"It is difficult to get a man to understand something when his salary depends upon his not understanding it."
Among the ideologues in the climate change denial camp, this quote has several strikes against it. First, it was penned by the Pulitzer Prize winning journalist Upton Sinclair, a socialist firebrand whose early investigative journalism led to the passage of the Pure Food and Drugs Act and the Meat Inspection Act, both in 1906.
A journalist, a socialist, an advocate for regulating the free market; actually, that's three strikes right there.
Worse still, the quote warranted a two-page spread in Al Gore's book, An Inconvenient Truth , a fact that is guaranteed to rile those defending America's right to be wrong on climate change.
But leaving aside the political connections, consider the quote on its own merits. Does it make sense? Does it explain why objectively intelligent people like Financial Post Editor Terrance Corcoran or National Center for Public Policy Research President Amy Ridenour tie themselves up in such elegant knots trying not to believe in climate change?
There is, in the executive offices of ExxonMobile or Peabody Energy, an evident disregard for the evidence  - a ruthless disregard. But among the think-tankers and contrarian scientists - maybe even in the writings of Corcoran and Ridenour - you can sometimes see a flicker of real sincerity, so desperately do they want to believe what Exxon or the Scaife or Koch  foundations tell them to believe.
If Scaife, Koch or Exxon really cared about science - if they really were interested in the truth about climate change - you'd think that they would invest in scientific research, working hard to ensure that the researchers' credentials were impeccable. Instead, they fund policy hothouses like the Cato Institute  or the George C. Marshall Institute , or Ridenour's NCPPR . They fund "scientists" like Pat Michaels  or Sallie Baliunas  - scientists whose current publications appear not in peer-reviewed journals, but in think-tank brochures and in the mainstream press.
It is, indeed, difficult to get a man - or a woman - to understand something when his - of her - salary depends upon not understanding it. That explains the committed contrarians. For the rest of us, the science isn't that hard.
Climate change is a problem; and there is still evidence that we can fix it if we try. Let's.