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Why is it so hard to be rational?

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Re: Why is it so hard to be rational?

#111
post #14

I maintain that it isn't just hard, it is computationally impossible. We should all know that given a belief about the world, and evidence, Bayes' Theorem describes how to update our beliefs. But what if we have a network of interrelated beliefs? That's called a Bayesian net, and it turns out that Bayes' Theorem also prescribes a unique answer. However, unfortunately, it turns out that working out that answer is NP-h…

Why bother reasoning with NP-hardness when you can just invoke incompleteness? No brain power limitations are needed.

Re: Why is it so hard to be rational?

#112

Earlier quoted context omitted.

The rational approach is to acknowledge that you do not have sufficient information to proceed, or acknowledge the various assumptions (better word than “belief) that you are using. If you are using contradicting assumptions, then you should probably check to see if you are doing so because you want the conclusion that you are getting from the assumption.

We make decisions based on imperfect information and conflicting values every day. We generally can’t wait until we have sufficient information to proceed.

That does not require using conflicting assumptions though.

Re: Why is it so hard to be rational?

#113
post #40

Earlier quoted context omitted.

That's why it's called "less wrong". The goal isn't to be perfect, the goal is to do better. To be less wrong.

I wouldn’t be surprised to learn that even being less wrong is NP-hard.

The saving grace of being able to survive in the universe is that it's possible to climb up NP hard problems far enough to get real results with hard work.

Re: Why is it so hard to be rational?

#114
post #48

Earlier quoted context omitted.

Well, it depends on the topic. Choosing rationally between the most green of two tomatoes is easy. You are limited by your ability to distinguish colors but you can still decide rationally. Not all questions have answers, if you want to be rational when you are asked to answer those question, you can just say "I dont know" At the beginning of the pandemic, when politics were saying mask dont work. You could just say,…

> You could just say, well, if we transmit covid by air, then putting something in front of my mouth is going to decrease the spread. That's what is being rational. If I squint at a statement like this, I guess it could be called rational, but it is certainly not rigorous or convincing. You brush over too much and are making lots of assumptions. Are these statements rational? The sun is warm, so if I climb a ladder I…

I think yes, you can call those statements rational, but that just gets at an additional level of difficulty here. Bayes only gets you so far as holding a belief with maximum probability it is true, given some level of seen evidence. To actually get maximally probably true beliefs without the qualification, you need to actually gather more evidence. In some cases, that may just mean accumulating knowledge that other people already generated, but in some cases, you may need to generate knowledge from scratch. The ability to do that may be severely bounded by resource and time constraints. One person can't personally do all science, so now you need division of labor and assignment of workers to efforts, so you need optimal matching and scheduling algorithms. These are theoretically not computationally intractable, but the algorithms rely upon pre-existing accurate ability and preference ranking, so now you need to go back to information gathering and suddenly you have a bootstrapping problem here that feeding your algorithm the data it needs to tell you how to gather data in the first place requires you to gather data first.

Re: Why is it so hard to be rational?

#115
post #104

I think there is a simpler explanation that draws from evolutionary theory: being excessively rational is not a good survival strategy, be it in the distant past or today. If our ancestors would have made the rational assessment that there is unlikely to be a predator hiding behind the bush, that would have worked only as long as it worked, until one day they got eaten. Irrationally overestimating threats and risks i…

Humans operate by doing, then rationalizing, and much of the attempts at rational thought here demonstrate how easy it is to fool ourselves into thinking we are being rational, when really we are acting on feelings and delusions and then constructing what feels like a rational argument that we originally had - but falls apart upon analysis.

In the past, it is a rational concern to be worried about being jumped by a predator from behind a bush, and if you don’t know if or if not there is a predator, it is perfectly rational to be worried about such a concern!

Same with diseases and causes when you don’t know what is causing them, etc.

It’s a tendency to dismiss older concerns from a time when there was a severe lack of information as irrational, where when you know your limits and see the results, there is no other rational way to behave except to be concerned or avoid those things. While also not rational to believe clearly contradictory religious dogma that covers the topic, it is rational to follow or support it when it has clear alignment with visibly effective methods encoded in it for avoiding disease and other problems.

Re: Why is it so hard to be rational?

#116
post #14

I maintain that it isn't just hard, it is computationally impossible. We should all know that given a belief about the world, and evidence, Bayes' Theorem describes how to update our beliefs. But what if we have a network of interrelated beliefs? That's called a Bayesian net, and it turns out that Bayes' Theorem also prescribes a unique answer. However, unfortunately, it turns out that working out that answer is NP-h…

Nobody is disputing this. You can, however, clearly be more or less 'rational', adopt better or worse heuristics, etc. which is what you attempt to get from reading LessWrong or Kahneman.

Re: Why is it so hard to be rational?

#117
post #109
post #77

Earlier quoted context omitted.

Ironically, some of the most irrational people I know are the ones who profess to hew to rationality, to the point where, in certain circles, "rationality" has become a sort of cult. This is particularly evident in militant anti-theism (whose adherents insist that the only possible explanation for someone believing in God is that they are idiots or otherwise mentally deficient), hard-core libertarians (who, ironicall…

How do you know that they are the ones who are being irrational here, and not you? This is a serious question. We should always challenge our preconceptions. To take your examples: 1. Traditional Judeo-Christian religions all claim we should believe because of claims made in holy books of questionable provenance, held by primitive people who believed things like (for example) disease being caused by demons. What rati…

I kind of intended that comment to be ironic self-deprecating humor because, of course, I have no way of knowing whether or not I'm being irrational. Irrational people think they're rational, and so the fact that I think I'm rational does not mean that I am. But it's likewise for everyone. The real point is that everyone ought to have a little more humility about their own rationality (especially all the idiots who are downvoting my original comments. Now they are being totally irrational!)

Re: Why is it so hard to be rational?

#118
post #14

I maintain that it isn't just hard, it is computationally impossible. We should all know that given a belief about the world, and evidence, Bayes' Theorem describes how to update our beliefs. But what if we have a network of interrelated beliefs? That's called a Bayesian net, and it turns out that Bayes' Theorem also prescribes a unique answer. However, unfortunately, it turns out that working out that answer is NP-h…

Not mention we don't actually know with certain the probability of even simple things. The average person is almost never reasoning about simple, repeatable sequences of events. You know there's a chance of your car breaking down each day but you don't know the probability of that event and yet you still deal with that possibility.

Re: Why is it so hard to be rational?

#119
post #97
post #86

Earlier quoted context omitted.

First, there is active research and we demonstrably have learned something. See https://aricjournal.biomedcentral.com/articles/10.1186/s1375... , https://www.nature.com/articles/s41598-020-72798-7 , and https://www.pnas.org/content/118/4/e2014564118 for several examples. Second, your simplistic analysis demonstrated that you, personally, are ignorant of the real tradeoffs involved in whether masks work. Wearing a mas…

…and as they mentioned, we knew that masks work already.

The quality of our evidence is easy to misjudge in retrospect.

The last opportunity to study the effectiveness of mandating low-quality masks in preventing community spread during a pandemic was around a century old. (Literally, the Spanish Flu epidemic.) In the meantime a lot of new and untried modeling tools were in use, as well as updated disease models, and lots of reasons to question old data.

See https://www.albertahealthservices.ca/assets/info/ppih/if-ppi... for an idea of what was reasonable for educated specialists in public health to believe. Note phrases like, "There was agreement that although the evidence base is poor, the use of masks in the community is likely to be useful in reducing transmission from community based infected persons, particularly those with symptomatic illness."

So it is accurate to say that we had reason to believe that masks work. But it is easy to overstate how much we "knew" it to be true at the time.

Re: Why is it so hard to be rational?

#120
post #14

I maintain that it isn't just hard, it is computationally impossible. We should all know that given a belief about the world, and evidence, Bayes' Theorem describes how to update our beliefs. But what if we have a network of interrelated beliefs? That's called a Bayesian net, and it turns out that Bayes' Theorem also prescribes a unique answer. However, unfortunately, it turns out that working out that answer is NP-h…

We should note the limitations of Bayes as well. I already responded to another comment in this thread that giving an update procedure based on seeing new evidence is necessarily bounded in how quickly it can get you to beliefs more likely to be true by your ability to actually gather that evidence or possibly even to generate it if it doesn't already exist. We don't have any perfect algorithms for doing that, and it is of course not a purely computational problem anyway. Take general relativity. It was proposed in 1915 and only confirmed in the very strong gravitational field limit in 2016, because that was our first opportunity to observe a black hole merger, which is not something we have the ability to recreate in a lab.

Even beyond the hard process bottleneck on creating or lucking upon events that produce the evidence we need, however, there is also the limitation that Bayes only gives you a probability. It doesn't give you a decision theory or even a thresholding function. For those, you need a whole lot of other things like utility functions, discount rates, receiver operating characteristics and an understanding of asymmetric costs of false positives versus false negatives, that are often different for each decision domain.

And, of course, to get a utility function meaningful for humans, you need values. There is no algorithm that can give you values. They're just there as a basic primitive input to all other decision making procedures, yet they often conflict in ways that cannot be reconciled even within a single person, let alone across a society of many people.

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