Database
CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY
Predicate calculus with equality: Tarski's system S2 (1 rule, 6 schemes)
Axiom scheme ax-4 (Quantified Implication)
alrimdh
Metamath Proof Explorer
Description: Deduction form of Theorem 19.21 of Margaris p. 90, see 19.21 and
19.21h . (Contributed by NM , 10-Feb-1997) (Proof shortened by Andrew Salmon , 13-May-2011)
Ref
Expression
Hypotheses
alrimdh.1
⊢ φ → ∀ x φ
alrimdh.2
⊢ ψ → ∀ x ψ
alrimdh.3
⊢ φ → ψ → χ
Assertion
alrimdh
⊢ φ → ψ → ∀ x χ
Proof
Step
Hyp
Ref
Expression
1
alrimdh.1
⊢ φ → ∀ x φ
2
alrimdh.2
⊢ ψ → ∀ x ψ
3
alrimdh.3
⊢ φ → ψ → χ
4
1 3
alimdh
⊢ φ → ∀ x ψ → ∀ x χ
5
2 4
syl5
⊢ φ → ψ → ∀ x χ