We Want MoR – Chapter 86


Revelations on the Defense Professor and wild hypothesizing coupled with some delightfully paranoid speculation.

Next week we’ll be covering chapters 87, 88, and 89!

Original chapters, written by Eliezer Yudkowsky, can be read here and the audiobook chapters, recorded by Eneasz Brodski, can be found earlier in this podcast feed and on the website.

Album art courtesy of Lorec. Thank you!

Coy manages an RSS feed that compiles the relevant audiobook chapters with the WW MoR counterparts. Just copy and paste that link into your favorite podcast app in the “add by url” option. Thanks, Coy!

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  1. Even if Voldemort really isn’t as smart as Harry that doesn’t really explain why he didn’t take over magical Britain. It would take Fred and George less than five minutes to come up with a better way to take over the country than conventional terrorism.

    I would bet good money that most real life teenagers who read the canon version of Harry Potter cone up with at least one clever way to subvert the Ministry.

    Brian is definitely right about Harry being blinded by his own self importance.

  2. Benjamin Grunert

    Nope, Brian is absolutely wrong here. He said that Harry is trusting his math too much and that the Bayesian approach leads him astray. But it’s the opposite. Whenever he’s using Bayesian reasoning in the chapter it shifts him closer to the “It’s Voldemort.” hypothesis. When Severus says that he would understand the prophecy if it was already fulfilled, Harry doesn’t make up a probability, but just says “I don’t know what to make of that.” He even thinks “In worlds with a smart Lord Voldemort, everyone in the Order of the Phoenix died in the first five minutes of the war. The world doesn’t look like that, so we don’t live in that world. QED.” Which abandons the Bayesian approach completely.

    Using Bayes theorem is literally the optimal way to update on evidence. Even if you make up all the probabilities, if you’re trying to be moderately reasonable in the probabilities you make up you are going to slowly but surely drift towards the right answer.

    But it’s hard and if you are arguing with people it’s counterintuitive, because it’s restraining your ability to lie, which the human brain evolved to fight against.

    The point of the chapter is that Harry could have cracked it, if only he hadn’t been too proud to pull out a pen and paper and actually changed his mind according to the math.

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