At the same time, Facebook was sharply criticized for a change to its fact-checking policies that critics say enables the spread of climate disinformation. Sander van der Linden, a social psychologist at the University of Cambridge, and cognitive scientist John Cook of George Mason University in Fairfax, Va., helped the company develop a new “myth-busting” unit that debunks common climate change myths — such as that scientists don’t agree that global warming is happening. Courtesy of J. Cook Danielle Da Silva Photography, courtesy of S. van der Linden Researchers John Cook and Sander van der Linden hope to inoculate people against climate change denial messages.