But more generally they helped make popular and respectable the idea that much of science is a sinister scheme concocted by a despotic conspiracy to oppress the people. Mental illness, both Szasz and Laing said, is “a theory not a fact”—now the universal bottom-line argument for anyone, from creationists to climate change deniers to antivaccine hysterics, who prefer to disregard science in favor of their own beliefs.