| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cdlemg12.l | ⊢  ≤   =  ( le ‘ 𝐾 ) | 
						
							| 2 |  | cdlemg12.j | ⊢  ∨   =  ( join ‘ 𝐾 ) | 
						
							| 3 |  | cdlemg12.m | ⊢  ∧   =  ( meet ‘ 𝐾 ) | 
						
							| 4 |  | cdlemg12.a | ⊢ 𝐴  =  ( Atoms ‘ 𝐾 ) | 
						
							| 5 |  | cdlemg12.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 6 |  | cdlemg12.t | ⊢ 𝑇  =  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 7 |  | cdlemg12b.r | ⊢ 𝑅  =  ( ( trL ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 8 |  | simp1 | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 9 |  | simp31 | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  𝐹  ∈  𝑇 ) | 
						
							| 10 |  | simp2l | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 ) ) | 
						
							| 11 |  | simp2r | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) ) | 
						
							| 12 | 1 2 3 4 5 6 | ltrnu | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇 )  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  →  ( ( 𝑃  ∨  ( 𝐹 ‘ 𝑃 ) )  ∧  𝑊 )  =  ( ( 𝑄  ∨  ( 𝐹 ‘ 𝑄 ) )  ∧  𝑊 ) ) | 
						
							| 13 | 8 9 10 11 12 | syl211anc | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( ( 𝑃  ∨  ( 𝐹 ‘ 𝑃 ) )  ∧  𝑊 )  =  ( ( 𝑄  ∨  ( 𝐹 ‘ 𝑄 ) )  ∧  𝑊 ) ) | 
						
							| 14 |  | simp33 | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) | 
						
							| 15 | 14 | fveq2d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝐹 ‘ ( 𝐺 ‘ 𝑃 ) )  =  ( 𝐹 ‘ 𝑃 ) ) | 
						
							| 16 | 15 | oveq2d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝑃  ∨  ( 𝐹 ‘ ( 𝐺 ‘ 𝑃 ) ) )  =  ( 𝑃  ∨  ( 𝐹 ‘ 𝑃 ) ) ) | 
						
							| 17 | 16 | oveq1d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( ( 𝑃  ∨  ( 𝐹 ‘ ( 𝐺 ‘ 𝑃 ) ) )  ∧  𝑊 )  =  ( ( 𝑃  ∨  ( 𝐹 ‘ 𝑃 ) )  ∧  𝑊 ) ) | 
						
							| 18 |  | simp32 | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  𝐺  ∈  𝑇 ) | 
						
							| 19 | 1 4 5 6 | ltrnateq | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝐺  ∈  𝑇  ∧  ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 )  →  ( 𝐺 ‘ 𝑄 )  =  𝑄 ) | 
						
							| 20 | 8 18 10 11 14 19 | syl131anc | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝐺 ‘ 𝑄 )  =  𝑄 ) | 
						
							| 21 | 20 | fveq2d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝐹 ‘ ( 𝐺 ‘ 𝑄 ) )  =  ( 𝐹 ‘ 𝑄 ) ) | 
						
							| 22 | 21 | oveq2d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( 𝑄  ∨  ( 𝐹 ‘ ( 𝐺 ‘ 𝑄 ) ) )  =  ( 𝑄  ∨  ( 𝐹 ‘ 𝑄 ) ) ) | 
						
							| 23 | 22 | oveq1d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( ( 𝑄  ∨  ( 𝐹 ‘ ( 𝐺 ‘ 𝑄 ) ) )  ∧  𝑊 )  =  ( ( 𝑄  ∨  ( 𝐹 ‘ 𝑄 ) )  ∧  𝑊 ) ) | 
						
							| 24 | 13 17 23 | 3eqtr4d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( ( 𝑃  ∈  𝐴  ∧  ¬  𝑃  ≤  𝑊 )  ∧  ( 𝑄  ∈  𝐴  ∧  ¬  𝑄  ≤  𝑊 ) )  ∧  ( 𝐹  ∈  𝑇  ∧  𝐺  ∈  𝑇  ∧  ( 𝐺 ‘ 𝑃 )  =  𝑃 ) )  →  ( ( 𝑃  ∨  ( 𝐹 ‘ ( 𝐺 ‘ 𝑃 ) ) )  ∧  𝑊 )  =  ( ( 𝑄  ∨  ( 𝐹 ‘ ( 𝐺 ‘ 𝑄 ) ) )  ∧  𝑊 ) ) |