don't think you should give too much credibility to that petition project that allegedly has 30000 scientists and 10000 Ph.Ds on board. I've posted about this previously here.
Also, re Freeman Dyson, you might be interested to know that he is pro AGW. He just dislikes the climate models and media portrayal of AGW skeptics.
