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curi comments on Bayesianism versus Critical Rationalism - Less Wrong
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I apologise for this, but I really don't see how anyone could go through those studies without losing all faith in human intuition.
The text can be found online. My browser (Chrome) wouldn't open the files but you may have more luck.
Part of the reason for length is that probability theory has a number of axioms and he has to prove them all. The reason for the two chapter split is that the first chapter is about explaining what he wants to do, why he wants to do it, and laying out his desiderata. It also contains a few digressions in case the reader isn't familiar with one or more of the prerequisites for understanding it (propositional logic for example). All of the actual maths is in the second chapter.
I agree to the explicit meaning of this statement but you are sneaking in connotations. Let us look more closely about what 'authoritarian' means.
You probably mean it in the sense of centralised as opposed to decentralized control, and in that sense I will bite the bullet and say that thinking should be authoritarian.
However, the word has a number of negative connotations. Corruption, lack of respect for human rights and massive bureaucracy that stifles innovation to name a few. None of those apply to my thinking process, so even though the term may be technically correct it is somewhat intellectually dishonest to use it, something more value-neutral like 'centralized control' might be better.
I will confess that I am not familiar with the whole of Popper's viewpoint. I have never read anything written by him although after this conversation I am planning to.
Therefore I do not know whether or not I broadly agree or disagree with him. I did not come here to attack him, originally I was just responding to a criticism of yours that Bayesianism fails in a certain situation
To some extent I think the approach with conjectures and criticisms may be correct, at least as a description of how thinking must get off the ground. Can you be a Popperian and conjecture Bayesianism?
The point that I do disagree with is the proposed asymmetry between confirmation and falsification. In my view neither the black swan or the white swan proves anything with certainty, but both do provide some evidence. It happens in this case that one piece of evidence is very strong while the other is very weak, in fact they are pretty much at opposite extremes of the full spectrum of evidence encountered in the real world. This does not mean there is a difference of type.
All else being equal, yes. Other factors, such as real-world results might take precedence. I also doubt that any philosophy could manage without either circularity or assumptions, explicit or otherwise. As I see it when you start thinking you need something to begin your inference, logic derives truths form other truths, it cannot manufacture them out of a vacuum. So any philosophy has two choices:
Either, pick a few axioms, call them self evident and derive everything from them. This seems to work fairly well in pure maths, but not anywhere else. I suspect the difference lies in whether the axioms really are self evident or not.
Or, start out with some procedures for thinking. All claims are judged by these, including proposals to change the procedures for thinking. Thus the procedures may self-modify and will hopefully improve. This seems better to me, as long as the starting point passes a certain threshold of accuracy any errors are likely to get removed (the phrase used here is the Lens that Sees its Flaws). It is ultimately circular, since whatever the current procedures are they are justified only by themselves, but I can live with that.
Ideal Bayesians are of the former type, but they can afford to be as they are mathematically perfect beings who never make mistakes. Human Bayesians take the latter approach, which means in principle they might stop being Bayesians if they could see that for some reason it was wrong.
So I guess my answer is that if a position didn't endorse circular arguments, I would be very worried that it is going down the unquestionable axioms route, even if it does not do so explicitly, so I would probably not prefer it.
Notice how it is only through the benefits of the second approach that I can even consider such a scenario.
I haven't got any faith in human intuition. That's not what I said.
OK fair enough.
Oh the book is here: http://bayes.wustl.edu/etj/prob/book.pdf
That was easy.
I don't know the etiquette or format of this website well or how it works. When I have comments on the book, would it make sense to start a new thread or post somewhere/somehow?
You can conjecture Bayes' theorem. You can also conjecture all the rest, however some things (such as induction, justificationism, foundationalism) contradict Popper's epistemology. So at least one of them has a mistake to fix. Fixing that may or may not lead to drastic changes, abandonment of the main ideas, etc
That is a purely logical point Popper used to criticize some mistaken ideas. Are you disputing the logic? If you're merely disputing the premises, it doesn't really matter because its purpose is to criticize people who use those premises on their own terms.
Agreed.
I think you are claiming that seeing a white swan is positive support for the assertion that all swans are white. (If not, please clarify). If so, this gets into important issues. Popper disputed the idea of positive support. The criticism of the concept begins by considering: what is support? And in particular, what is the difference between "X supports Y" and "X is consistent with Y"?
Questioning this was one of Popper's insights. The reason most people doubt it is possible is because, since Aristotle, pretty much all epistemology has taken this for granted. These ideas seeped into our culture and became common sense.
What's weird about the situation is that most people are so attached to them that they are willing to accept circular arguments, arbitrary foundations, or other things like that. Those are OK! But that Popper might have a point is hard to swallow. I find circular arguments rather more doubtful than doing without what Popperians refer to broadly as "justification". I think it's amazing that people run into circularity or other similar problems and still don't want to rethink all their premises. (No offense intended. Everyone has biases, and if we try to overcome them we can become less wrong about some matters, and stating guesses at what might be biases can help with that.)
All the circularity and foundations stem from seeking to justify ideas. To show they are correct. Popper's epistemology is different: ideas never have any positive support, confirmation, verification, justification, high probability, etc... So how do we act? How do we decide which idea is better than the others? We can differentiate ideas by criticism. When we see a mistake in an idea, we criticize it (criticism = explaining a mistake/flaw). That refutes the idea. We should act on or use non-refuted ideas in preference over refuted ideas.
That's the very short outline, but does that make any sense?
Fully agreed. In principle, if Popper's epistemology is of the second, self-modifying type, there would be nothing wrong with drastic changes. One could argue that something like that is exactly how I arrived at my current beliefs, I wasn't born a Bayesian.
I can also see some ways to make induction and foundationalism easer to swallow.
A discussion post sounds about right for this, if enough people like it you might consider moving it to the main site.
This is precisely what I am saying.
The beauty of Bayes is how it answers these questions. To distinguish between the two statements we express them each in terms of probabilities.
"X is consistent with Y" is not really a Bayesian way of putting things, I can see two ways of interpreting it. One is as P(X&Y) > 0, meaning it is at least theoretically possible that both X and Y are true. The other is that P(X|Y) is reasonably large, i.e. that X is plausible if we assume Y.
"X supports Y" means P(Y|X) > P(Y), X supports Y if and only if Y becomes more plausible when we learn of X. Bayes tells us that this is equivalent to P(X|Y) > P(X), i.e. if Y would suggest that X is more likely that we might think otherwise then X is support of Y.
Suppose we make X the statement "the first swan I see today is white" and Y the statement "all swans are white". P(X|Y) is very close to 1, P(X|~Y) is less than 1 so P(X|Y) > P(X), so seeing a white swan offers support for the view that all swans are white. Very, very weak support, but support nonetheless.
(The above is not meant to be condescending, I apologise if you know all of it already).
This is a very tough bullet to bite.
One thing I don't like about this is the whole 'one strike and you're out' feel of it. It's very boolean, the real world isn't usually so crisp. Even a correct theory will sometimes have some evidence pointing against it, and in policy debates almost every suggestion will have some kind of downside.
There is also the worry that there could be more than one non-refuted idea, which makes it a bit difficult to make decisions. Bayesianism, on the other hand, when combined with expected utility theory, is perfect for making decisions.
When replying it said "comment too long" so I posted my reply here:
http://lesswrong.com/r/discussion/lw/552/reply_to_benelliott_about_popper_issues/