| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ptbas.1 | ⊢ 𝐵  =  { 𝑥  ∣  ∃ 𝑔 ( ( 𝑔  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑔 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑧  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑧 ) ( 𝑔 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑥  =  X 𝑦  ∈  𝐴 ( 𝑔 ‘ 𝑦 ) ) } | 
						
							| 2 | 1 | elpt | ⊢ ( 𝑋  ∈  𝐵  ↔  ∃ 𝑎 ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) ) ) | 
						
							| 3 | 1 | elpt | ⊢ ( 𝑌  ∈  𝐵  ↔  ∃ 𝑏 ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) ) | 
						
							| 4 | 2 3 | anbi12i | ⊢ ( ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ↔  ( ∃ 𝑎 ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) )  ∧  ∃ 𝑏 ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) ) ) | 
						
							| 5 |  | exdistrv | ⊢ ( ∃ 𝑎 ∃ 𝑏 ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) )  ∧  ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) )  ↔  ( ∃ 𝑎 ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) )  ∧  ∃ 𝑏 ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) ) ) | 
						
							| 6 | 4 5 | bitr4i | ⊢ ( ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ↔  ∃ 𝑎 ∃ 𝑏 ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) )  ∧  ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) ) ) | 
						
							| 7 |  | an4 | ⊢ ( ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) )  ∧  ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) )  ↔  ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( 𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) ) ) | 
						
							| 8 |  | an6 | ⊢ ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) )  ↔  ( ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) )  ∧  ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) ) | 
						
							| 9 |  | df-3an | ⊢ ( ( ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) )  ∧  ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) )  ↔  ( ( ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) ) | 
						
							| 10 | 8 9 | bitri | ⊢ ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) )  ↔  ( ( ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) ) | 
						
							| 11 |  | reeanv | ⊢ ( ∃ 𝑐  ∈  Fin ∃ 𝑑  ∈  Fin ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ↔  ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 12 |  | fveq2 | ⊢ ( 𝑦  =  𝑘  →  ( 𝑎 ‘ 𝑦 )  =  ( 𝑎 ‘ 𝑘 ) ) | 
						
							| 13 |  | fveq2 | ⊢ ( 𝑦  =  𝑘  →  ( 𝑏 ‘ 𝑦 )  =  ( 𝑏 ‘ 𝑘 ) ) | 
						
							| 14 | 12 13 | ineq12d | ⊢ ( 𝑦  =  𝑘  →  ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  =  ( ( 𝑎 ‘ 𝑘 )  ∩  ( 𝑏 ‘ 𝑘 ) ) ) | 
						
							| 15 | 14 | cbvixpv | ⊢ X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  =  X 𝑘  ∈  𝐴 ( ( 𝑎 ‘ 𝑘 )  ∩  ( 𝑏 ‘ 𝑘 ) ) | 
						
							| 16 |  | simpl1l | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  𝐴  ∈  𝑉 ) | 
						
							| 17 |  | unfi | ⊢ ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  →  ( 𝑐  ∪  𝑑 )  ∈  Fin ) | 
						
							| 18 | 17 | ad2antrl | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  ( 𝑐  ∪  𝑑 )  ∈  Fin ) | 
						
							| 19 |  | simpl1r | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  𝐹 : 𝐴 ⟶ Top ) | 
						
							| 20 | 19 | ffvelcdmda | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  𝐴 )  →  ( 𝐹 ‘ 𝑘 )  ∈  Top ) | 
						
							| 21 |  | simpl3l | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 22 |  | fveq2 | ⊢ ( 𝑦  =  𝑘  →  ( 𝐹 ‘ 𝑦 )  =  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 23 | 12 22 | eleq12d | ⊢ ( 𝑦  =  𝑘  →  ( ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ↔  ( 𝑎 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 ) ) ) | 
						
							| 24 | 23 | rspccva | ⊢ ( ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  𝑘  ∈  𝐴 )  →  ( 𝑎 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 25 | 21 24 | sylan | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  𝐴 )  →  ( 𝑎 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 26 |  | simpl3r | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 27 | 13 22 | eleq12d | ⊢ ( 𝑦  =  𝑘  →  ( ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ↔  ( 𝑏 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 ) ) ) | 
						
							| 28 | 27 | rspccva | ⊢ ( ( ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  𝑘  ∈  𝐴 )  →  ( 𝑏 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 29 | 26 28 | sylan | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  𝐴 )  →  ( 𝑏 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 30 |  | inopn | ⊢ ( ( ( 𝐹 ‘ 𝑘 )  ∈  Top  ∧  ( 𝑎 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 )  ∧  ( 𝑏 ‘ 𝑘 )  ∈  ( 𝐹 ‘ 𝑘 ) )  →  ( ( 𝑎 ‘ 𝑘 )  ∩  ( 𝑏 ‘ 𝑘 ) )  ∈  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 31 | 20 25 29 30 | syl3anc | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  𝐴 )  →  ( ( 𝑎 ‘ 𝑘 )  ∩  ( 𝑏 ‘ 𝑘 ) )  ∈  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 32 |  | simprrl | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 33 |  | ssun1 | ⊢ 𝑐  ⊆  ( 𝑐  ∪  𝑑 ) | 
						
							| 34 |  | sscon | ⊢ ( 𝑐  ⊆  ( 𝑐  ∪  𝑑 )  →  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) )  ⊆  ( 𝐴  ∖  𝑐 ) ) | 
						
							| 35 | 33 34 | ax-mp | ⊢ ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) )  ⊆  ( 𝐴  ∖  𝑐 ) | 
						
							| 36 | 35 | sseli | ⊢ ( 𝑘  ∈  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) )  →  𝑘  ∈  ( 𝐴  ∖  𝑐 ) ) | 
						
							| 37 | 22 | unieqd | ⊢ ( 𝑦  =  𝑘  →  ∪  ( 𝐹 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 38 | 12 37 | eqeq12d | ⊢ ( 𝑦  =  𝑘  →  ( ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ↔  ( 𝑎 ‘ 𝑘 )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) ) | 
						
							| 39 | 38 | rspccva | ⊢ ( ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  𝑘  ∈  ( 𝐴  ∖  𝑐 ) )  →  ( 𝑎 ‘ 𝑘 )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 40 | 32 36 39 | syl2an | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) ) )  →  ( 𝑎 ‘ 𝑘 )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 41 |  | simprrr | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 42 |  | ssun2 | ⊢ 𝑑  ⊆  ( 𝑐  ∪  𝑑 ) | 
						
							| 43 |  | sscon | ⊢ ( 𝑑  ⊆  ( 𝑐  ∪  𝑑 )  →  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) )  ⊆  ( 𝐴  ∖  𝑑 ) ) | 
						
							| 44 | 42 43 | ax-mp | ⊢ ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) )  ⊆  ( 𝐴  ∖  𝑑 ) | 
						
							| 45 | 44 | sseli | ⊢ ( 𝑘  ∈  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) )  →  𝑘  ∈  ( 𝐴  ∖  𝑑 ) ) | 
						
							| 46 | 13 37 | eqeq12d | ⊢ ( 𝑦  =  𝑘  →  ( ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ↔  ( 𝑏 ‘ 𝑘 )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) ) | 
						
							| 47 | 46 | rspccva | ⊢ ( ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  𝑘  ∈  ( 𝐴  ∖  𝑑 ) )  →  ( 𝑏 ‘ 𝑘 )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 48 | 41 45 47 | syl2an | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) ) )  →  ( 𝑏 ‘ 𝑘 )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 49 | 40 48 | ineq12d | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) ) )  →  ( ( 𝑎 ‘ 𝑘 )  ∩  ( 𝑏 ‘ 𝑘 ) )  =  ( ∪  ( 𝐹 ‘ 𝑘 )  ∩  ∪  ( 𝐹 ‘ 𝑘 ) ) ) | 
						
							| 50 |  | inidm | ⊢ ( ∪  ( 𝐹 ‘ 𝑘 )  ∩  ∪  ( 𝐹 ‘ 𝑘 ) )  =  ∪  ( 𝐹 ‘ 𝑘 ) | 
						
							| 51 | 49 50 | eqtrdi | ⊢ ( ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  ∧  𝑘  ∈  ( 𝐴  ∖  ( 𝑐  ∪  𝑑 ) ) )  →  ( ( 𝑎 ‘ 𝑘 )  ∩  ( 𝑏 ‘ 𝑘 ) )  =  ∪  ( 𝐹 ‘ 𝑘 ) ) | 
						
							| 52 | 1 16 18 31 51 | elptr2 | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  X 𝑘  ∈  𝐴 ( ( 𝑎 ‘ 𝑘 )  ∩  ( 𝑏 ‘ 𝑘 ) )  ∈  𝐵 ) | 
						
							| 53 | 15 52 | eqeltrid | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin )  ∧  ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) | 
						
							| 54 | 53 | expr | ⊢ ( ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( 𝑐  ∈  Fin  ∧  𝑑  ∈  Fin ) )  →  ( ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  →  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) ) | 
						
							| 55 | 54 | rexlimdvva | ⊢ ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  →  ( ∃ 𝑐  ∈  Fin ∃ 𝑑  ∈  Fin ( ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  →  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) ) | 
						
							| 56 | 11 55 | biimtrrid | ⊢ ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  →  ( ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  →  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) ) | 
						
							| 57 | 56 | 3expb | ⊢ ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) ) )  →  ( ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  →  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) ) | 
						
							| 58 | 57 | impr | ⊢ ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( ( ( 𝑎  Fn  𝐴  ∧  𝑏  Fn  𝐴 )  ∧  ( ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) | 
						
							| 59 | 10 58 | sylan2b | ⊢ ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) | 
						
							| 60 |  | ineq12 | ⊢ ( ( 𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) )  →  ( 𝑋  ∩  𝑌 )  =  ( X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∩  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) ) | 
						
							| 61 |  | ixpin | ⊢ X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  =  ( X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∩  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) | 
						
							| 62 | 60 61 | eqtr4di | ⊢ ( ( 𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) )  →  ( 𝑋  ∩  𝑌 )  =  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) ) ) | 
						
							| 63 | 62 | eleq1d | ⊢ ( ( 𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) )  →  ( ( 𝑋  ∩  𝑌 )  ∈  𝐵  ↔  X 𝑦  ∈  𝐴 ( ( 𝑎 ‘ 𝑦 )  ∩  ( 𝑏 ‘ 𝑦 ) )  ∈  𝐵 ) ) | 
						
							| 64 | 59 63 | syl5ibrcom | ⊢ ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) ) )  →  ( ( 𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) )  →  ( 𝑋  ∩  𝑌 )  ∈  𝐵 ) ) | 
						
							| 65 | 64 | expimpd | ⊢ ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  →  ( ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) ) )  ∧  ( 𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) )  →  ( 𝑋  ∩  𝑌 )  ∈  𝐵 ) ) | 
						
							| 66 | 7 65 | biimtrid | ⊢ ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  →  ( ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) )  ∧  ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) )  →  ( 𝑋  ∩  𝑌 )  ∈  𝐵 ) ) | 
						
							| 67 | 66 | exlimdvv | ⊢ ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  →  ( ∃ 𝑎 ∃ 𝑏 ( ( ( 𝑎  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑐  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑐 ) ( 𝑎 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑋  =  X 𝑦  ∈  𝐴 ( 𝑎 ‘ 𝑦 ) )  ∧  ( ( 𝑏  Fn  𝐴  ∧  ∀ 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 )  ∈  ( 𝐹 ‘ 𝑦 )  ∧  ∃ 𝑑  ∈  Fin ∀ 𝑦  ∈  ( 𝐴  ∖  𝑑 ) ( 𝑏 ‘ 𝑦 )  =  ∪  ( 𝐹 ‘ 𝑦 ) )  ∧  𝑌  =  X 𝑦  ∈  𝐴 ( 𝑏 ‘ 𝑦 ) ) )  →  ( 𝑋  ∩  𝑌 )  ∈  𝐵 ) ) | 
						
							| 68 | 6 67 | biimtrid | ⊢ ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  →  ( ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  →  ( 𝑋  ∩  𝑌 )  ∈  𝐵 ) ) | 
						
							| 69 | 68 | imp | ⊢ ( ( ( 𝐴  ∈  𝑉  ∧  𝐹 : 𝐴 ⟶ Top )  ∧  ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  ( 𝑋  ∩  𝑌 )  ∈  𝐵 ) |