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Started out good, but I was cringing when I got to the part where he states that rationality tells people to defect in a Prisoner's Dilemma.

TimS12y110

Pardon my ignorance in asking this stupid question:

Isn't the mainstream position among decision theorists that defect is the optimal strategy in a one-shot prisoner's dilemma game? Sure, we can say something like "a TDT-agent will cooperate with another TDT-agent." But even a TDT-agent will defect if it doesn't know the identity of the counter-party. And TDT isn't completely formalized yet, right?

In short, I'm not sure of the value of snarking a popularizer of decision theory for using the word "rationality" differently than this community uses the word, particularly when our usage is (unfortunately) not the consensus definition in the relevant field.

7phonypapercut12y

I had to laugh at the little caption. "If they each behave rationally they end up doing worse."

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[Link] RSA Animate: extremely entertaining LW-relevant cartoons

23rd Jun 2012

1 min read

7

It's a brilliant idea: a lecture by a cool modern thinker, illustrated by word-by-word doodles on a whiteboard. Excellent at pulling you along the train of thought and absolutely disallowing boredom.

The lectures' content is pretty great too, although there's a definite left-wing, populist bent that's exploting today's post-crisis hot button issues (they got Zizek, for god's sake) - some might not like it. Regardless, it's all very amusing and enlightening. Been linked to before in a comment or to, but it deserves a headline.

You can start here: http://www.youtube.com/watch?v=dFs9WO2B8uI&feature=relmfu (But they're all worth watching!)

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[-]Desrtopa12y20

Started out good, but I was cringing when I got to the part where he states that rationality tells people to defect in a Prisoner's Dilemma.

Pardon my ignorance in asking this stupid question:

Isn't the mainstream position among decision theorists that defect is the optimal strategy in a one-shot prisoner's dilemma game? Sure, we can say something like "a TDT-agent will cooperate with another TDT-agent." But even a TDT-agent will defect if it doesn't know the identity of the counter-party. And TDT isn't completely formalized yet, right?

In short, I'm not sure of the value of snarking a popularizer of decision theory for using the word "rationality" differently than this community uses the word, particularly when our usage is (unfortunately) not the consensus definition in the relevant field.

Depending on the payoff scale, a TDT agent will cooperate if it believes that the other agent has some (high enough) chance of being a TDT agent. In other words, raise the sanity waterline high enough, and TDT cooperates.

TDT / superrationality will defect probabilistically given a high enough payoff for defection, even against a known-TDT agent.

In short: TDT and superrationality theories aren't as simple as some here make them out to be, and the one-shot prisoner's dilemma has hidden depths for smart players.

[-]JonathanK12y00

Of course, the rational thing to do is to convince everyone ELSE to be "superrational", and convince them that you are ALSO "superrational", and then defect if you actually play a prisoner's dilemma for sufficiently high stakes.

Eliezer has done a good job of this. Hofstadter too. Inventing the term "superrationality" for "magicalthinking" was a good move.

[-]wedrifid12y00

Depending on the payoff scale, a TDT agent will cooperate if it believes that the other agent has some (high enough) chance of being a TDT agent.

He also has to believe that the other agent believes with sufficient confidence that he is a suitable kind of agent. Same population makeup considerations apply.

[-]Desrtopa12y10

Increasing the rationality of a population can lead to that population being worse off, even by the "rationality as systematized winning" definition, if the members are at odds with each other. You don't necessarily want your adversaries to be more rational. But the reason that part made me cringe is that it carries so many caveats that it's incredibly misleading. There are many contexts where defecting in a prisoner's dilemma is a predictably bad idea, and rationality already has image problems as being rigid and unadaptable as well as antisocial without reinforcing them.

The video probably couldn't really have gone into a proper discussion of what variations of the prisoner's dilemma make defection appropriate without breaking the flow, but it really wasn't helped by a message of "paradoxically, rationality can leave you worse off."

I agree with your point that usage of rationality this way exacerbates the problem of straw-vulcanism. I'm not sure the criticism is aimed at the lowest hanging fruit in this case, but your point is well taken.

Your point about the dangerousness of rationality is not on point. I am almost strictly better off in a society in which the members are not at odds than in one where they are at odds. But whether one of the exceptions to that statement applies does not appear to depends on how dangerous individual members are. Unless individuals are so dangerous that mutually assured destruction is an important part of the analysis. And that is currently so unrealistic (at the individual level) that I don't think it is worth talking about.

[-]Desrtopa12y00

Your point about the dangerousness of rationality is not on point.

My point is not that rationality is dangerous. It's possible to formulate situations in which increasing the rationality of a population leaves the population worse off, rather like it's possible to formulate situations that reward agents for having priors that would normally be stupid. The fact that you can contrive such situations doesn't constitute a compelling criticism of rationality, which is what makes the video problematic. If rationality really were that dangerous, the implicit criticism would be entirely valid.

[-]phonypapercut12y70

I had to laugh at the little caption.

"If they each behave rationally they end up doing worse."

[-]timtyler12y180

That's what happens in Bayesian hell.

[-][anonymous]12y20

What's your prior on that?

[-]sketerpot12y170

I assure you that after you've witnessed the horrors of Bayesian Hell, only your posterior beliefs about it will matter to you.

[-]Multiheaded12y10

Hmm, looks like at least 3 people downvoted me, probably for a warning about political "bias" present in some videos. The karma loss is trivial, but I'm really perplexed by their reasoning. Because it sure looks like I wouldn't have been punished if I just pretended - in bad faith - that there's no ideology at play here, and simply shared a link!

[-]Manfred12y90

I doubt it's politics. Probably it's because they didn't like the video. There's about a third of it where he's not talking about cognitive science, he's just complaining about culture while using cognitive science words for tenuously related things.

[-]Dolores198412y00

One of the key points of restraint to insight is to avoid trying to apply them beyond their appropriate scopes.

[-]Oligopsony12y00

Zizek a populist? Really?

[-][anonymous]12y40

Uh, yes?

[-]Oligopsony12y20

I don't see how unless you're classifying "populist" as a proper subset of "left-wing," and -

Wait. I'm getting into an argument about semantics. Oops.

[-][anonymous]12y20

Eh? What does that have to do with anything? He's about the most anti-authoritarian philosopher alive, now that Derrida is dead and they de-fanged Chomsky.

[+]tenlier12y-60