Or why climate skeptics are wrong
At some point in the history of all scientific theories, only a minority of scientists—or even just one—supported them, before evidence accumulated to the point of general acceptance. The Copernican model, germ theory, the vaccination principle, evolutionary theory, plate tectonics and the big bang theory were all once heretical ideas that became consensus science. How did this happen?
An answer may be found in what 19th-century philosopher of science William Whewell called a “consilience of inductions.” For a theory to be accepted, Whewell argued, it must be based on more than one induction—or a single generalization drawn from specific facts. It must have multiple inductions that converge on one another, independently but in conjunction. “Accordingly the cases in which inductions from classes of facts altogether different have thus jumped together,” he wrote in his 1840 book The Philosophy of the Inductive Sciences, “belong only to the best established theories which the history of science contains.” Call it a “convergence of evidence.”
Consensus science is a phrase often heard today in conjunction with anthropogenic global warming (AGW). Is there a consensus on AGW? There is. The tens of thousands of scientists who belong to the American Association for the Advancement of Science, the American Chemical Society, the American Geophysical Union, the American Medical Association, the American Meteorological Society, the American Physical Society, the Geological Society of America, the U.S. National Academy of Sciences and, most notably, the Intergovernmental Panel on Climate Change all concur that AGW is in fact real. Why? (continue reading…)