Metamath Proof Explorer


Theorem bj-alrimg

Description: The general form of the *alrim* family of theorems: if ph is substituted for ps , then the antecedent expresses a form of nonfreeness of x in ph , so the theorem means that under a nonfreeness condition in an antecedent, one can deduce from the universally quantified implication an implication where the consequent is universally quantified. Dual of bj-exlimg . (Contributed by BJ, 9-Dec-2023)

Ref Expression
Assertion bj-alrimg ( ( 𝜑 → ∀ 𝑥 𝜓 ) → ( ∀ 𝑥 ( 𝜓𝜒 ) → ( 𝜑 → ∀ 𝑥 𝜒 ) ) )

Proof

Step Hyp Ref Expression
1 sylgt ( ∀ 𝑥 ( 𝜓𝜒 ) → ( ( 𝜑 → ∀ 𝑥 𝜓 ) → ( 𝜑 → ∀ 𝑥 𝜒 ) ) )
2 1 com12 ( ( 𝜑 → ∀ 𝑥 𝜓 ) → ( ∀ 𝑥 ( 𝜓𝜒 ) → ( 𝜑 → ∀ 𝑥 𝜒 ) ) )