Closed Formulas
A closed formula, also ground formula or sentence, is a formula in which there are no free occurrences of any variable. If A is a formula of a first-order language in which the variables v1, ..., vn have free occurrences, then A preceded by v1 ... vn is a closure of A.
Read more about this topic: Well-formed Formula
Famous quotes containing the words closed and/or formulas:
“No domain of nature is quite closed to man at all times.”
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