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The Quotient Term Algebra

The effect of applying the equations to the term algebra is a partitioning or quotienting of the terms into equivalence classes; the equations enable us to say that certain terms which are syntactically distinct do, nevertheless, have the same meaning. (In the usual algebra of natural numbers, 2+2, 3+1,4,4*1 are all members of the equivalence class of 4). Applying the equations E above to the term algebra tex2html_wrap_inline514 , we find, for example, that the following are all members of the equivalence class of zero:

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We can regard this class as a single entity (since every member has the same semantics) and refer to it as zero. Any other term would do to represent the class; zero is simply the shortest (and most intuitively clear). Again, some members of the equivalence class of T are

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We can refer to this class as T, the representative form for the class.





Jean Baillie
Thu May 23 16:30:42 BST 1996