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Re: Every set can be ... ordered?

Subject: Re: Every set can be ... ordered?
From: The Ghost In The Machine
Date: Sat, 26 Aug 2006 06:00:06 GMT
Newsgroups: sci.logic
In sci.logic, MoeBlee
<jazzmobe@xxxxxxxxxxx>
 wrote
on 25 Aug 2006 16:39:22 -0700
<1156549162.644162.249500@xxxxxxxxxxxxxxxxxxxxxxxxxxx>:
> MoeBlee wrote:
>> And what about "every set can be partially ordered"?
>
> Oops, nevermind that question. Obviously, every set is partially
> ordered by the subset relation on the set.
>
> MoeBlee
>

Every *power* set, maybe.  But the reals wouldn't be able
to be ordered that way.

Of course it's easy enough to total order the reals;
if each real number r is defined by at least one Cauchy
sequence of rational numbers, then another real number
s can also be defined by another Cauchy sequence, and if
it is the case that there exists an M and a rational
d > 0 such that for every i,j > M, r_i > s_j + d, then r > s.

Or something like that.

Contrariwise, I am not sure if anyone's proven that one cannot
total-order a convex R^2 or R^3 subset.

-- 
#191, ewill3@xxxxxxxxxxxxx
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