What does it mean: “the closure of the axioms”?

" As we will see, the sensible axioms are so made that the sensible effects (in the semantic feeling, cf, p 56) of the closure of the axioms of $K$ are specifically the theories of $K$." Web page 60 "Introduction to Mathematical Logic" SECOND EDITION by ELLIOTT MENDELSON The very same remains in 4th version.

What does it suggest: "the closure of the axioms"?

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2022-06-07 14:34:28
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Answers: 1

Maybe: the closure of a formula suggests globally evaluating over all its free variables? And also probably this definition is someplace prior to web page 60?

Edit . Search in the index under: closure, (global) of a formula

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2022-06-07 14:53:36
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