Skip to content

Latest commit

 

History

History

semantics

Semantics, soundness, and consistency for the HOL inference system with ad-hoc overloading of constant definitions.

holBoolScript.sml: Define semantics for the Boolean operations and show the definitions are correct.

holConsistencyScript.sml: Proves consistency of the inference system: starting from any context with a model, any context reached by non-axiomatic extensions has both provable and unprovable sequents. And the base case: the HOL contexts (initial context with no axioms, with all but infinity axiom, with all three axioms) have models (under suitable assumptions).

holExtensionScript.sml: Auxiliary functions and lemmas for defining and reasoning about the model extension function.

holModelConservativityScript.sml: Proves model-theoretic conservative extension of HOL, extending a model of a theory wrt a theory update. The model extension keeps those interpretations of the smaller model, for types and constants from the so-called independent fragment. In the independent fragment are all types and constants that are not depending on what is introduced by the update.

holSemanticsExtraScript.sml: Some lemmas about the semantics.

holSemanticsScript.sml: Define semantics for HOL sequents, in particular the notion of entailment i.e. valid sequents, which are those that are satisfied by any model of the theory context.

holSoundnessScript.sml: Proves soundness of the inference system: any provable sequent is valid.