| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							h1did | 
							 |-  ( A e. ~H -> A e. ( _|_ ` ( _|_ ` { A } ) ) ) | 
						
						
							| 2 | 
							
								
							 | 
							eleq2 | 
							 |-  ( ( _|_ ` ( _|_ ` { A } ) ) = 0H -> ( A e. ( _|_ ` ( _|_ ` { A } ) ) <-> A e. 0H ) ) | 
						
						
							| 3 | 
							
								1 2
							 | 
							syl5ibcom | 
							 |-  ( A e. ~H -> ( ( _|_ ` ( _|_ ` { A } ) ) = 0H -> A e. 0H ) ) | 
						
						
							| 4 | 
							
								
							 | 
							elch0 | 
							 |-  ( A e. 0H <-> A = 0h )  | 
						
						
							| 5 | 
							
								3 4
							 | 
							imbitrdi | 
							 |-  ( A e. ~H -> ( ( _|_ ` ( _|_ ` { A } ) ) = 0H -> A = 0h ) ) | 
						
						
							| 6 | 
							
								5
							 | 
							necon3d | 
							 |-  ( A e. ~H -> ( A =/= 0h -> ( _|_ ` ( _|_ ` { A } ) ) =/= 0H ) ) | 
						
						
							| 7 | 
							
								6
							 | 
							imp | 
							 |-  ( ( A e. ~H /\ A =/= 0h ) -> ( _|_ ` ( _|_ ` { A } ) ) =/= 0H ) |