It comes from Richard Feynman, one of the pre-eminent scientists of modern times, via the Science and Environmental Policy Project:
You cannot prove a vague theory wrong. If the guess that you make is poorly expressed and the method you have for computing the consequences is a little vague then ….. you see that the theory is good as it can’t be proved wrong. If the process of computing the consequences is indefinite, then with a little skill any experimental result can be made to look like an expected consequence.
Which is exactly what we have seen from the global warming alarmists. They admit no set of facts that would falsify their hypothesis; they make no predictions that prove true; and no matter what happens, it can retroactively be fitted into their vague and therefore accommodating theory. To take just one example: the models on which all climate alarmism is based predict that global warming will result in fewer extreme weather events, because the temperature differential between the Equator and the poles will narrow. No matter: when it became politically expedient to blame any adverse weather on global warming, the alarmists were happy to ignore their models and join in.
Ken Haapala, Executive Vice President of SEPP, elaborates on Feynman’s insight:
The above quote is taken from a lecture by Richard Feynman…. The quote goes to the nature of what is now climate science as practiced by the climate establishment. Global warming caused by human carbon dioxide (CO2) emissions has become climate change and extreme weather events, as if they have never occurred before. Climate change has been happening for hundreds of millions of years, and humans have long termed unusual events as extreme. There is nothing happening today that cannot be found in the historic record. The climate establishment knows this, and places artificial constraints on the historic record. Such actions can be seen in the reports of the UN Intergovernmental Panel on Climate Change (IPCC), which places constraints on the historic record by statements such as “since 1950” or “after the industrial revolution” (about 1750, leaving out the worst of the Little Ice Age and the prior warm period).
The entire effort plays to politicians who wish to appear to be great leaders in fighting something – especially if the enemy cannot be defined; therefore, success cannot be measured. On this largely imaginary battle, reputations are built and significant moneys are spent. As Richard Lindzen, MIT Professor Emeritus of Meteorology, wrote to SEPP: We should … “express thanks for the failures of Kyoto and Copenhagen. Had the proposed regulatory regimes been implemented and had CO2 emissions decreased, the ‘pause’ would certainly have been attributed to the regulations. Politicians and environmentalists would be declaring the science to be truly ‘settled.’”
That is exactly right. I think the alarmists knew all along that there would be no significant change in the Earth’s climate as a result of CO2 emissions. I think their plan was to force the adoption of some mild restrictions on CO2 emissions–nowhere near enough to make any perceptible difference, according to their own models–and then, as the years went by and no catastrophic climate change occurred, claim the credit. Happily, they have been foiled because even the insufficient measures they advocated were so economically ruinous that no country, whether autocratic or democratic, was willing to implement them. And, of course, the expected result–no catastrophic global warming–is occurring. Which is why the alarmists are in such disarray, and resort to personal attacks and lawsuits (Michael Mann, I mean you) to keep their bogus theories alive.