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Comment author: dxu 26 November 2014 02:08:14AM *  1 point [-]

Well, the insanity defense is always a possibility, but then again, you have no proof that you're not insane right now, either, so it seems to be a fully general counterargument that can apply at any time to any situation. Ignoring the possibility of insanity, would you see any point in refusing to update, i.e. claiming that what you just saw didn't happen?

Comment author: faul_sname 26 November 2014 04:43:34AM *  2 points [-]

It's always a possibility that I'm insane, but normally a fairly unlikely one.

The baseline hypothesis is (say) p = 0.999 that I'm sane, p = 0.0001 that I'm hallucinating. Let's further assume that if I'm hallucinating, there's a 2% chance that hallucination is about time travel. My prior is something like p = 0.000001 that time travel exists. If I assume those are the only two explanations of seeing a time traveler, (i.e. we're ignoring pranks and similar), my estimate of the probability that time travel exists would shift up to about 2% instead of 0.0001% -- a huge increase. The smart money (98%) is still on me hallucinating though.

If you screen out the insanity possibility, and any other possibility that gives better than 1 in a million chances of me seeing what appears to be a time traveler with what appears to be futuristic technology, yes, the time traveler hypothesis would dominate. However, the prior for that is quite low. There's a difference between "refusing to update" and "not updating far enough that one explanation is favored".

If I was abducted by aliens, my first inclination would likewise be to assume that I'm going insane -- this is despite the fact that nothing in the laws of physics precludes the existence of aliens. Are you saying that the average person who thinks they are abducted by aliens should trust their senses on that matter?

Comment author: dxu 23 November 2014 04:35:07PM *  1 point [-]

I don't think the quote is talking about "hypothesizing" anything; I read it more as "You have to update on evidence whether that evidence fits into your original model of the world or not". Instead of "hypothesizing time travel when things don't make sense", it'd be more like a stranger appears in front of you in a flash of light with futuristic-looking technology, proves that he is genetically human, and claims to be from the future. In that case it doesn't matter what your priors were for something like that happening; it already happened, and crying "Impossible!" is as illegal a move in Bayes as moving your king into check is in chess.

Not that such a thing is likely to happen, of course, but if it did happen, would you sit back and claim it didn't because it "doesn't make sense"?

Comment author: faul_sname 25 November 2014 08:47:59PM 2 points [-]

Yes. And then I would go see a psychologist. Because I find it more likely that I'm losing my grip on my own sanity than that I've just witnessed time travel.

Comment author: Lumifer 25 November 2014 07:52:34PM 0 points [-]

Then I'm not sure what your terminal values are beyond surviving.

Comment author: faul_sname 25 November 2014 08:37:14PM *  1 point [-]

I think there may be a communication failure here. While most desirable changes are themselves changes to the status quo, the phrase "changing the status quo" generally has the connotation of moving away from an undesirable state, instead of moving toward a desirable state.

For a concrete example, if I wanted to eradicate malaria, I would say "I want to eradicate malaria," not "I want to impact the status quo" or "I want to make a difference," even though both types of statements are true. The goal is to make a specific difference, not to make a difference.

Comment author: Lumifer 19 November 2014 02:25:58AM 1 point [-]

What's so great about impacting the status quo?

Depends on your value system, of course. But impacting the status quo is a synonym for "making a difference" and if you don't ever make a difference, well...

Comment author: faul_sname 25 November 2014 07:27:20PM 0 points [-]


Please continue. If you don't ever make a difference, then what?

Comment author: Sysice 24 November 2014 11:13:05AM 2 points [-]

This isn't necessarily- if you have to think about using that link as charity while shopping, it could decrease your likelihood of doing other charitable things (which is why you should set up a redirect so you don't have to think about it, and you always use it every time!)

Comment author: faul_sname 24 November 2014 07:16:15PM 1 point [-]

Amazon already does that for you -- if you go to buy something without using that link, it'll ask you if you want to.

Comment author: Lumifer 27 October 2014 07:43:08PM *  2 points [-]

I don't see how being a writer in Nazi Germany would be any worse than being a writer anywhere else

The key word is "successful".

To become a successful romance writer in Nazi Germany would probably require you pay careful attention to certain things. For example, making sure no one who could be construed to be a Jew is ever a hero in your novels. Likely you will have to have a public position on the racial purity of marriages. Would a nice Aryan Fräulein ever be able to find happiness with a non-Aryan?

You can't become successful in a dirty society while staying spotlessly clean.

Comment author: faul_sname 27 October 2014 07:48:47PM 3 points [-]

So? Who said my goal was to stay spotlessly clean? I think more highly of Bill Gates than of Richard Stallman, because as much as Gates was a ruthless and sometimes dishonest businessman, and as much as Stallman does stick to his principles, Gates, overall, has probably improved the human condition far more than Stallman.

Comment author: Lumifer 27 October 2014 06:23:05PM *  3 points [-]

what's morally problematic about wanting to be a more successful writer or researcher or therapist?

The issue is blanket moral condemnation of the whole society. Would you want to become a "more successful writer" in Nazi Germany?

The simple step of a courageous individual is not to take part in the lie." -- Alexander Solzhenitsyn

Comment author: faul_sname 27 October 2014 07:28:57PM *  2 points [-]

The issue is blanket moral condemnation of the whole society. Would you want to become a "more successful writer" in Nazi Germany?

...yes? I wouldn't want to write Nazi propaganda, but if I was a romance novel writer and my writing would not significantly affect, for example, the Nazi war effort, I don't see how being a writer in Nazi Germany would be any worse than being a writer anywhere else. In this context, "the lie" of Nazi Germany was not the mere existence of the society, it was specific things people within that society were doing. Romance novels, even very good romance novels, are not a part of that lie by reasonable definitions.

ETA: There are certainly better things a person in Nazi Germany could do than writing romance novels. If you accept the mindset that anything that isn't optimally good is bad, then yes, being a writer in Nazi Germany is probably bad. But in that event, moving to Sweden and continuing to write romance novels is no better.

Comment author: Lumifer 04 August 2014 07:24:49PM 11 points [-]

Why is this so?

Because the case where you are entirely wedded to a particular conclusion and want to just ignore the contrary evidence would look awfully similar...

Comment author: faul_sname 07 August 2014 07:05:28AM 0 points [-]

Awfully similar, but not identical.

In the first case, you have independent evidence that the conclusion is false, so you're basically saying "If I considered your arguments in isolation, I would be convinced of your conclusion, but here are several pieces of external evidence which contradict your conclusion. I trust this external evidence more than I trust my ability to evaluate arguments."

In the second case, you're saying "I have already concluded that your conclusion is false because I have concluded that mine is true. I think it's more likely that there is a flaw in your conclusion that I can't detect than that there is a flaw in the reasoning that led to my conclusion."

The person in the first case is far more likely to respond with "I don't know" in response to the question of "So what do you think the real answer is, then?" In our culture (both outside, and, to a lesser but still significant degree inside LW), there is a stigma against arguing against a hypothesis without providing an alternative hypothesis. An exception is the argument of the form "If Y is true, how do you explain X?" which is quite common. Unfortunately, this form of argument is used extensively by people who are, as you say, entirely wedded to a particular conclusion, so using it makes you seem like one of those people and therefore less credible, especially in the eyes of LWers.

Rereading your comment, I see that there are two ways to interpret it. The first is "Rationalists do not use this form of argument because it makes them look like people who are wedded to a particular conclusion." The second is "Rationalists do not use this form of argument because it is flawed -- they see that anyone who is wedded to a particular conclusion can use it to avoid updating on evidence." I agree with the first interpretation, but not the second -- that form of argument can be valid, but reduces the credibility of the person using it in the eyes of other rationalists.

Comment author: philh 02 August 2014 11:02:05AM 3 points [-]

Oh! You're also running your opponent playing a game against MirrorBot, not against TrollBot.

Which I still don't understand... you run SMB versus MB, time limit 10000. SMB runs MB versus MB, time limit 10000. MB versus MB times out, which meas SMB runs for > 10000 us, which means that SMB should time out and you should cooperate.

Meanwhile, SMB runs you versus MB, time limit 10000. You run MB versus MB, time limit 10000. That times out, so you time out, so SMB cooperates.

But you're defecting, which means that you're running SMB versus MB to completion, which seems like it shouldn't happen.

Comment author: faul_sname 04 August 2014 12:37:16AM 1 point [-]

That does seem exploitable, if one can figure out exactly what's happening here.

Comment author: philh 01 August 2014 09:23:34PM 3 points [-]

Limit my opponent to 10ms, defect if they go over.

You actually cooperate in this case.

Quick analysis: you're going to defeat CooperateBot 500 points), lose against DefectBot (0 points), and tie against TitForTatBot (250 points from alternating D/C and C/D). Against RandomBot, you are also RandomBot, both of you scoring 225 on average.

When you simulate MirrorBot, the infinite recursion makes ver time out, so you cooperate. So MirrorBot cooperates against you as well (300 points). SmarterMirrorBot and JusticeBot both time out as well. SmarterMirrorBot can't work out what you'll do, and cooperates (300 points). JusticeBot may or may not be able to work out what you'll do against CooperateBot, and defects either way (0 points).

But I think TitForTatBot should beat that, at least: 300 against CooperateBot, 99 against DefectBot, 300 against JusticeBot, 223.5 against RandomBot, and all other scores the same.

So, I'm puzzled too, if TrollBot is getting the highest score in the first round.

Comment author: faul_sname 02 August 2014 12:31:37AM *  5 points [-]

Limit my opponent to 10ms, defect if they go over.

You actually cooperate in this case.

Whoops. Effect goes away if I fix it, too.

Here are the average results for the first round:


For some reason, TrollBot always wins 500 / 0 against SmarterMirrorBot. DefectBot actually beats TrollBot by a narrow margin (1604 - 1575 = 29 points) on average, but there is quite a bit of randomness from RandomBot, so TrollBot often comes out ahead of even DefectBot, and they both come out over 100 points ahead of the next bot (TitForTatBot).

Since I built TrollBot as a sanity check on my actual bot to make sure that it would defect against TrollBot, I was definitely surprised by the fact that TrollBot outperformed not only my attempt at a serious bot, but also most of the other bots... :/

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