| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							olm0.b | 
							 |-  B = ( Base ` K )  | 
						
						
							| 2 | 
							
								
							 | 
							olm0.m | 
							 |-  ./\ = ( meet ` K )  | 
						
						
							| 3 | 
							
								
							 | 
							olm0.z | 
							 |-  .0. = ( 0. ` K )  | 
						
						
							| 4 | 
							
								
							 | 
							eqid | 
							 |-  ( le ` K ) = ( le ` K )  | 
						
						
							| 5 | 
							
								
							 | 
							ollat | 
							 |-  ( K e. OL -> K e. Lat )  | 
						
						
							| 6 | 
							
								5
							 | 
							adantr | 
							 |-  ( ( K e. OL /\ X e. B ) -> K e. Lat )  | 
						
						
							| 7 | 
							
								
							 | 
							simpr | 
							 |-  ( ( K e. OL /\ X e. B ) -> X e. B )  | 
						
						
							| 8 | 
							
								
							 | 
							olop | 
							 |-  ( K e. OL -> K e. OP )  | 
						
						
							| 9 | 
							
								8
							 | 
							adantr | 
							 |-  ( ( K e. OL /\ X e. B ) -> K e. OP )  | 
						
						
							| 10 | 
							
								1 3
							 | 
							op0cl | 
							 |-  ( K e. OP -> .0. e. B )  | 
						
						
							| 11 | 
							
								9 10
							 | 
							syl | 
							 |-  ( ( K e. OL /\ X e. B ) -> .0. e. B )  | 
						
						
							| 12 | 
							
								1 2
							 | 
							latmcl | 
							 |-  ( ( K e. Lat /\ X e. B /\ .0. e. B ) -> ( X ./\ .0. ) e. B )  | 
						
						
							| 13 | 
							
								6 7 11 12
							 | 
							syl3anc | 
							 |-  ( ( K e. OL /\ X e. B ) -> ( X ./\ .0. ) e. B )  | 
						
						
							| 14 | 
							
								1 4 2
							 | 
							latmle2 | 
							 |-  ( ( K e. Lat /\ X e. B /\ .0. e. B ) -> ( X ./\ .0. ) ( le ` K ) .0. )  | 
						
						
							| 15 | 
							
								6 7 11 14
							 | 
							syl3anc | 
							 |-  ( ( K e. OL /\ X e. B ) -> ( X ./\ .0. ) ( le ` K ) .0. )  | 
						
						
							| 16 | 
							
								1 4 3
							 | 
							op0le | 
							 |-  ( ( K e. OP /\ X e. B ) -> .0. ( le ` K ) X )  | 
						
						
							| 17 | 
							
								8 16
							 | 
							sylan | 
							 |-  ( ( K e. OL /\ X e. B ) -> .0. ( le ` K ) X )  | 
						
						
							| 18 | 
							
								1 4
							 | 
							latref | 
							 |-  ( ( K e. Lat /\ .0. e. B ) -> .0. ( le ` K ) .0. )  | 
						
						
							| 19 | 
							
								6 11 18
							 | 
							syl2anc | 
							 |-  ( ( K e. OL /\ X e. B ) -> .0. ( le ` K ) .0. )  | 
						
						
							| 20 | 
							
								1 4 2
							 | 
							latlem12 | 
							 |-  ( ( K e. Lat /\ ( .0. e. B /\ X e. B /\ .0. e. B ) ) -> ( ( .0. ( le ` K ) X /\ .0. ( le ` K ) .0. ) <-> .0. ( le ` K ) ( X ./\ .0. ) ) )  | 
						
						
							| 21 | 
							
								6 11 7 11 20
							 | 
							syl13anc | 
							 |-  ( ( K e. OL /\ X e. B ) -> ( ( .0. ( le ` K ) X /\ .0. ( le ` K ) .0. ) <-> .0. ( le ` K ) ( X ./\ .0. ) ) )  | 
						
						
							| 22 | 
							
								17 19 21
							 | 
							mpbi2and | 
							 |-  ( ( K e. OL /\ X e. B ) -> .0. ( le ` K ) ( X ./\ .0. ) )  | 
						
						
							| 23 | 
							
								1 4 6 13 11 15 22
							 | 
							latasymd | 
							 |-  ( ( K e. OL /\ X e. B ) -> ( X ./\ .0. ) = .0. )  |