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Re: The "two child problem"



Leigh writes:

...
Suppose that you could tell that his ace was red. What is
the probability that he has at least one more ace?

Suppose that you could tell that his ace was of hearts. What
is the probability that he has at least one more ace?
...

And suppose it *was*, indeed, the ace of hearts, but all you could
*tell* was that it was red? I guess this kind of question serves to
make the (important?) point that we are talking about something
different than the "probabilities" we encounter in quantum mechanics.
In the two child and bridge problems, the actual probabilities are
always either 1 or 0; they can't be something in between. We are
talking about *us*--not the system we are observing--when we say the
probability is 37%, or 50%, or 56%.

John
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