I’ve always wondered how people can believe in conspiracy theories. Things like “the Earth is flat”, “the CIA is spying on people with 4th dimension tech”, or “the world is secretly run by lizard people” just seem so insanely implausible that anybody who can reason slightly should be able to see through and reject them. Or so I thought. I mean yes, there are the usual reasons that people can get sucked into various ridiculous narratives, such as social media filter bubbles, and the fact that people (even the educated, intelligent ones) typically suck at thinking rationally. But after some reflections on how I acquire knowledge, it occurred to me that even at the simplest philosophical level, it’s very easy to believe in conspiracy theories.

The epistemological foundation of our society is trust. Apart from a few very basic things (mostly about ourselves), almost everything we come to know originate from someone else. We know that the speed of light is constant in all frames of reference, but (almost) none of us have actually experimentally confirmed it, we just believe it. We know that dinosaurs roamed the planet millions of years ago, but none of us have seen them. Small groups of experts tell us what to believe in each of their respective subject areas, and we just take their word for granted, because of trust. That trust ultimately relies on the following two things:

1. Knowledge can be verified by anyone (no knowledge is exclusive to anyone)
2. People are highly incentivized to invalidate important, widely believed knowledge, often with social (fame, respect) and financial (money) payoffs

And for the most part, this system works well. I believe that the speed of light is constant even though I never did any experiments to verify it, because I know that anyone could do the experiment, and should the claim turn out to be false, the person who can show it would be so famous that everyone would want to try to disprove it. The fact that I have not heard of any successful such invalidation attempts indicates to me that I can trust this claim. This is pretty much how we know almost everything we know that does not come from our own subjective experiences.

We have gotten so used to this system of trust that it’s mostly invisible to us. We just trust and believe things that experts say, as long as we don’t hear too much credible opposing opinions. But the system is actually very fragile, and can come crashing down if either one of the two conditions above collapses. Conspiracy theories attack and undermine both of these points, and are very effective at doing so.

In most conspiracy narratives, the “real”, “true” knowledge is secret, and cannot be validated by just anyone. Only the handful of people who’ve been to space can verify the shape of the Earth. Only the few people who got abducted (i.e. chosen) by the aliens know the secrets to the 4th dimension. Only the small council of the real lizard people know how the world is actually run. When the pool of people who could invalidate a claim becomes small (e.g. only NASA), the fact that we haven’t heard of much credible opposing opinions becomes less of a signal for the accuracy of the information (and more about how privileged the validation mechanism is).

The incentives for people to expose false narratives is also removed by conspiracy theories. In fact, the incentives are strongly aligned the other way. No lizard person would want to expose the truth to the world, because then he/she would no longer be running the world. A common counter argument for some popular conspiracy theories is one of coordination: you can’t possibly coordinate tens of thousands of people involved to all keep quiet, someone will blow the whistle sooner or later! But when everyone who knows the “truth” has so much more to lose when compared to the gains for exposing the secrets, it becomes not only plausible, but likely, to successfully coordinate such large scale secret-keeping operations.

When you remove the two conditions required for the trust in our system of knowledge acquisition, anything becomes easily believable, even for rational people. I think this is one of the key reasons that conspiracy theories are so alluring. The real question to ask now is actually why don’t most people believe in conspiracy narratives?