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 ) |