| Step | Hyp | Ref | Expression | 
						
							| 1 |  | eqid | ⊢ ∪  𝐽  =  ∪  𝐽 | 
						
							| 2 | 1 | flimfil | ⊢ ( 𝑥  ∈  ( 𝐽  fLim  𝐹 )  →  𝐹  ∈  ( Fil ‘ ∪  𝐽 ) ) | 
						
							| 3 | 2 | ad2antlr | ⊢ ( ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  ∧  𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) )  →  𝐹  ∈  ( Fil ‘ ∪  𝐽 ) ) | 
						
							| 4 |  | flimnei | ⊢ ( ( 𝑥  ∈  ( 𝐽  fLim  𝐹 )  ∧  𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) )  →  𝑦  ∈  𝐹 ) | 
						
							| 5 | 4 | adantll | ⊢ ( ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  ∧  𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) )  →  𝑦  ∈  𝐹 ) | 
						
							| 6 |  | simpll | ⊢ ( ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  ∧  𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) )  →  𝑆  ∈  𝐹 ) | 
						
							| 7 |  | filinn0 | ⊢ ( ( 𝐹  ∈  ( Fil ‘ ∪  𝐽 )  ∧  𝑦  ∈  𝐹  ∧  𝑆  ∈  𝐹 )  →  ( 𝑦  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 8 | 3 5 6 7 | syl3anc | ⊢ ( ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  ∧  𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) )  →  ( 𝑦  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 9 | 8 | ralrimiva | ⊢ ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  →  ∀ 𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) ( 𝑦  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 10 |  | flimtop | ⊢ ( 𝑥  ∈  ( 𝐽  fLim  𝐹 )  →  𝐽  ∈  Top ) | 
						
							| 11 | 10 | adantl | ⊢ ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  →  𝐽  ∈  Top ) | 
						
							| 12 |  | filelss | ⊢ ( ( 𝐹  ∈  ( Fil ‘ ∪  𝐽 )  ∧  𝑆  ∈  𝐹 )  →  𝑆  ⊆  ∪  𝐽 ) | 
						
							| 13 | 12 | ancoms | ⊢ ( ( 𝑆  ∈  𝐹  ∧  𝐹  ∈  ( Fil ‘ ∪  𝐽 ) )  →  𝑆  ⊆  ∪  𝐽 ) | 
						
							| 14 | 2 13 | sylan2 | ⊢ ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  →  𝑆  ⊆  ∪  𝐽 ) | 
						
							| 15 | 1 | flimelbas | ⊢ ( 𝑥  ∈  ( 𝐽  fLim  𝐹 )  →  𝑥  ∈  ∪  𝐽 ) | 
						
							| 16 | 15 | adantl | ⊢ ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  →  𝑥  ∈  ∪  𝐽 ) | 
						
							| 17 | 1 | neindisj2 | ⊢ ( ( 𝐽  ∈  Top  ∧  𝑆  ⊆  ∪  𝐽  ∧  𝑥  ∈  ∪  𝐽 )  →  ( 𝑥  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 )  ↔  ∀ 𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) ( 𝑦  ∩  𝑆 )  ≠  ∅ ) ) | 
						
							| 18 | 11 14 16 17 | syl3anc | ⊢ ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  →  ( 𝑥  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 )  ↔  ∀ 𝑦  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) ( 𝑦  ∩  𝑆 )  ≠  ∅ ) ) | 
						
							| 19 | 9 18 | mpbird | ⊢ ( ( 𝑆  ∈  𝐹  ∧  𝑥  ∈  ( 𝐽  fLim  𝐹 ) )  →  𝑥  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) ) | 
						
							| 20 | 19 | ex | ⊢ ( 𝑆  ∈  𝐹  →  ( 𝑥  ∈  ( 𝐽  fLim  𝐹 )  →  𝑥  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) ) ) | 
						
							| 21 | 20 | ssrdv | ⊢ ( 𝑆  ∈  𝐹  →  ( 𝐽  fLim  𝐹 )  ⊆  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) ) |