What really confuses me is that many in this so called "rationalist" clique discuss Bayesianism as an "ism", some sort of sacred, revered truth. They talk about it in mystical terms, which matches the rest of their cult-like behavior. What's the deal with that?
That's specific to Yudkowsky, and I think that's just supposed to be humor. A lot of people find mathematics very dry. He likes to dress it up as "what if we pretend math is some secret revered knowledge?".
I personally don't have that much of an interest in this topic, so I can't critique them for quality myself, but they may at least be of relevance to you.
Popper requires you to posit null hypotheses to falsify (although there are different schools of thought on what exactly you need to specify in advance [1]).
Bayesianism requires you to assume / formalize your prior belief about the subject under investigation and updates it given some data, resulting in a posterior belief distribution. It thus does not have the clear distinctions of frequentism, but that can also be considered an advantage.
Popperians claim that positive justification is impossible.
Popperians claim.Induction doesn't exist (or at least , matter in science)
Popper was prepared to consider the existence of Propensities objective.probabilities, whereas Bayesians, particularly those who follow Jaynes believe in determinism and subjective probability.
Popperian refutation is all or nothing, whereas Bayesian negative information is gradual.
In Popperism, there can be more than one front running or most favoured theory, even after the falsifiable ones have been falsified, since there aren't quantifiable degrees of confirmation.
For Popper and Deutsch, theories need to be explanatory, not just predictive. Bayesian confirmation and disconfirmation only target prediction directly -- if they are achieving explanation or ontological correspondence , that would be the result of a convenient coincidence.
For Popperians, the construction of good theoretical conjectures is as important as testing them. Bayesian seem quite uninterested in where hypotheses come from.
For Deutschians, being hard-to-vary is the preferred principle of parsimony. For Yudkuwsians, it's computation complexity.
Error correction as something you actually do. Popperians like to put forward hypotheses that are easy to refute. Bayesians approve theoretically of "updating", but dislike objections and criticisms in practice.
(Long term) prediction is basically impossible . More Deutsch than Popper -- DD believed that the growth and unpredictability of knowledge . The creation of knowledge is so unpredictable and radical that long term predictions cannot be made. Often summarised to "prediction is impossible". Of course , Bayesians are all about prediction --but the predictive power of Ates tends only to be demonstrated in you models, where the ontology isn't changing under your feet. Their AI I predictions are explicitly intuition based.
Optimism versus Doom. Deutsch is highly optimistic that continuing knowledge creation will change the world for the better (a kind of moral realism is a component of this). Yudkowsky thinks advanced AI is our last invention and will kill us all.*
Hmm, what epistemological propositions of Popper's do you think they're missing? To the extent that I understand the issues, they're building on Popper's epistemology, but by virtue of having a more rigorous formulation of the issues, they resolve some of the apparent contradictions in his views.
Most of Popper's key points are elaborated on at length in blog posts on LessWrong. Perhaps they got something wrong? Or overlooked something major? If so, what?
(Amusingly, you seem to have avoided making any falsifiable claims in your comment, while implying that you could easily make many of them...)
It's just "dethroning" in the sense that QED dethroned Maxwellian classical electrodynamics; it provides additional precision and shows how to correct the more limited theory in the cases where it gives obviously implausible results.
From the page, the only point in the extensive discussion of Popper where it disagrees with (its own explanation of) Popper's ideas:
> On the other hand, Popper’s idea that there is only falsification and no such thing as confirmation turns out to be incorrect. Bayes’ Theorem shows that falsification is very strong evidence compared to confirmation, but falsification is still probabilistic in nature; it is not governed by fundamentally different rules from confirmation, as Popper argued.
Popper's idea that confirmatory evidence has no value at all is obviously implausible. Some obviously implausible things turn out to be true anyway, since the universe is not constrained by our imaginations, but not this one; as the page clearly shows, we know that this particular implausible result is slightly false, and we can use Bayesian probability to calculate exactly how wrong.
I've answered your question, because I think that's what a bare minimum level of courtesy demands, but you keep evading mine. What epistemological propositions of Popper's do you think they're missing?
The counterpoint here is that in practice, humility is only found in the best of frequentists, whereas the rest succumb to hubris (i.e. the cult of irrelevant precisions).
I actually think that their main problem is the belief that they can learn everything about the world by reading stuff on the Web. You can't understand everything by reading blogs and books, in the end, some things are best understood when you are on the ground. Unironically, they should go touch the grass.
One example for all. It was claimed that a great rationalist policy is to distribute treated mosquito nets to 3rd-world-ers to help eradicate malaria. On the ground, the same nets were commonly used for fishing and other activities, polluting the environment with insecticides. Unfortunately, rationalists forgot to ask people that live with mosquitos what they would do with such nets.
In my opinion, there can’t be a meaningful distinction made between rational and irrational without Popper.
Popper injects an epistemic humility that Bayesianism, taken alone, can miss.
I think that aligns well with your observation.