| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							cdleme12.l | 
							⊢  ≤   =  ( le ‘ 𝐾 )  | 
						
						
							| 2 | 
							
								
							 | 
							cdleme12.j | 
							⊢  ∨   =  ( join ‘ 𝐾 )  | 
						
						
							| 3 | 
							
								
							 | 
							cdleme12.m | 
							⊢  ∧   =  ( meet ‘ 𝐾 )  | 
						
						
							| 4 | 
							
								
							 | 
							cdleme12.a | 
							⊢ 𝐴  =  ( Atoms ‘ 𝐾 )  | 
						
						
							| 5 | 
							
								
							 | 
							cdleme12.h | 
							⊢ 𝐻  =  ( LHyp ‘ 𝐾 )  | 
						
						
							| 6 | 
							
								
							 | 
							cdleme12.u | 
							⊢ 𝑈  =  ( ( 𝑃  ∨  𝑄 )  ∧  𝑊 )  | 
						
						
							| 7 | 
							
								
							 | 
							cdleme12.f | 
							⊢ 𝐹  =  ( ( 𝑆  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑆 )  ∧  𝑊 ) ) )  | 
						
						
							| 8 | 
							
								
							 | 
							cdleme12.g | 
							⊢ 𝐺  =  ( ( 𝑇  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑇 )  ∧  𝑊 ) ) )  | 
						
						
							| 9 | 
							
								1 2 3 4 5 6 7 8
							 | 
							cdleme16e | 
							⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( ( 𝑆  ∈  𝐴  ∧  ¬  𝑆  ≤  𝑊 )  ∧  ( 𝑇  ∈  𝐴  ∧  ¬  𝑇  ≤  𝑊 )  ∧  ( 𝑃  ≠  𝑄  ∧  𝑆  ≠  𝑇 ) )  ∧  ( ¬  𝑆  ≤  ( 𝑃  ∨  𝑄 )  ∧  ¬  𝑇  ≤  ( 𝑃  ∨  𝑄 )  ∧  ¬  𝑈  ≤  ( 𝑆  ∨  𝑇 ) ) )  →  ( ( 𝑆  ∨  𝑇 )  ∧  ( 𝐹  ∨  𝐺 ) )  =  ( ( 𝑆  ∨  𝑇 )  ∧  𝑊 ) )  | 
						
						
							| 10 | 
							
								1 2 3 4 5 6 7 8
							 | 
							cdleme16f | 
							⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( ( 𝑆  ∈  𝐴  ∧  ¬  𝑆  ≤  𝑊 )  ∧  ( 𝑇  ∈  𝐴  ∧  ¬  𝑇  ≤  𝑊 )  ∧  ( 𝑃  ≠  𝑄  ∧  𝑆  ≠  𝑇 ) )  ∧  ( ¬  𝑆  ≤  ( 𝑃  ∨  𝑄 )  ∧  ¬  𝑇  ≤  ( 𝑃  ∨  𝑄 )  ∧  ¬  𝑈  ≤  ( 𝑆  ∨  𝑇 ) ) )  →  ( ( 𝑆  ∨  𝑇 )  ∧  ( 𝐹  ∨  𝐺 ) )  =  ( ( 𝐹  ∨  𝐺 )  ∧  𝑊 ) )  | 
						
						
							| 11 | 
							
								9 10
							 | 
							eqtr3d | 
							⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( ( 𝑆  ∈  𝐴  ∧  ¬  𝑆  ≤  𝑊 )  ∧  ( 𝑇  ∈  𝐴  ∧  ¬  𝑇  ≤  𝑊 )  ∧  ( 𝑃  ≠  𝑄  ∧  𝑆  ≠  𝑇 ) )  ∧  ( ¬  𝑆  ≤  ( 𝑃  ∨  𝑄 )  ∧  ¬  𝑇  ≤  ( 𝑃  ∨  𝑄 )  ∧  ¬  𝑈  ≤  ( 𝑆  ∨  𝑇 ) ) )  →  ( ( 𝑆  ∨  𝑇 )  ∧  𝑊 )  =  ( ( 𝐹  ∨  𝐺 )  ∧  𝑊 ) )  |