Database
CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY
Predicate calculus with equality: Auxiliary axiom schemes (4 schemes)
Axiom scheme ax-12 (Substitution)
hb3anOLD
Metamath Proof Explorer
Description: Obsolete version of hb3an as of 23-Oct-2026. (Contributed by NM , 14-Sep-2003) (Proof shortened by Wolf Lammen , 2-Jan-2018)
(Proof modification is discouraged.) (New usage is discouraged.)
Ref
Expression
Hypotheses
hbOLD.1
⊢ φ → ∀ x φ
hbOLD.2
⊢ ψ → ∀ x ψ
hbOLD.3
⊢ χ → ∀ x χ
Assertion
hb3anOLD
⊢ φ ∧ ψ ∧ χ → ∀ x φ ∧ ψ ∧ χ
Proof
Step
Hyp
Ref
Expression
1
hbOLD.1
⊢ φ → ∀ x φ
2
hbOLD.2
⊢ ψ → ∀ x ψ
3
hbOLD.3
⊢ χ → ∀ x χ
4
1
nf5i
⊢ Ⅎ x φ
5
2
nf5i
⊢ Ⅎ x ψ
6
3
nf5i
⊢ Ⅎ x χ
7
4 5 6
nf3an
⊢ Ⅎ x φ ∧ ψ ∧ χ
8
7
nf5ri
⊢ φ ∧ ψ ∧ χ → ∀ x φ ∧ ψ ∧ χ