Peano Algebra's are based on the following: If a unary predicate P holds for 0, and if P holds, together with an element x, also for it's succesor x', then P holds for all natural numbers. The question under consideration is NOT an attempt to describe a language in a Sigma structure/algebra/model. We are NOT trying to analyze the language but rather a specific mathematical statement made IN that language. They are not the same problem and hence Peano Algebra's do NOT apply. Nice straw man, I had to drag a math book out to refresh what a Peano Algebra was (don't think I've ever had to deal with one). ____________________________________________________________________ The seeker is a finder. Ancient Persian Proverb The Armadillo Group ,::////;::-. James Choate Austin, Tx /:'///// ``::>/|/ ravage@ssz.com www.ssz.com .', |||| `/( e\ 512-451-7087 -====~~mm-'`-```-mm --'- --------------------------------------------------------------------