| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							cdleme24.b | 
							⊢ 𝐵  =  ( Base ‘ 𝐾 )  | 
						
						
							| 2 | 
							
								
							 | 
							cdleme24.l | 
							⊢  ≤   =  ( le ‘ 𝐾 )  | 
						
						
							| 3 | 
							
								
							 | 
							cdleme24.j | 
							⊢  ∨   =  ( join ‘ 𝐾 )  | 
						
						
							| 4 | 
							
								
							 | 
							cdleme24.m | 
							⊢  ∧   =  ( meet ‘ 𝐾 )  | 
						
						
							| 5 | 
							
								
							 | 
							cdleme24.a | 
							⊢ 𝐴  =  ( Atoms ‘ 𝐾 )  | 
						
						
							| 6 | 
							
								
							 | 
							cdleme24.h | 
							⊢ 𝐻  =  ( LHyp ‘ 𝐾 )  | 
						
						
							| 7 | 
							
								
							 | 
							cdleme24.u | 
							⊢ 𝑈  =  ( ( 𝑃  ∨  𝑄 )  ∧  𝑊 )  | 
						
						
							| 8 | 
							
								
							 | 
							cdleme24.f | 
							⊢ 𝐹  =  ( ( 𝑠  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑠 )  ∧  𝑊 ) ) )  | 
						
						
							| 9 | 
							
								
							 | 
							cdleme24.n | 
							⊢ 𝑁  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( 𝐹  ∨  ( ( 𝑅  ∨  𝑠 )  ∧  𝑊 ) ) )  | 
						
						
							| 10 | 
							
								1 2 3 4 5 6 7 8 9
							 | 
							cdleme25a | 
							⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝑅  ∈  𝐴  ∧  ¬  𝑅  ≤  𝑊 )  ∧  ( 𝑃  ≠  𝑄  ∧  𝑅  ≤  ( 𝑃  ∨  𝑄 ) ) )  →  ∃ 𝑠  ∈  𝐴 ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  ∧  𝑁  ∈  𝐵 ) )  | 
						
						
							| 11 | 
							
								
							 | 
							eqid | 
							⊢ ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  =  ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  | 
						
						
							| 12 | 
							
								
							 | 
							eqid | 
							⊢ ( ( 𝑃  ∨  𝑄 )  ∧  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) )  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) )  | 
						
						
							| 13 | 
							
								1 2 3 4 5 6 7 8 9 11 12
							 | 
							cdleme24 | 
							⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝑅  ∈  𝐴  ∧  ¬  𝑅  ≤  𝑊 )  ∧  ( 𝑃  ≠  𝑄  ∧  𝑅  ≤  ( 𝑃  ∨  𝑄 ) ) )  →  ∀ 𝑠  ∈  𝐴 ∀ 𝑡  ∈  𝐴 ( ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  ∧  ( ¬  𝑡  ≤  𝑊  ∧  ¬  𝑡  ≤  ( 𝑃  ∨  𝑄 ) ) )  →  𝑁  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) ) ) )  | 
						
						
							| 14 | 
							
								
							 | 
							breq1 | 
							⊢ ( 𝑠  =  𝑡  →  ( 𝑠  ≤  𝑊  ↔  𝑡  ≤  𝑊 ) )  | 
						
						
							| 15 | 
							
								14
							 | 
							notbid | 
							⊢ ( 𝑠  =  𝑡  →  ( ¬  𝑠  ≤  𝑊  ↔  ¬  𝑡  ≤  𝑊 ) )  | 
						
						
							| 16 | 
							
								
							 | 
							breq1 | 
							⊢ ( 𝑠  =  𝑡  →  ( 𝑠  ≤  ( 𝑃  ∨  𝑄 )  ↔  𝑡  ≤  ( 𝑃  ∨  𝑄 ) ) )  | 
						
						
							| 17 | 
							
								16
							 | 
							notbid | 
							⊢ ( 𝑠  =  𝑡  →  ( ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 )  ↔  ¬  𝑡  ≤  ( 𝑃  ∨  𝑄 ) ) )  | 
						
						
							| 18 | 
							
								15 17
							 | 
							anbi12d | 
							⊢ ( 𝑠  =  𝑡  →  ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  ↔  ( ¬  𝑡  ≤  𝑊  ∧  ¬  𝑡  ≤  ( 𝑃  ∨  𝑄 ) ) ) )  | 
						
						
							| 19 | 
							
								
							 | 
							oveq1 | 
							⊢ ( 𝑠  =  𝑡  →  ( 𝑠  ∨  𝑈 )  =  ( 𝑡  ∨  𝑈 ) )  | 
						
						
							| 20 | 
							
								
							 | 
							oveq2 | 
							⊢ ( 𝑠  =  𝑡  →  ( 𝑃  ∨  𝑠 )  =  ( 𝑃  ∨  𝑡 ) )  | 
						
						
							| 21 | 
							
								20
							 | 
							oveq1d | 
							⊢ ( 𝑠  =  𝑡  →  ( ( 𝑃  ∨  𝑠 )  ∧  𝑊 )  =  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) )  | 
						
						
							| 22 | 
							
								21
							 | 
							oveq2d | 
							⊢ ( 𝑠  =  𝑡  →  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑠 )  ∧  𝑊 ) )  =  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  | 
						
						
							| 23 | 
							
								19 22
							 | 
							oveq12d | 
							⊢ ( 𝑠  =  𝑡  →  ( ( 𝑠  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑠 )  ∧  𝑊 ) ) )  =  ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) ) )  | 
						
						
							| 24 | 
							
								8 23
							 | 
							eqtrid | 
							⊢ ( 𝑠  =  𝑡  →  𝐹  =  ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) ) )  | 
						
						
							| 25 | 
							
								
							 | 
							oveq2 | 
							⊢ ( 𝑠  =  𝑡  →  ( 𝑅  ∨  𝑠 )  =  ( 𝑅  ∨  𝑡 ) )  | 
						
						
							| 26 | 
							
								25
							 | 
							oveq1d | 
							⊢ ( 𝑠  =  𝑡  →  ( ( 𝑅  ∨  𝑠 )  ∧  𝑊 )  =  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) )  | 
						
						
							| 27 | 
							
								24 26
							 | 
							oveq12d | 
							⊢ ( 𝑠  =  𝑡  →  ( 𝐹  ∨  ( ( 𝑅  ∨  𝑠 )  ∧  𝑊 ) )  =  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) )  | 
						
						
							| 28 | 
							
								27
							 | 
							oveq2d | 
							⊢ ( 𝑠  =  𝑡  →  ( ( 𝑃  ∨  𝑄 )  ∧  ( 𝐹  ∨  ( ( 𝑅  ∨  𝑠 )  ∧  𝑊 ) ) )  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) ) )  | 
						
						
							| 29 | 
							
								9 28
							 | 
							eqtrid | 
							⊢ ( 𝑠  =  𝑡  →  𝑁  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) ) )  | 
						
						
							| 30 | 
							
								18 29
							 | 
							reusv3 | 
							⊢ ( ∃ 𝑠  ∈  𝐴 ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  ∧  𝑁  ∈  𝐵 )  →  ( ∀ 𝑠  ∈  𝐴 ∀ 𝑡  ∈  𝐴 ( ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  ∧  ( ¬  𝑡  ≤  𝑊  ∧  ¬  𝑡  ≤  ( 𝑃  ∨  𝑄 ) ) )  →  𝑁  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) ) )  ↔  ∃ 𝑢  ∈  𝐵 ∀ 𝑠  ∈  𝐴 ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  →  𝑢  =  𝑁 ) ) )  | 
						
						
							| 31 | 
							
								30
							 | 
							biimpd | 
							⊢ ( ∃ 𝑠  ∈  𝐴 ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  ∧  𝑁  ∈  𝐵 )  →  ( ∀ 𝑠  ∈  𝐴 ∀ 𝑡  ∈  𝐴 ( ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  ∧  ( ¬  𝑡  ≤  𝑊  ∧  ¬  𝑡  ≤  ( 𝑃  ∨  𝑄 ) ) )  →  𝑁  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( ( ( 𝑡  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑡 )  ∧  𝑊 ) ) )  ∨  ( ( 𝑅  ∨  𝑡 )  ∧  𝑊 ) ) ) )  →  ∃ 𝑢  ∈  𝐵 ∀ 𝑠  ∈  𝐴 ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  →  𝑢  =  𝑁 ) ) )  | 
						
						
							| 32 | 
							
								10 13 31
							 | 
							sylc | 
							⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝑅  ∈  𝐴  ∧  ¬  𝑅  ≤  𝑊 )  ∧  ( 𝑃  ≠  𝑄  ∧  𝑅  ≤  ( 𝑃  ∨  𝑄 ) ) )  →  ∃ 𝑢  ∈  𝐵 ∀ 𝑠  ∈  𝐴 ( ( ¬  𝑠  ≤  𝑊  ∧  ¬  𝑠  ≤  ( 𝑃  ∨  𝑄 ) )  →  𝑢  =  𝑁 ) )  |