| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							elat2 | 
							⊢ ( 𝐴  ∈  HAtoms  ↔  ( 𝐴  ∈   Cℋ   ∧  ( 𝐴  ≠  0ℋ  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) ) )  | 
						
						
							| 2 | 
							
								
							 | 
							chne0 | 
							⊢ ( 𝐴  ∈   Cℋ   →  ( 𝐴  ≠  0ℋ  ↔  ∃ 𝑥  ∈  𝐴 𝑥  ≠  0ℎ ) )  | 
						
						
							| 3 | 
							
								
							 | 
							nfv | 
							⊢ Ⅎ 𝑥 𝐴  ∈   Cℋ   | 
						
						
							| 4 | 
							
								
							 | 
							nfv | 
							⊢ Ⅎ 𝑥 ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  | 
						
						
							| 5 | 
							
								
							 | 
							nfre1 | 
							⊢ Ⅎ 𝑥 ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) )  | 
						
						
							| 6 | 
							
								4 5
							 | 
							nfim | 
							⊢ Ⅎ 𝑥 ( ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 7 | 
							
								
							 | 
							chel | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝑥  ∈  𝐴 )  →  𝑥  ∈   ℋ )  | 
						
						
							| 8 | 
							
								7
							 | 
							adantrr | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ ) )  →  𝑥  ∈   ℋ )  | 
						
						
							| 9 | 
							
								8
							 | 
							adantrr | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  𝑥  ∈   ℋ )  | 
						
						
							| 10 | 
							
								
							 | 
							simprlr | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  𝑥  ≠  0ℎ )  | 
						
						
							| 11 | 
							
								
							 | 
							h1dn0 | 
							⊢ ( ( 𝑥  ∈   ℋ  ∧  𝑥  ≠  0ℎ )  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ≠  0ℋ )  | 
						
						
							| 12 | 
							
								7 11
							 | 
							sylan | 
							⊢ ( ( ( 𝐴  ∈   Cℋ   ∧  𝑥  ∈  𝐴 )  ∧  𝑥  ≠  0ℎ )  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ≠  0ℋ )  | 
						
						
							| 13 | 
							
								12
							 | 
							anasss | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ ) )  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ≠  0ℋ )  | 
						
						
							| 14 | 
							
								13
							 | 
							adantrr | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ≠  0ℋ )  | 
						
						
							| 15 | 
							
								
							 | 
							ch1dle | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝑥  ∈  𝐴 )  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ⊆  𝐴 )  | 
						
						
							| 16 | 
							
								
							 | 
							snssi | 
							⊢ ( 𝑥  ∈   ℋ  →  { 𝑥 }  ⊆   ℋ )  | 
						
						
							| 17 | 
							
								
							 | 
							occl | 
							⊢ ( { 𝑥 }  ⊆   ℋ  →  ( ⊥ ‘ { 𝑥 } )  ∈   Cℋ  )  | 
						
						
							| 18 | 
							
								7 16 17
							 | 
							3syl | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝑥  ∈  𝐴 )  →  ( ⊥ ‘ { 𝑥 } )  ∈   Cℋ  )  | 
						
						
							| 19 | 
							
								
							 | 
							choccl | 
							⊢ ( ( ⊥ ‘ { 𝑥 } )  ∈   Cℋ   →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ∈   Cℋ  )  | 
						
						
							| 20 | 
							
								
							 | 
							sseq1 | 
							⊢ ( 𝑦  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  ( 𝑦  ⊆  𝐴  ↔  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ⊆  𝐴 ) )  | 
						
						
							| 21 | 
							
								
							 | 
							eqeq1 | 
							⊢ ( 𝑦  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  ( 𝑦  =  𝐴  ↔  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴 ) )  | 
						
						
							| 22 | 
							
								
							 | 
							eqeq1 | 
							⊢ ( 𝑦  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  ( 𝑦  =  0ℋ  ↔  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) )  | 
						
						
							| 23 | 
							
								21 22
							 | 
							orbi12d | 
							⊢ ( 𝑦  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  ( ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ )  ↔  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  ∨  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) ) )  | 
						
						
							| 24 | 
							
								20 23
							 | 
							imbi12d | 
							⊢ ( 𝑦  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  ( ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  ↔  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ⊆  𝐴  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  ∨  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) ) ) )  | 
						
						
							| 25 | 
							
								24
							 | 
							rspcv | 
							⊢ ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ∈   Cℋ   →  ( ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ⊆  𝐴  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  ∨  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) ) ) )  | 
						
						
							| 26 | 
							
								18 19 25
							 | 
							3syl | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝑥  ∈  𝐴 )  →  ( ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ⊆  𝐴  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  ∨  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) ) ) )  | 
						
						
							| 27 | 
							
								15 26
							 | 
							mpid | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝑥  ∈  𝐴 )  →  ( ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  ∨  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) ) )  | 
						
						
							| 28 | 
							
								27
							 | 
							impr | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( 𝑥  ∈  𝐴  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  ∨  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) )  | 
						
						
							| 29 | 
							
								28
							 | 
							adantrlr | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ( ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  ∨  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) )  | 
						
						
							| 30 | 
							
								29
							 | 
							ord | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ( ¬  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ ) )  | 
						
						
							| 31 | 
							
								
							 | 
							nne | 
							⊢ ( ¬  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ≠  0ℋ  ↔  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  0ℋ )  | 
						
						
							| 32 | 
							
								30 31
							 | 
							imbitrrdi | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ( ¬  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴  →  ¬  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ≠  0ℋ ) )  | 
						
						
							| 33 | 
							
								14 32
							 | 
							mt4d | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  =  𝐴 )  | 
						
						
							| 34 | 
							
								33
							 | 
							eqcomd | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) )  | 
						
						
							| 35 | 
							
								
							 | 
							rspe | 
							⊢ ( ( 𝑥  ∈   ℋ  ∧  ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 36 | 
							
								9 10 34 35
							 | 
							syl12anc | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑥  ≠  0ℎ )  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 37 | 
							
								36
							 | 
							exp44 | 
							⊢ ( 𝐴  ∈   Cℋ   →  ( 𝑥  ∈  𝐴  →  ( 𝑥  ≠  0ℎ  →  ( ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) ) ) ) )  | 
						
						
							| 38 | 
							
								3 6 37
							 | 
							rexlimd | 
							⊢ ( 𝐴  ∈   Cℋ   →  ( ∃ 𝑥  ∈  𝐴 𝑥  ≠  0ℎ  →  ( ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) ) ) )  | 
						
						
							| 39 | 
							
								2 38
							 | 
							sylbid | 
							⊢ ( 𝐴  ∈   Cℋ   →  ( 𝐴  ≠  0ℋ  →  ( ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) )  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) ) ) )  | 
						
						
							| 40 | 
							
								39
							 | 
							imp32 | 
							⊢ ( ( 𝐴  ∈   Cℋ   ∧  ( 𝐴  ≠  0ℋ  ∧  ∀ 𝑦  ∈   Cℋ  ( 𝑦  ⊆  𝐴  →  ( 𝑦  =  𝐴  ∨  𝑦  =  0ℋ ) ) ) )  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 41 | 
							
								1 40
							 | 
							sylbi | 
							⊢ ( 𝐴  ∈  HAtoms  →  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 42 | 
							
								
							 | 
							h1da | 
							⊢ ( ( 𝑥  ∈   ℋ  ∧  𝑥  ≠  0ℎ )  →  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ∈  HAtoms )  | 
						
						
							| 43 | 
							
								
							 | 
							eleq1 | 
							⊢ ( 𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  ( 𝐴  ∈  HAtoms  ↔  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  ∈  HAtoms ) )  | 
						
						
							| 44 | 
							
								42 43
							 | 
							imbitrrid | 
							⊢ ( 𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  ( ( 𝑥  ∈   ℋ  ∧  𝑥  ≠  0ℎ )  →  𝐴  ∈  HAtoms ) )  | 
						
						
							| 45 | 
							
								44
							 | 
							expdcom | 
							⊢ ( 𝑥  ∈   ℋ  →  ( 𝑥  ≠  0ℎ  →  ( 𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) )  →  𝐴  ∈  HAtoms ) ) )  | 
						
						
							| 46 | 
							
								45
							 | 
							impd | 
							⊢ ( 𝑥  ∈   ℋ  →  ( ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) )  →  𝐴  ∈  HAtoms ) )  | 
						
						
							| 47 | 
							
								46
							 | 
							rexlimiv | 
							⊢ ( ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) )  →  𝐴  ∈  HAtoms )  | 
						
						
							| 48 | 
							
								41 47
							 | 
							impbii | 
							⊢ ( 𝐴  ∈  HAtoms  ↔  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 49 | 
							
								
							 | 
							spansn | 
							⊢ ( 𝑥  ∈   ℋ  →  ( span ‘ { 𝑥 } )  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) )  | 
						
						
							| 50 | 
							
								49
							 | 
							eqeq2d | 
							⊢ ( 𝑥  ∈   ℋ  →  ( 𝐴  =  ( span ‘ { 𝑥 } )  ↔  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 51 | 
							
								50
							 | 
							anbi2d | 
							⊢ ( 𝑥  ∈   ℋ  →  ( ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( span ‘ { 𝑥 } ) )  ↔  ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) ) )  | 
						
						
							| 52 | 
							
								51
							 | 
							rexbiia | 
							⊢ ( ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( span ‘ { 𝑥 } ) )  ↔  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( ⊥ ‘ ( ⊥ ‘ { 𝑥 } ) ) ) )  | 
						
						
							| 53 | 
							
								48 52
							 | 
							bitr4i | 
							⊢ ( 𝐴  ∈  HAtoms  ↔  ∃ 𝑥  ∈   ℋ ( 𝑥  ≠  0ℎ  ∧  𝐴  =  ( span ‘ { 𝑥 } ) ) )  |