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Decomposition of Existential Quantifications

Proposition: For proving with knowledge K the goal exists x: G, it suffices to prove G[x <- T] for some term T.

exists x: G
G[x <- T]

"We have to prove (exists x: G). We prove G[x <- T]".

We have to find a witness, i.e., a value for x that makes G true.

Author: Wolfgang Schreiner
Last Modification: November 30, 1999

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