| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 0 | 
							
								
							 | 
							coml | 
							 |-  OML  | 
						
						
							| 1 | 
							
								
							 | 
							vl | 
							 |-  l  | 
						
						
							| 2 | 
							
								
							 | 
							col | 
							 |-  OL  | 
						
						
							| 3 | 
							
								
							 | 
							va | 
							 |-  a  | 
						
						
							| 4 | 
							
								
							 | 
							cbs | 
							 |-  Base  | 
						
						
							| 5 | 
							
								1
							 | 
							cv | 
							 |-  l  | 
						
						
							| 6 | 
							
								5 4
							 | 
							cfv | 
							 |-  ( Base ` l )  | 
						
						
							| 7 | 
							
								
							 | 
							vb | 
							 |-  b  | 
						
						
							| 8 | 
							
								3
							 | 
							cv | 
							 |-  a  | 
						
						
							| 9 | 
							
								
							 | 
							cple | 
							 |-  le  | 
						
						
							| 10 | 
							
								5 9
							 | 
							cfv | 
							 |-  ( le ` l )  | 
						
						
							| 11 | 
							
								7
							 | 
							cv | 
							 |-  b  | 
						
						
							| 12 | 
							
								8 11 10
							 | 
							wbr | 
							 |-  a ( le ` l ) b  | 
						
						
							| 13 | 
							
								
							 | 
							cjn | 
							 |-  join  | 
						
						
							| 14 | 
							
								5 13
							 | 
							cfv | 
							 |-  ( join ` l )  | 
						
						
							| 15 | 
							
								
							 | 
							cmee | 
							 |-  meet  | 
						
						
							| 16 | 
							
								5 15
							 | 
							cfv | 
							 |-  ( meet ` l )  | 
						
						
							| 17 | 
							
								
							 | 
							coc | 
							 |-  oc  | 
						
						
							| 18 | 
							
								5 17
							 | 
							cfv | 
							 |-  ( oc ` l )  | 
						
						
							| 19 | 
							
								8 18
							 | 
							cfv | 
							 |-  ( ( oc ` l ) ` a )  | 
						
						
							| 20 | 
							
								11 19 16
							 | 
							co | 
							 |-  ( b ( meet ` l ) ( ( oc ` l ) ` a ) )  | 
						
						
							| 21 | 
							
								8 20 14
							 | 
							co | 
							 |-  ( a ( join ` l ) ( b ( meet ` l ) ( ( oc ` l ) ` a ) ) )  | 
						
						
							| 22 | 
							
								11 21
							 | 
							wceq | 
							 |-  b = ( a ( join ` l ) ( b ( meet ` l ) ( ( oc ` l ) ` a ) ) )  | 
						
						
							| 23 | 
							
								12 22
							 | 
							wi | 
							 |-  ( a ( le ` l ) b -> b = ( a ( join ` l ) ( b ( meet ` l ) ( ( oc ` l ) ` a ) ) ) )  | 
						
						
							| 24 | 
							
								23 7 6
							 | 
							wral | 
							 |-  A. b e. ( Base ` l ) ( a ( le ` l ) b -> b = ( a ( join ` l ) ( b ( meet ` l ) ( ( oc ` l ) ` a ) ) ) )  | 
						
						
							| 25 | 
							
								24 3 6
							 | 
							wral | 
							 |-  A. a e. ( Base ` l ) A. b e. ( Base ` l ) ( a ( le ` l ) b -> b = ( a ( join ` l ) ( b ( meet ` l ) ( ( oc ` l ) ` a ) ) ) )  | 
						
						
							| 26 | 
							
								25 1 2
							 | 
							crab | 
							 |-  { l e. OL | A. a e. ( Base ` l ) A. b e. ( Base ` l ) ( a ( le ` l ) b -> b = ( a ( join ` l ) ( b ( meet ` l ) ( ( oc ` l ) ` a ) ) ) ) } | 
						
						
							| 27 | 
							
								0 26
							 | 
							wceq | 
							 |-  OML = { l e. OL | A. a e. ( Base ` l ) A. b e. ( Base ` l ) ( a ( le ` l ) b -> b = ( a ( join ` l ) ( b ( meet ` l ) ( ( oc ` l ) ` a ) ) ) ) } |