# Re: MATH: Weird probability arguments

Eliezer Yudkowsky (sentience@pobox.com)
Thu, 05 Dec 1996 21:53:54 -0600

> I'm not sure about the dice. Every instinct says that the probability
> is always 1/36, but I haven't figured out how to refute the 90% argument
> in the past couple of minutes.

I think I've got it. The argument that says: "90% of the people will
see double-sixes" occurs AFTER the experiment terminates. If such an
experiment has been performed and you are told that you will be assigned
to some post-hoc group at random, odds are 90% that you will see double
sixes and you should bet that way.

If you're walking into the room and the dice are just being rolled,
chances are 1 in 36 that two sixes show. There isn't a pool of victims
to be randomly picked from yet.

Or so I see it...

```--
sentience@pobox.com      Eliezer S. Yudkowsky
http://tezcat.com/~eliezer/singularity.html
http://tezcat.com/~eliezer/algernon.html
Disclaimer:  Unless otherwise specified, I'm not telling you
everything I know.
```