**From:** Tom McCabe (*rocketjet314@yahoo.com*)

**Date:** Tue Aug 28 2007 - 10:15:22 MDT

**Next message:**Алексей Турчин: "Re: Re: ESSAY: How to deter a rogue AI by using your first-mover advantage"**Previous message:**Stathis Papaioannou: "Re: ESSAY: How to deter a rogue AI by using your first-mover advantage"**In reply to:**Norman Noman: "Re: Re[2]: Simulation argument in the NY Times"**Next in thread:**P K: "Simulation argument and Occam's razor"**Reply:**P K: "Simulation argument and Occam's razor"**Messages sorted by:**[ date ] [ thread ] [ subject ] [ author ] [ attachment ]

--- Norman Noman <overturnedchair@gmail.com> wrote:

*> > "Rare" covers a very large spectrum of
*

*> probabilities,
*

*> > from 10^-1 to 10^-100000000000000 (and so on). In
*

*> > order for something to qualify as a "miracle", its
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*> > probability would have to be so low that the event
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*> > provides enough Bayesian evidence to overturn our
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*> > current model. Eg, if we saw Mount Everest
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*> > spontaneously levitate several hundred meters in
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*> the
*

*> > air, this would require a new model of physics. If
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*> we
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*> > saw a large chunk of rock spontaneously break off
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*> of
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*> > Mount Everest, it would be rare, but it would not
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*> > qualify as a miracle because it wouldn't require
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*> new
*

*> > laws of physics to explain.
*

*>
*

*>
*

*> I can randomly mash keys on the keyboard for a few
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*> minutes and produce a
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*> text string with a 1 in
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*> 1000000000000000000000000000000000000000000 chance
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*> of appearing. Rareness is not the sole prerequisite
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*> for miracles.
*

"Suppose I flip a coin twenty times. If I believe the

coin is fair, the best prediction I can make is to

predict an even chance of heads or tails on each flip.

If I believe the coin is fair, I assign the same

probability to every possible sequence of twenty

coinflips. There are roughly a million (1,048,576)

possible sequences of twenty coinflips, and I have

only 1.0 of probability mass to play with. So I assign

to each individual possible sequence a probability of

(1/2)^20 - odds of about a million to one; -20 bits or

-60 decibels.

I made an experimental prediction and got a score of

-60 decibels! Doesn't this falsify the hypothesis?

Intuitively, no. We do not flip a coin twenty times

and see a random-looking result, then reel back and

say, why, the odds of that are a million to one. But

the odds are a million to one against seeing that

exact sequence, as I would discover if I naively

predicted the exact same outcome for the next sequence

of twenty coinflips. It's okay to have theories that

assign tiny probabilities to outcomes, so long as no

other theory does better. But if someone used an

alternate hypothesis to write down the exact sequence

in a sealed envelope in advance, and she assigned a

probability of 99%, I would suspect the fairness of

the coin. Provided that she only sealed one envelope,

and not a million.

That tells us what we ought common-sensically to

answer, but it doesn't say how the common-sense answer

arises from the math. To say why the common sense is

correct, we need to integrate all that has been said

so far into the framework of Bayesian revision of

belief. When we're done, we'll have a technical

understanding of the difference between a verbal

understanding and a technical understanding."

- http://www.yudkowsky.net/bayes/technical.html

*> > Conservation of mass (adjusted)
*

*> > > The mass of a closed system of substances will
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*> > > remain constant, regardless
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*> > > of the processes acting inside the system,
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*> except
*

*> > > when people are being
*

*> > > turned into frogs.
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*> > >
*

*> > > Yes, I can see how after a few years, that
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*> little
*

*> > > wrinkle would be all
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*> > > ironed out.
*

*> >
*

*> > The laws of physics as we now understand them
*

*> don't
*

*> > work like that. If we discovered a violation of
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*> CoM,
*

*> > it would probably be a violation that occurs
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*> > everywhere, but is simply too small to notice
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*> under
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*> > normal circumstances.
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*>
*

*>
*

*> Yes, that was kind of my point.
*

*>
*

- Tom

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**Next message:**Алексей Турчин: "Re: Re: ESSAY: How to deter a rogue AI by using your first-mover advantage"**Previous message:**Stathis Papaioannou: "Re: ESSAY: How to deter a rogue AI by using your first-mover advantage"**In reply to:**Norman Noman: "Re: Re[2]: Simulation argument in the NY Times"**Next in thread:**P K: "Simulation argument and Occam's razor"**Reply:**P K: "Simulation argument and Occam's razor"**Messages sorted by:**[ date ] [ thread ] [ subject ] [ author ] [ attachment ]

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