Bryan writes,

Sincere question: Have you personally reviewed the evidence on smoking, Arnold? I haven’t. I believe that smoking causes cancer based on scientific consensus.

…Still, Arnold seems to be saying that you should base all your beliefs on direct examination of the evidence, and ignore expert consensus. I just can’t buy that – and I wonder if Arnold really buys it either. Arnold?

The reason I have not reviewed the evidence on smoking and lung cancer is that I trust my statistical intuition, which tells me that this is an easy situation in which to obtain reliable data. So if the people who have looked at the data come to strong conclusions, I believe those conclusions are robust.

On global warming, I see a chaotic system with a ratio of potential explanatory variables to data points that far exceeds one. My intuition is that the climate models are highly unreliable.

Another way of saying this is that I believe that the scientific consensus on smoking is robust. I believe that the scientific consensus on global warming is fragile.

I believe that it is silly to trust all consensus estimates in all scientific fields equally. I imagine that with a bit of introspection, Bryan would agree.