Description: Introducing any antecedent in a restricted universal quantification. (Contributed by Glauco Siliprandi, 3-Mar-2021)
Ref | Expression | ||
---|---|---|---|
Assertion | ralimralim | ⊢ ( ∀ 𝑥 ∈ 𝐴 𝜑 → ∀ 𝑥 ∈ 𝐴 ( 𝜓 → 𝜑 ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nfra1 | ⊢ Ⅎ 𝑥 ∀ 𝑥 ∈ 𝐴 𝜑 | |
2 | rspa | ⊢ ( ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝜑 ) | |
3 | ax-1 | ⊢ ( 𝜑 → ( 𝜓 → 𝜑 ) ) | |
4 | 2 3 | syl | ⊢ ( ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( 𝜓 → 𝜑 ) ) |
5 | 4 | ex | ⊢ ( ∀ 𝑥 ∈ 𝐴 𝜑 → ( 𝑥 ∈ 𝐴 → ( 𝜓 → 𝜑 ) ) ) |
6 | 1 5 | ralrimi | ⊢ ( ∀ 𝑥 ∈ 𝐴 𝜑 → ∀ 𝑥 ∈ 𝐴 ( 𝜓 → 𝜑 ) ) |