| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							ismred2.ss | 
							⊢ ( 𝜑  →  𝐶  ⊆  𝒫  𝑋 )  | 
						
						
							| 2 | 
							
								
							 | 
							ismred2.in | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶 )  →  ( 𝑋  ∩  ∩  𝑠 )  ∈  𝐶 )  | 
						
						
							| 3 | 
							
								
							 | 
							eqid | 
							⊢ ∅  =  ∅  | 
						
						
							| 4 | 
							
								
							 | 
							rint0 | 
							⊢ ( ∅  =  ∅  →  ( 𝑋  ∩  ∩  ∅ )  =  𝑋 )  | 
						
						
							| 5 | 
							
								3 4
							 | 
							ax-mp | 
							⊢ ( 𝑋  ∩  ∩  ∅ )  =  𝑋  | 
						
						
							| 6 | 
							
								
							 | 
							0ss | 
							⊢ ∅  ⊆  𝐶  | 
						
						
							| 7 | 
							
								
							 | 
							0ex | 
							⊢ ∅  ∈  V  | 
						
						
							| 8 | 
							
								
							 | 
							sseq1 | 
							⊢ ( 𝑠  =  ∅  →  ( 𝑠  ⊆  𝐶  ↔  ∅  ⊆  𝐶 ) )  | 
						
						
							| 9 | 
							
								8
							 | 
							anbi2d | 
							⊢ ( 𝑠  =  ∅  →  ( ( 𝜑  ∧  𝑠  ⊆  𝐶 )  ↔  ( 𝜑  ∧  ∅  ⊆  𝐶 ) ) )  | 
						
						
							| 10 | 
							
								
							 | 
							inteq | 
							⊢ ( 𝑠  =  ∅  →  ∩  𝑠  =  ∩  ∅ )  | 
						
						
							| 11 | 
							
								10
							 | 
							ineq2d | 
							⊢ ( 𝑠  =  ∅  →  ( 𝑋  ∩  ∩  𝑠 )  =  ( 𝑋  ∩  ∩  ∅ ) )  | 
						
						
							| 12 | 
							
								11
							 | 
							eleq1d | 
							⊢ ( 𝑠  =  ∅  →  ( ( 𝑋  ∩  ∩  𝑠 )  ∈  𝐶  ↔  ( 𝑋  ∩  ∩  ∅ )  ∈  𝐶 ) )  | 
						
						
							| 13 | 
							
								9 12
							 | 
							imbi12d | 
							⊢ ( 𝑠  =  ∅  →  ( ( ( 𝜑  ∧  𝑠  ⊆  𝐶 )  →  ( 𝑋  ∩  ∩  𝑠 )  ∈  𝐶 )  ↔  ( ( 𝜑  ∧  ∅  ⊆  𝐶 )  →  ( 𝑋  ∩  ∩  ∅ )  ∈  𝐶 ) ) )  | 
						
						
							| 14 | 
							
								7 13 2
							 | 
							vtocl | 
							⊢ ( ( 𝜑  ∧  ∅  ⊆  𝐶 )  →  ( 𝑋  ∩  ∩  ∅ )  ∈  𝐶 )  | 
						
						
							| 15 | 
							
								6 14
							 | 
							mpan2 | 
							⊢ ( 𝜑  →  ( 𝑋  ∩  ∩  ∅ )  ∈  𝐶 )  | 
						
						
							| 16 | 
							
								5 15
							 | 
							eqeltrrid | 
							⊢ ( 𝜑  →  𝑋  ∈  𝐶 )  | 
						
						
							| 17 | 
							
								
							 | 
							simp2 | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶  ∧  𝑠  ≠  ∅ )  →  𝑠  ⊆  𝐶 )  | 
						
						
							| 18 | 
							
								1
							 | 
							3ad2ant1 | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶  ∧  𝑠  ≠  ∅ )  →  𝐶  ⊆  𝒫  𝑋 )  | 
						
						
							| 19 | 
							
								17 18
							 | 
							sstrd | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶  ∧  𝑠  ≠  ∅ )  →  𝑠  ⊆  𝒫  𝑋 )  | 
						
						
							| 20 | 
							
								
							 | 
							simp3 | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶  ∧  𝑠  ≠  ∅ )  →  𝑠  ≠  ∅ )  | 
						
						
							| 21 | 
							
								
							 | 
							rintn0 | 
							⊢ ( ( 𝑠  ⊆  𝒫  𝑋  ∧  𝑠  ≠  ∅ )  →  ( 𝑋  ∩  ∩  𝑠 )  =  ∩  𝑠 )  | 
						
						
							| 22 | 
							
								19 20 21
							 | 
							syl2anc | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶  ∧  𝑠  ≠  ∅ )  →  ( 𝑋  ∩  ∩  𝑠 )  =  ∩  𝑠 )  | 
						
						
							| 23 | 
							
								2
							 | 
							3adant3 | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶  ∧  𝑠  ≠  ∅ )  →  ( 𝑋  ∩  ∩  𝑠 )  ∈  𝐶 )  | 
						
						
							| 24 | 
							
								22 23
							 | 
							eqeltrrd | 
							⊢ ( ( 𝜑  ∧  𝑠  ⊆  𝐶  ∧  𝑠  ≠  ∅ )  →  ∩  𝑠  ∈  𝐶 )  | 
						
						
							| 25 | 
							
								1 16 24
							 | 
							ismred | 
							⊢ ( 𝜑  →  𝐶  ∈  ( Moore ‘ 𝑋 ) )  |