I suppose Berkeley physicist Richard Muller is a fool for putting together a team that included a Nobel Prize winning scientist, revisiting all the data on climate change to date, and coming to the same conclusion as the current scientific consensus: the globe is warming, and carbon dioxide is the cause.
Muller sees no other plausible alternative thesis–indeed, none is ever consistently on offer. No other thesis accounts for all of the converging lines of evidence better than the current scientific consensus.
So Muller, in discovering this, is obviously a fool.
Global warming denialists, on the other hand, are not at all foolish, for they read the Rush Limbaugh funded American Thinker website for the lowdown on global warming.
And though global warming denialists have no competing alternative thesis that accounts for all of the converging lines of evidence better than carbon dioxide as the cause of global warming, they are in need of none. Instead, they can simply shift among a menu of theses, briefly offering one thesis, then another.
The alternative thesis, in other words, can be the kitchen sink: maybe global warming is caused by volcanoes; and if not volcanoes, maybe it’s the sun; and if not the sun, maybe it’s not happening at all. Maybe the scientists are involved in a conspiracy to promote a hoax, etc. In any case, it couldn’t possibly be the thing that happens to account for the converging lines of evidence most directly and simply: carbon dioxide from human activity. Of that, they’re 100% certain.
William of Occam was a fool, Richard Muller is a fool–but AM talk radio? Nobody’s fool.