| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							latmidm.b | 
							 |-  B = ( Base ` K )  | 
						
						
							| 2 | 
							
								
							 | 
							latmidm.m | 
							 |-  ./\ = ( meet ` K )  | 
						
						
							| 3 | 
							
								
							 | 
							eqid | 
							 |-  ( le ` K ) = ( le ` K )  | 
						
						
							| 4 | 
							
								
							 | 
							simpl | 
							 |-  ( ( K e. Lat /\ X e. B ) -> K e. Lat )  | 
						
						
							| 5 | 
							
								1 2
							 | 
							latmcl | 
							 |-  ( ( K e. Lat /\ X e. B /\ X e. B ) -> ( X ./\ X ) e. B )  | 
						
						
							| 6 | 
							
								5
							 | 
							3anidm23 | 
							 |-  ( ( K e. Lat /\ X e. B ) -> ( X ./\ X ) e. B )  | 
						
						
							| 7 | 
							
								
							 | 
							simpr | 
							 |-  ( ( K e. Lat /\ X e. B ) -> X e. B )  | 
						
						
							| 8 | 
							
								1 3 2
							 | 
							latmle1 | 
							 |-  ( ( K e. Lat /\ X e. B /\ X e. B ) -> ( X ./\ X ) ( le ` K ) X )  | 
						
						
							| 9 | 
							
								8
							 | 
							3anidm23 | 
							 |-  ( ( K e. Lat /\ X e. B ) -> ( X ./\ X ) ( le ` K ) X )  | 
						
						
							| 10 | 
							
								1 3
							 | 
							latref | 
							 |-  ( ( K e. Lat /\ X e. B ) -> X ( le ` K ) X )  | 
						
						
							| 11 | 
							
								1 3 2
							 | 
							latlem12 | 
							 |-  ( ( K e. Lat /\ ( X e. B /\ X e. B /\ X e. B ) ) -> ( ( X ( le ` K ) X /\ X ( le ` K ) X ) <-> X ( le ` K ) ( X ./\ X ) ) )  | 
						
						
							| 12 | 
							
								4 7 7 7 11
							 | 
							syl13anc | 
							 |-  ( ( K e. Lat /\ X e. B ) -> ( ( X ( le ` K ) X /\ X ( le ` K ) X ) <-> X ( le ` K ) ( X ./\ X ) ) )  | 
						
						
							| 13 | 
							
								10 10 12
							 | 
							mpbi2and | 
							 |-  ( ( K e. Lat /\ X e. B ) -> X ( le ` K ) ( X ./\ X ) )  | 
						
						
							| 14 | 
							
								1 3 4 6 7 9 13
							 | 
							latasymd | 
							 |-  ( ( K e. Lat /\ X e. B ) -> ( X ./\ X ) = X )  |