After spending enough time around Flat Earthers, anti-vaxxers, intelligent designers, and climate change deniers, one begins to sense a pattern. Their strategies are all the same. Although the content of their belief systems differs, all science denial seems grounded in the same few mistakes in human reasoning. This has been studied by previous researchers such as Mark and Chris Hoofnagle, Pascal Diethelm and Martin McKee, John Cook, and Stephan Lewandowsky, who have come to consensus on five common factors:
- Cherry-picking evidence
- Belief in conspiracy theories
- Reliance on fake experts (and the denigration of real experts)
- Committing logical errors
- Setting impossible expectations for what science can achieve
Together, these provide a common blueprint for science deniers to create a counter-narrative on any topic where they wish to challenge the scientific consensus. The Hoofnagle brothers define science denial as “the employment of rhetorical tactics to give the appearance of argument or legitimate debate, when in actuality there is none.” Why would anyone want to do this? Perhaps for self-interest. Or ideology. Or to conform to a set of political expectations. There are many reasons why someone might wish to create—or might be taken in by—a false reality, when the scientific consensus challenges what they would prefer to believe. We’ll get to that. First, I would like to examine each of the five reasoning errors in more detail, so that we have a better understanding of how denialism is a problem for empirical judgment. Later, I will have more to say about why it might be that a common script lies behind it … and what we can do about it.
Of course, reliance on fake experts, illogical reasoning, and insisting that science must be perfect all seem fairly straightforward, don’t they? It is easy to see what is wrong with them. But what about the problem of cherry-picking evidence? Or belief in conspiracy theories? These go to the heart of scientific judgment, which is supposed to be embedded in a good-faith effort to test one’s theory against reality instead of just trying to confirm what one already wants to believe, or jumping to a conclusion based on no evidence whatsoever. Scientists set out to find the truth, not deny it when it doesn’t conform to their expectations. If an ideologue is completely committed to a theory—dismissing any evidence against it and needing little in its favor—how will they learn from future experience?
It probably won’t surprise you to learn that the flawed reasoning strategy employed by science deniers is firmly rooted in a misunderstanding of how science actually works. In my book The Scientific Attitude, I went over some of these misconceptions in detail. I won’t repeat them here, except to say that one of the hallmarks of science is how it responds to evidence. Scientists care about evidence and are willing to change their minds based on new evidence. This is why science cannot offer proof, but must instead rely on the idea that belief is warranted when a theory has sufficient credible evidence and has survived rigorous testing. With ideology or dogma, it’s another story.