Metamath Proof Explorer


Theorem al2imi

Description: Inference quantifying antecedent, nested antecedent, and consequent. (Contributed by NM, 10-Jan-1993)

Ref Expression
Hypothesis al2imi.1 ( 𝜑 → ( 𝜓𝜒 ) )
Assertion al2imi ( ∀ 𝑥 𝜑 → ( ∀ 𝑥 𝜓 → ∀ 𝑥 𝜒 ) )

Proof

Step Hyp Ref Expression
1 al2imi.1 ( 𝜑 → ( 𝜓𝜒 ) )
2 al2im ( ∀ 𝑥 ( 𝜑 → ( 𝜓𝜒 ) ) → ( ∀ 𝑥 𝜑 → ( ∀ 𝑥 𝜓 → ∀ 𝑥 𝜒 ) ) )
3 2 1 mpg ( ∀ 𝑥 𝜑 → ( ∀ 𝑥 𝜓 → ∀ 𝑥 𝜒 ) )