Yes I think your use of bias to mean what I’ve called core beliefs is confusing given cognitive biases. But there is another equation. I think the strength of a belief (the degree of certainty someone claims for the truth or falsity of it) has 2 components. First the evidence they claim and second the importance to them that the belief is true or false. People believe true things and believe false things anywhere on these scales. When I use core beliefs I mean those beliefs that are far along the importance scale although they could be beliefs about almost anything. So someone can believe falsely that Rio de Janeiro is the capital of Brazil or falsely that Trump won the 2022 election but attach very different importance to these two beliefs. The problem is what happens when evidence and importance clash, which is something I think a conspiracy theory can resolve. Although it seems unlikely I would not even dismiss the possibility that someone would believe in a conspiracy to hide Rio as the true capital of Brazil!

Those who cite critical thinking as the solution to the problem of false beliefs are I think missing this other dimension. Critical thinking can allow you to address the evidence someone claims but it does not address the importance they attach to the belief. Even when someone has no grounds to believe something they can still believe it. I don’t know the answer here though, I’m merely questioning whether critical thinking is enough on it’s own. I have a favoured analogy here. The advocates of critical thinking (only) sometimes seem to me like the advocates of abstinence only as a way to prevent sexually transmitted diseases. I’m not suggesting that abstinence only doesn’t work, just that I don’t think it’s something people do all that well!.

Thanks for taking the time to reply - it’s a topic that interests me too. However I’ve come to slightly different conclusions. First I think that conspiracy theories can be accounted for by the psychological function they perform rather than the fact people are susceptible to cognitive biases. In this I mean they make you feel better or perhaps resolve a conflict (which also feels good). Some examples:

1. Covid origin conspiracies or anti-Semitic conspiracies give the holder special knowledge or prestige but can also give a sense of order which may be reassuring (over randomness).
2. Jan 6th conspiracies among Republicans allow the holder to avoid unpleasant facts about Trump or some of his supporters. These would be difficult to reconcile with their worldview but conspiracy theories provide a way out. Claims about voting help them too.

This describes what people get out of believing in conspiracy theories but it doesn’t say how belief in conspiracy theories is maintained when there is so little (no) evidence for them. In this I think it’s possible that (cognitive) biases do not cause people to believe conspiracy theories but are instead utilised (not necessarily deliberately) to maintain the conspiracy belief. Here I’d generalise this to other deeply held beliefs, which is where individuals like Oz come in (although many tip over into outright conspiracism too).

In short people try to maintain a core set of beliefs about the world and desire consistency from events, because maintaining core beliefs feels good and having a world of facts that do not contradict them feels good too. Cognitive biases work to achieve this. However knowledge of cognitive biases and arguments can also be used to attack (all the) counter evidence/arguments. In this way otherwise thoughtful, intelligent people can cling to conspiracy theories. Educating them on critical thinking is therefore not always effective because the critical thinking strategies can be employed with a desired goal (to maintain those core beliefs). It can therefore be hard in practice for critical thinking to overcome biases because we can be biased in our critical thinking too.

Examples like these are comforting but others are much less so. Most recently Dr Oz has been in the news after losing a midterm race. At the start of his career he was lauded as an academic surgeon, but he has since embraced a number of ideas that led David Gorski to label him America’s Quack. That highly qualified individuals with impressive credentials can nevertheless adopt pseudoscientific beliefs has even led to the idea of a Nobel disease:

https://en.m.wikipedia.org/wiki/Nobel_disease

The point is that while various attributes (such as education) provide some protection from unsupported beliefs, it is not perfect. In fact it may even be worse than this, since Uscinski is quoted in the article as claiming we all probably entertain some conspiracy theories.