| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							atmod.b | 
							⊢ 𝐵  =  ( Base ‘ 𝐾 )  | 
						
						
							| 2 | 
							
								
							 | 
							atmod.l | 
							⊢  ≤   =  ( le ‘ 𝐾 )  | 
						
						
							| 3 | 
							
								
							 | 
							atmod.j | 
							⊢  ∨   =  ( join ‘ 𝐾 )  | 
						
						
							| 4 | 
							
								
							 | 
							atmod.m | 
							⊢  ∧   =  ( meet ‘ 𝐾 )  | 
						
						
							| 5 | 
							
								
							 | 
							atmod.a | 
							⊢ 𝐴  =  ( Atoms ‘ 𝐾 )  | 
						
						
							| 6 | 
							
								
							 | 
							hllat | 
							⊢ ( 𝐾  ∈  HL  →  𝐾  ∈  Lat )  | 
						
						
							| 7 | 
							
								6
							 | 
							3ad2ant1 | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  𝐾  ∈  Lat )  | 
						
						
							| 8 | 
							
								
							 | 
							simp22 | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  𝑋  ∈  𝐵 )  | 
						
						
							| 9 | 
							
								
							 | 
							simp23 | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  𝑌  ∈  𝐵 )  | 
						
						
							| 10 | 
							
								1 4
							 | 
							latmcl | 
							⊢ ( ( 𝐾  ∈  Lat  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  →  ( 𝑋  ∧  𝑌 )  ∈  𝐵 )  | 
						
						
							| 11 | 
							
								7 8 9 10
							 | 
							syl3anc | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  ( 𝑋  ∧  𝑌 )  ∈  𝐵 )  | 
						
						
							| 12 | 
							
								
							 | 
							simp21 | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  𝑃  ∈  𝐴 )  | 
						
						
							| 13 | 
							
								1 5
							 | 
							atbase | 
							⊢ ( 𝑃  ∈  𝐴  →  𝑃  ∈  𝐵 )  | 
						
						
							| 14 | 
							
								12 13
							 | 
							syl | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  𝑃  ∈  𝐵 )  | 
						
						
							| 15 | 
							
								1 3
							 | 
							latjcom | 
							⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑋  ∧  𝑌 )  ∈  𝐵  ∧  𝑃  ∈  𝐵 )  →  ( ( 𝑋  ∧  𝑌 )  ∨  𝑃 )  =  ( 𝑃  ∨  ( 𝑋  ∧  𝑌 ) ) )  | 
						
						
							| 16 | 
							
								7 11 14 15
							 | 
							syl3anc | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  ( ( 𝑋  ∧  𝑌 )  ∨  𝑃 )  =  ( 𝑃  ∨  ( 𝑋  ∧  𝑌 ) ) )  | 
						
						
							| 17 | 
							
								1 2 3 4 5
							 | 
							atmod1i1 | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  ( 𝑃  ∨  ( 𝑋  ∧  𝑌 ) )  =  ( ( 𝑃  ∨  𝑋 )  ∧  𝑌 ) )  | 
						
						
							| 18 | 
							
								1 3
							 | 
							latjcom | 
							⊢ ( ( 𝐾  ∈  Lat  ∧  𝑃  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  →  ( 𝑃  ∨  𝑋 )  =  ( 𝑋  ∨  𝑃 ) )  | 
						
						
							| 19 | 
							
								7 14 8 18
							 | 
							syl3anc | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  ( 𝑃  ∨  𝑋 )  =  ( 𝑋  ∨  𝑃 ) )  | 
						
						
							| 20 | 
							
								19
							 | 
							oveq1d | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  ( ( 𝑃  ∨  𝑋 )  ∧  𝑌 )  =  ( ( 𝑋  ∨  𝑃 )  ∧  𝑌 ) )  | 
						
						
							| 21 | 
							
								16 17 20
							 | 
							3eqtrd | 
							⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑃  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  ∧  𝑃  ≤  𝑌 )  →  ( ( 𝑋  ∧  𝑌 )  ∨  𝑃 )  =  ( ( 𝑋  ∨  𝑃 )  ∧  𝑌 ) )  |