Science-Based Medicine (SBM) is, as the name plainly states, based upon and in fact dependent on science. So anything that threatens the institutions of science is a threat to SBM. Threats come in many forms – including pseudoscience (science distorted and biased to produce desired outcomes rather than true outcomes), anti-science (attempts at undermining or even replacing science as a method for figuring stuff out), and science-denial (perverting skepticism to deny established science) to name perhaps the top three.

But there is one thing that underlies and reinforces all three of these threats to science, and seems to be growing in power and influence: conspiracy thinking. As a psychological phenomenon this does not refer to just the notion that conspiracies exist, for they certainly do. Rather, it refers to belief in one or more grand conspiracies, a conspiracy so large that it would require hundreds or thousands of people working across institutions, nations, and perhaps even generations to create not just a lie but a false reality. Grand conspiracies are inherently implausible, as the larger they become the more quickly they would be revealed, eventually becoming mathematically impossible. As I like to say, grand conspiracies would tend to collapse in on themselves.

Grand conspiracies are nothing new, but the emergence of various popular and increasingly-implausible conspiracy theories calls out for explanation. The anti-vaccine movement, for example, has always been based on the big conspiracy, that the government (in fact many governments), the medical establishment, hospitals, universities, professional organizations, and pharmaceutical companies are all working together to promote the lie that vaccines are safe and effective. The anti-vaccine grand conspiracy, like any other, gets more implausible the more you think about it. The problem with conspiracy theories is that they need to get bigger and deeper in order to cover their tracks. In this way conspiracy thinking is a positive feedback loop, leading to grander and grander conspiracies.

For vaccines we could ask, why hasn’t any intrepid reporter broken this story? Because they must be in on it. Further, the conspiracy must simultaneously be massive and airtight. The medical establishment must have engineered the illusion that vaccines have significantly reduced many diseases, and then tricked millions of healthcare experts or involved them in the conspiracy. The conspiracy is so far-reaching that it has controlled every single government around the world. None have broken away from its grip.

The grand conspiracy narrative also relies upon an implausible and cynical view of humanity. People are divided into three stark groups:

  • The conspirators, who are simultaneously brilliant and absurdly stupid since they can engineer an unbelievably complex conspiracy but always reveal themselves in silly ways.
  • The enlightened, members of the army of light who sees the conspiracy for what it is and are on a mission to save the world.
  • Everyone else, the “sheeple” who cannot see the conspiracy and remain its victims.

The psychological appeal of being among the enlightened few is clear.

Conspiracy thinking is anathema to science, because it turns the rules of evidence on its head. In the world of grand conspiracies a lack of evidence is simply evidence that there has been a cover-up – no evidence is evidence for the conspiracy. Any positive evidence that contradicts the conspiracy is also more evidence for the conspiracy, because it was planted by the conspirators. Therefore, there is no way to refute the conspiracy. It is immune to evidence which is inherently anti-science.

Even those, like myself, who have taken an interest in the grand conspiracy phenomenon for decades have been surprised by the level they have reached in the last couple of decades. Just when you think that you have seen the pinnacle of conspiracy absurdity, new ground is broken. I used to think that the entire alternative medicine grand conspiracy narrative was as bad as it gets. In this narrative, not only vaccines, but virtually all of modern medicine is a corporate conspiracy. Anyone who defends any science-based practice must be in on the conspiracy, and suppressing the “truth” about natural remedies. (Yes, I still get these e-mails.) So askew of reality is conspiracy thinking that it claims millions of people who have essentially dedicated their lives to the healing profession are hiding the cure for cancer, knowingly injecting poison into children, and laughing all the way to the bank. The CAM conspiracy theory requires an entire profession and their enablers to be guilty of psychopathic evil.

As absurd as all this is, and as jaded as I have become about the limitlessness of human gullibility, I was surprised by the popularity of the Flat-Earth conspiracy. This is the notion that the entire scientific community, along with the aerospace and commercial airline industries, not to mention everyone with a telescope, is engaged in a multi-century conspiracy to convince the world that the Earth is roughly a sphere when in fact it is flat. This is an excellent example of how conspiracies need to become exponentially more absurd as you challenge their premises. If the Earth is flat, then it would collapse under its own gravity. So therefore – gravity must also be a conspiracy. That’s right, gravity.

The Flat-Earth conspiracy is so grand, in fact, that it functions as an ultimate conspiracy. An ultimate conspiracy is one so large that it essentially breaks truth. If the world can be lying about something so fundamental as the shape of the planet, then you cannot believe anything. “They” can be lying about anything and everything, there is no truth, there are no facts, and you can then justify every other conspiracy because no matter how grand they are, they pale in comparison.

It was not surprising, therefore, that the Flat-Earth conspiracy paved the way for Q-Anon – which started as the claim that the Democratic party is made of devil-worshipping pedophiles and that Trump (any day now – better hurry) is going to expose them and bring them to justice. Q-Anon started with this core claim but has metastasized into an all-purpose right-wing grand conspiracy, including anti-vaccine views.

Trying to reverse engineer how conspiracy theories have gotten so out of control in the last two decades should keep psychologists busy for a while. Social media, however, seems to be lurking at the center of this phenomenon. Social media algorithms have created another positive feedback loop, sucking in otherwise typical and even intelligent people into a conspiracy narrative until they cannot tell fact from fiction, and then they can believe anything. This phenomenon is nothing less than an existential threat, including to science and therefore SBM. But more broadly this is a threat to any notion of evidence, logic, facts, and reality. We need to take this threat seriously, and devote time and attention to figuring it out and mitigating it.


Posted by Steven Novella

Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also has produced two courses with The Great Courses, and published a book on critical thinking - also called The Skeptics Guide to the Universe.