Description: A normal space is a topological space. (Contributed by Jeff Hankins, 1-Feb-2010)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | nrmtop | ⊢ ( 𝐽 ∈ Nrm → 𝐽 ∈ Top ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | isnrm | ⊢ ( 𝐽 ∈ Nrm ↔ ( 𝐽 ∈ Top ∧ ∀ 𝑥 ∈ 𝐽 ∀ 𝑦 ∈ ( ( Clsd ‘ 𝐽 ) ∩ 𝒫 𝑥 ) ∃ 𝑧 ∈ 𝐽 ( 𝑦 ⊆ 𝑧 ∧ ( ( cls ‘ 𝐽 ) ‘ 𝑧 ) ⊆ 𝑥 ) ) ) | |
| 2 | 1 | simplbi | ⊢ ( 𝐽 ∈ Nrm → 𝐽 ∈ Top ) |