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Providing a semantics for CML

The semantics of a set of CML top level forms is provided by translating them into first order logic such as defined in KIF. CML inherits the logic's model-theoretic semantics. Fully formalizing CML requires two steps:

  1. Provide a translation from each top level form into a set of axioms.
  2. Provide a set of relations, definitions, and axioms for the underlying objects employed by CML.
Section gif, page gif, defines the translation from each top level form into logic. This is done by defining the syntax of each form and then providing an axiom schema that maps the syntax into a set of axioms.

The underlying objects are only partially formalized. For instance, Section gif, page gif provides a specification of quantities, dimensions, and units. Other aspects, such as arithmetic or standard theorems of calculus and mathematics, are not axiomatized. All models of a CML theory must satisfy such background theorems and all implementations are assumed to respect them as well.

There are some difficulties associated with the use of composable equations (See section gif, page gif). These require a closed world assumption, which in turn requires CML to be defined in terms of a non-monotonic logic. This does not change the axiomatization, but rather affects the underlying semantics, as non-monotonic logics do not have a standard Tarskian model theory.



Tom Mostek
Wed Jan 21 13:00:43 CST 1998