| Step | Hyp | Ref | Expression | 
						
							| 1 |  | isfcls2 | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  ( 𝐴  ∈  ( 𝐽  fClus  𝐹 )  ↔  ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 ) ) ) | 
						
							| 2 |  | filn0 | ⊢ ( 𝐹  ∈  ( Fil ‘ 𝑋 )  →  𝐹  ≠  ∅ ) | 
						
							| 3 | 2 | adantl | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  𝐹  ≠  ∅ ) | 
						
							| 4 |  | r19.2z | ⊢ ( ( 𝐹  ≠  ∅  ∧  ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 ) )  →  ∃ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 ) ) | 
						
							| 5 | 4 | ex | ⊢ ( 𝐹  ≠  ∅  →  ( ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  →  ∃ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 ) ) ) | 
						
							| 6 | 3 5 | syl | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  ( ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  →  ∃ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 ) ) ) | 
						
							| 7 |  | topontop | ⊢ ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  →  𝐽  ∈  Top ) | 
						
							| 8 | 7 | ad2antrr | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝑠  ∈  𝐹 )  →  𝐽  ∈  Top ) | 
						
							| 9 |  | filelss | ⊢ ( ( 𝐹  ∈  ( Fil ‘ 𝑋 )  ∧  𝑠  ∈  𝐹 )  →  𝑠  ⊆  𝑋 ) | 
						
							| 10 | 9 | adantll | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝑠  ∈  𝐹 )  →  𝑠  ⊆  𝑋 ) | 
						
							| 11 |  | toponuni | ⊢ ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  →  𝑋  =  ∪  𝐽 ) | 
						
							| 12 | 11 | ad2antrr | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝑠  ∈  𝐹 )  →  𝑋  =  ∪  𝐽 ) | 
						
							| 13 | 10 12 | sseqtrd | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝑠  ∈  𝐹 )  →  𝑠  ⊆  ∪  𝐽 ) | 
						
							| 14 |  | eqid | ⊢ ∪  𝐽  =  ∪  𝐽 | 
						
							| 15 | 14 | clsss3 | ⊢ ( ( 𝐽  ∈  Top  ∧  𝑠  ⊆  ∪  𝐽 )  →  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ⊆  ∪  𝐽 ) | 
						
							| 16 | 8 13 15 | syl2anc | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝑠  ∈  𝐹 )  →  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ⊆  ∪  𝐽 ) | 
						
							| 17 | 16 12 | sseqtrrd | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝑠  ∈  𝐹 )  →  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ⊆  𝑋 ) | 
						
							| 18 | 17 | sseld | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝑠  ∈  𝐹 )  →  ( 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  →  𝐴  ∈  𝑋 ) ) | 
						
							| 19 | 18 | rexlimdva | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  ( ∃ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  →  𝐴  ∈  𝑋 ) ) | 
						
							| 20 | 6 19 | syld | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  ( ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  →  𝐴  ∈  𝑋 ) ) | 
						
							| 21 | 20 | pm4.71rd | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  ( ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ↔  ( 𝐴  ∈  𝑋  ∧  ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 ) ) ) ) | 
						
							| 22 | 7 | ad3antrrr | ⊢ ( ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  ∧  𝑠  ∈  𝐹 )  →  𝐽  ∈  Top ) | 
						
							| 23 | 13 | adantlr | ⊢ ( ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  ∧  𝑠  ∈  𝐹 )  →  𝑠  ⊆  ∪  𝐽 ) | 
						
							| 24 |  | simplr | ⊢ ( ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  ∧  𝑠  ∈  𝐹 )  →  𝐴  ∈  𝑋 ) | 
						
							| 25 | 11 | ad3antrrr | ⊢ ( ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  ∧  𝑠  ∈  𝐹 )  →  𝑋  =  ∪  𝐽 ) | 
						
							| 26 | 24 25 | eleqtrd | ⊢ ( ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  ∧  𝑠  ∈  𝐹 )  →  𝐴  ∈  ∪  𝐽 ) | 
						
							| 27 | 14 | elcls | ⊢ ( ( 𝐽  ∈  Top  ∧  𝑠  ⊆  ∪  𝐽  ∧  𝐴  ∈  ∪  𝐽 )  →  ( 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ↔  ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) ) | 
						
							| 28 | 22 23 26 27 | syl3anc | ⊢ ( ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  ∧  𝑠  ∈  𝐹 )  →  ( 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ↔  ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) ) | 
						
							| 29 | 28 | ralbidva | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  →  ( ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ↔  ∀ 𝑠  ∈  𝐹 ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) ) | 
						
							| 30 |  | ralcom | ⊢ ( ∀ 𝑠  ∈  𝐹 ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ )  ↔  ∀ 𝑜  ∈  𝐽 ∀ 𝑠  ∈  𝐹 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) | 
						
							| 31 |  | r19.21v | ⊢ ( ∀ 𝑠  ∈  𝐹 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ )  ↔  ( 𝐴  ∈  𝑜  →  ∀ 𝑠  ∈  𝐹 ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) | 
						
							| 32 | 31 | ralbii | ⊢ ( ∀ 𝑜  ∈  𝐽 ∀ 𝑠  ∈  𝐹 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ )  ↔  ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ∀ 𝑠  ∈  𝐹 ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) | 
						
							| 33 | 30 32 | bitri | ⊢ ( ∀ 𝑠  ∈  𝐹 ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ( 𝑜  ∩  𝑠 )  ≠  ∅ )  ↔  ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ∀ 𝑠  ∈  𝐹 ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) | 
						
							| 34 | 29 33 | bitrdi | ⊢ ( ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  ∧  𝐴  ∈  𝑋 )  →  ( ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 )  ↔  ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ∀ 𝑠  ∈  𝐹 ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) ) | 
						
							| 35 | 34 | pm5.32da | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  ( ( 𝐴  ∈  𝑋  ∧  ∀ 𝑠  ∈  𝐹 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑠 ) )  ↔  ( 𝐴  ∈  𝑋  ∧  ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ∀ 𝑠  ∈  𝐹 ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) ) ) | 
						
							| 36 | 1 21 35 | 3bitrd | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐹  ∈  ( Fil ‘ 𝑋 ) )  →  ( 𝐴  ∈  ( 𝐽  fClus  𝐹 )  ↔  ( 𝐴  ∈  𝑋  ∧  ∀ 𝑜  ∈  𝐽 ( 𝐴  ∈  𝑜  →  ∀ 𝑠  ∈  𝐹 ( 𝑜  ∩  𝑠 )  ≠  ∅ ) ) ) ) |