Description: An instance of hbn1w applied to equality. (Contributed by Wolf Lammen, 7-Apr-2021)
Ref | Expression | ||
---|---|---|---|
Assertion | wl-naevhba1v | ⊢ ( ¬ ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑥 ¬ ∀ 𝑥 𝑥 = 𝑦 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | equequ1 | ⊢ ( 𝑥 = 𝑧 → ( 𝑥 = 𝑦 ↔ 𝑧 = 𝑦 ) ) | |
2 | 1 | hbn1w | ⊢ ( ¬ ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑥 ¬ ∀ 𝑥 𝑥 = 𝑦 ) |