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Date: Tue, 2 Mar 93 11:14:23 +0100
From: blok@nl.utwente.cs (Rintcius Blok)
Message-Id: <9303021014.AA00306@apollo.cs.utwente.nl>
To: info-hol@edu.uidaho.cs.ted
Subject: pair proof

Hello,

I have a problem with proving the following goal:

g "!P.(!(x:*) (y:**).x IN X /\ y IN Y==>P(x,y))=
      (!z.(FST z) IN X /\ (SND z) IN Y ==>P z)";;

I think the proof is not difficult and can be very short, 
but I cannot find/derive an appropriate theorem to "jump" from 
the first pair repr. to the second.

Is there anyone who can help? 

thanks, 
Rintcius Blok.