I think _. as an answer signals the question didn't make sense.  As _. 
is _not a number_ (it could be Lucciano Pavarotti's high C), operations 
like x + _. and x >. _. are undefined.  Another user could be depending 
on _. as a signal the operation was undefined.

Of course, depending on _. for anything can be questioned, and you can 
ask why _ , which also is not a number, gets special treatment.  The 
difference is, we know what rules _ obeys.  See for example The Extended 
Real Number System, Section 1.23 of Walter Rudin's Principles of 
Mathematical Analysis, Third Edition.

Kip Murray

On Thu, 7 Feb 2008, Henry Rich wrote:

  (Note that the subject of the original message contained
  a typo <. for >., though the text was correct.)
  
  I don't see the logic. x+_.
  is _. because if you don't know what _. is, you don't
  know the result, even if x is _  .  But with _ >. _. 
  you know the result, no matter what _. is: _ >. x
  is _ for all x.  So _ would be a reasonable answer.
  
  You said earlier that _. <: _  should produce 1,
  which seems to conform to my argument above.  If
  _. is recognized as less-or-equal _, I think it
  needs to follow that _. >. _ is _    .
  
  The case that got me into this _. mess was
  
  1 2 3 _ I. _.
  
  where I had a list that I thought I had terminated with a
  high value, but I found that _. is higher yet.  It
  would simplify analysis and description if _. were
  consistently recognized as not being bigger than _   .
  
  Henry Rich
  
  > -----Original Message-----
  > From: [EMAIL PROTECTED] 
  > [mailto:[EMAIL PROTECTED] On Behalf Of Roger Hui
  > Sent: Wednesday, February 06, 2008 10:45 PM
  > To: Beta forum
  > Subject: Re: [Jbeta] Another incompatibility: _ <. _.
  > 
  > The answer should be _. for the same reason that x+_. should be _. .
  > That is, for all numeric atoms x, _. should be the answer for
  > 
  >    x  +  _.
  >    x  >. _.
  >    x  <. _.
  >    _. +  x
  >    _. >. x
  >    _. <. x
  > 
  > 
  > 
  > ----- Original Message -----
  > From: Henry Rich <[EMAIL PROTECTED]>
  > Date: Wednesday, February 6, 2008 6:55
  > Subject: [Jbeta] Another incompatibility: _ <. _.
  > To: 'Beta forum' <[email protected]>
  > 
  > > I also just got bit by
  > > 
  > >    _ >. _.
  > > _.
  > > 
  > > This gave _ in 601.  And in 602,
  > > 
  > >    _. >. _
  > > _ 
  > > 
  > > 
  > > I think both results should be _
  > ----------------------------------------------------------------------
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  > http://www.jsoftware.com/forums.htm
  
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Kip Murray

[EMAIL PROTECTED]
http://www.math.uh.edu/~km
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