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Decomposition of Universally Quantified Formulas

Proposition: For proving with knowledge K the goal forall x: G, it suffices to prove G[x <- a] where a is an object constant that does not appear in K and not in G.

forall x: G
G[x <- a]
(a not in K union {G})

"We prove (forall x: G). We take an arbitrary (but fixed) constant a and show G[x <- a]."

No knowledge is available about constant yet.

Author: Wolfgang Schreiner
Last Modification: November 30, 1999

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