MHB Conditional proof for multiple quantifier

Thread starter lize
Start date Mar 7, 2016
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Conditional Multiple Proof

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To prove ((Ǝx) F(x) → (Ǝx) G(x)) using conditional proof, start with the premises: ((Ǝx) F(x) → (∀z) H(z)) and H(a) → G(b). The discussion suggests that a formal proof in logical calculus may be necessary for clarity. A reference link is provided for additional guidance on formal proofs. Understanding the relationship between existential and universal quantifiers is crucial in this context.

Mar 7, 2016

lize

Hi, I don't know how to prove ((Ǝx) F(x) →(Ǝx) (G(x)) with conditional proof from:
((Ǝx) F(x) → (∀z) H(z))
H(a) →G(b)

Thanks

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Mar 13, 2016

Evgeny.Makarov

Gold Member

MHB

What kind of proof do you have in mind? If you are talking about a formal proof in some logical calculus, then please see https://driven2services.com/staging/mh/index.php?threads/29/.

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