Description: Version of nfal with an 'h' hypothesis, avoiding ax-12 . (Contributed by SN, 11-Feb-2026)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | nfalh.1 | ⊢ ( 𝜑 → ∀ 𝑥 𝜑 ) | |
| Assertion | nfalh | ⊢ Ⅎ 𝑥 ∀ 𝑦 𝜑 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nfalh.1 | ⊢ ( 𝜑 → ∀ 𝑥 𝜑 ) | |
| 2 | 1 | hbal | ⊢ ( ∀ 𝑦 𝜑 → ∀ 𝑥 ∀ 𝑦 𝜑 ) |
| 3 | 2 | nf5i | ⊢ Ⅎ 𝑥 ∀ 𝑦 𝜑 |