Description: A more general instance of hbex . (Contributed by BJ, 4-Apr-2026)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | bj-hbex.1 | ⊢ ( 𝜑 → ∀ 𝑥 𝜓 ) | |
| Assertion | bj-hbex | ⊢ ( ∃ 𝑦 𝜑 → ∀ 𝑥 ∃ 𝑦 𝜓 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | bj-hbex.1 | ⊢ ( 𝜑 → ∀ 𝑥 𝜓 ) | |
| 2 | 19.12 | ⊢ ( ∃ 𝑦 ∀ 𝑥 𝜓 → ∀ 𝑥 ∃ 𝑦 𝜓 ) | |
| 3 | 2 1 | bj-sylge | ⊢ ( ∃ 𝑦 𝜑 → ∀ 𝑥 ∃ 𝑦 𝜓 ) |