Bayesianism versus Critical Rationalism

Jayson_Virissimo

I have just rediscovered an article by Max Albert on my hard drive which I never got around to reading that might interest others on Less Wrong. You can find the article here. It is an argument against Bayesianism and for Critical Rationalism (of Karl Popper fame).

Abstract:

Economists claim that principles of rationality are normative principles. Nevertheless,
they go on to explain why it is in a person’s own interest to be rational. If this were true,
being rational itself would be a means to an end, and rationality could be interpreted in
a non-normative or naturalistic way. The alternative is not attractive: if the only argument
in favor of principles of rationality were their intrinsic appeal, a commitment to
rationality would be irrational, making the notion of rationality self-defeating. A comprehensive
conception of rationality should recommend itself: it should be rational to be
rational. Moreover, since rational action requires rational beliefs concerning means-ends
relations, a naturalistic conception of rationality has to cover rational belief formation including
the belief that it is rational to be rational. The paper considers four conceptions
of rationality and asks whether they can deliver the goods: Bayesianism, perfect rationality
(just in case that it differs from Bayesianism), ecological rationality (as a version of
bounded rationality), and critical rationality, the conception of rationality characterizing
critical rationalism.

Any thoughts?

A good nutshell description of the type of Bayesianism that many LWers think correct is objective Bayesianism with critical rationalism-like underpinnings. Where recursive justification hits bottom is particularly relevant. On my cursory skim, Albert only seems to be addressing "subjective" Bayesianism which allows for any choice of prior.

4XiXiDu15y

For people like me who have no clue, if you scroll down a bit here there is a comparison (so you get a vague idea): * Subjective Bayesians emphasize the relative lack of rational constraints on prior probabilities. * Objective Bayesians (e.g., Jaynes and Rosenkrantz) emphasize the extent to which prior probabilities are rationally constrained. More here: And of course Critical rationalism: * Critical rationalism explicitly proposes a third decision rule for rational belief formation: it is rational to believe a hypothesis if it has so far withstood serious criticism better than its competitors.

5Matt_Simpson15y

I'll add that a decent summary of the position espoused in Where recursive justification hits bottom (linked in the grandparent) is that critical rationalism (or something like it) entails objective Bayesianism. It both entails the use of Baye's rule to update on information and it entails a set of correct priors.

1Jayson_Virissimo15y

Thanks for helping me realize that Critical Rationalism and Bayesianism can be compliments rather than substitutes.

2Elliot Temple15y

FYI that is a misleading statement of Critical Rationalism. For one thing, Popper was not a "belief philosopher" so he wouldn't have stated it quite like that. There are a lot of misleading statements about CR floating around. Most come from its opponents trying to make sense of it on their own terms. In trying to formulate it in a way that makes sense given their anti-CR premises, they change it. It's best to read primary sources for this.

It seems to think the problem of the priors does in Bayesianism :-(

Popper seems outdated. Rejecting induction completely is not very realistic.

2Jayson_Virissimo15y

Critical Rationalism has advanced somewhat since Popper. I think Hume would agree.

2timtyler15y

Not very significantly. The revolution happened mostly without them.

5Jayson_Virissimo15y

After reconsidering your statement, I have come to agree.

1Elliot Temple15y

Who do you think advanced CR? I think only David Deutsch has improved on Popper.

2Jayson_Virissimo15y

I had in mind Miller and Deutsch.

2Elliot Temple15y

Which Miller publication or argument?

5Jayson_Virissimo15y

Critical Rationalism: A Restatement and Defense and Out of Error: Further Essays On Critical Rationalism.

1Elliot Temple15y

Thanks I ordered them. I'd only read individual articles of his.

-2[anonymous]15y

Hume would agree because he never accepted the full force of his own argument. He couldn't imagine how people can create knowledge without induction even though he could see that induction is impossible. It took Popper to explain how knowledge can be created without induction.

Anyway, that fact that no human has a starting point as badly flawed as anti-induction doesn't make Bayesianism invalid.

I did not say it makes Bayesianism invalid. I said it doesn't make Popperism invalid or require epistemological pessimism. You were making myth of the framework arguments against Popper's view. My comments on those were not intended to refute Bayesianism itself.

This is exactly we we need induction. It is usually possible to stick any future onto any past and get a consistent history, induction tells us that if we want a probable history we need to make the future and the past resemble each other.

That is a mistake and Popper's approach is superior.

Part 1: It is a mistake because the future does not resemble the past except in some vacuous senses. Why? Because stuff changes. For example an object in motion moves to a different place in the future. And human societies invent new technologies.

It is always the case that some things resemble the past and some don't. And the guideline that "the future resembles the past" gives no guidance whatsoever in figuring out which are which.

Popper's approach is to improve our knowledge piecemeal by criticizing mistakes. The primary criticisms of this approach are that is it is incapable of offering guarantees, authority, justification, a way to force people to go against their biases, etc.. These criticisms are mistaken: no viable theory offers what they want. Setting aside those objections -- that Popper doesn't meet standard too high for anything to meet -- it works and is how we make progress.

Regarding people wanting to find the truth, indeed they don't always. Sometimes they don't learn. Telling them they should be Bayesians won't change that either. What can change it is sorting out the mess of their psychology enough to figure out some advice they can use. BTW the basic problem you refer to is static memes, the theory of which David Deutsch explains in his new (Popperian) book The Beginning of Infinity.

I have no further interest in talking with you if you resort to straw men like this.

Please calm down. I am trying my best to explain clearly. If I think that some of your ideas have nasty consequences that doesn't mean I'm trying to insult you. It could be the case that some of your ideas actually do have nasty consequences of which you are unaware, and that by pointing out some of the ways your ideas relate to some ideas you consciously deem bad, you may learn better.

All justificationist epistemologies have connections to authority, and authority has nasty connections to politics. You hold a justificationist epistemology. When it comes down to it, justification generally consists of authority. And no amount of carefully deciding what is the right thing to set up as that authority changes that.

This connect to one of Popper's political insights which is that most political theories focus on the problem "Who should rule?" (or: what policies should rule?). This question is a mistake which begs for an authoritarian answer. The right question is a fallibilist one: how can we set up political institutions that help us find and fix errors?

Getting back to epistemology, when you ask questions like, "What is the correct criterion for induction to use in step 2 to differentiate between the infinity of theories?" that is a bad question which begs for an authoritarian answer.

All I am saying is your mind was not designed to do philosophical reasoning

My mind is a universal knowledge creator. What design could be better? I agree with you that it wasn't designed for this in the sense that evolution doesn't have intentions, but I don't regard that as relevant.

Evolutionary psychology contains mistakes. I think discussion of universality is a way to skip past most of them (when universality is accepted, they become pretty irrelevant).

Your brain is not well suited to abstract reasoning, it is a fortunate coincidence that you are capable of it at all.

I'd urge you to read The Beginning of Infinity by David Deutsch which refutes this. I can give the arguments but I think reading it would be more efficient and we have enough topics going already.

forcing them to follow rigorous rules.

See! I told you the authoritarian attitude was there!

And there is no mathematical proof of Bayesian epistemology. Bayes' theorem itself is a bit of math/logic which everyone accepts (including Popper of course). But Bayesian epistemology is an application of it to certain philosophical questions, which leaves the domain of math/logic, and there is no proof that application is correct.

The above is not intended as a personal attack

I know. My comments weren't either.

Part 1: It is a mistake because the future does not resemble the past except in some vacuous senses. Why? Because stuff changes. For example an object in motion moves to a different place in the future. And human societies invent new technologies.

The object in motion moves according to the same laws in both the future and the past, in this sense the future resembles the past. You are right that the future does not resemble the past in all ways, but the ways in which it does themselves remain constant over time. Induction doesn't apply in all cases but w... (read more)

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Bayesianism versus Critical Rationalism

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