| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							choccl | 
							⊢ ( 𝐴  ∈   Cℋ   →  ( ⊥ ‘ 𝐴 )  ∈   Cℋ  )  | 
						
						
							| 2 | 
							
								
							 | 
							chpsscon3 | 
							⊢ ( ( ( ⊥ ‘ 𝐴 )  ∈   Cℋ   ∧  𝐵  ∈   Cℋ  )  →  ( ( ⊥ ‘ 𝐴 )  ⊊  𝐵  ↔  ( ⊥ ‘ 𝐵 )  ⊊  ( ⊥ ‘ ( ⊥ ‘ 𝐴 ) ) ) )  | 
						
						
							| 3 | 
							
								1 2
							 | 
							sylan | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝐵  ∈   Cℋ  )  →  ( ( ⊥ ‘ 𝐴 )  ⊊  𝐵  ↔  ( ⊥ ‘ 𝐵 )  ⊊  ( ⊥ ‘ ( ⊥ ‘ 𝐴 ) ) ) )  | 
						
						
							| 4 | 
							
								
							 | 
							ococ | 
							⊢ ( 𝐴  ∈   Cℋ   →  ( ⊥ ‘ ( ⊥ ‘ 𝐴 ) )  =  𝐴 )  | 
						
						
							| 5 | 
							
								4
							 | 
							adantr | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝐵  ∈   Cℋ  )  →  ( ⊥ ‘ ( ⊥ ‘ 𝐴 ) )  =  𝐴 )  | 
						
						
							| 6 | 
							
								5
							 | 
							psseq2d | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝐵  ∈   Cℋ  )  →  ( ( ⊥ ‘ 𝐵 )  ⊊  ( ⊥ ‘ ( ⊥ ‘ 𝐴 ) )  ↔  ( ⊥ ‘ 𝐵 )  ⊊  𝐴 ) )  | 
						
						
							| 7 | 
							
								3 6
							 | 
							bitrd | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝐵  ∈   Cℋ  )  →  ( ( ⊥ ‘ 𝐴 )  ⊊  𝐵  ↔  ( ⊥ ‘ 𝐵 )  ⊊  𝐴 ) )  |