| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							dalem.ph | 
							 |-  ( ph <-> ( ( ( K e. HL /\ C e. ( Base ` K ) ) /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A /\ U e. A ) ) /\ ( Y e. O /\ Z e. O ) /\ ( ( -. C .<_ ( P .\/ Q ) /\ -. C .<_ ( Q .\/ R ) /\ -. C .<_ ( R .\/ P ) ) /\ ( -. C .<_ ( S .\/ T ) /\ -. C .<_ ( T .\/ U ) /\ -. C .<_ ( U .\/ S ) ) /\ ( C .<_ ( P .\/ S ) /\ C .<_ ( Q .\/ T ) /\ C .<_ ( R .\/ U ) ) ) ) )  | 
						
						
							| 2 | 
							
								
							 | 
							dalem.l | 
							 |-  .<_ = ( le ` K )  | 
						
						
							| 3 | 
							
								
							 | 
							dalem.j | 
							 |-  .\/ = ( join ` K )  | 
						
						
							| 4 | 
							
								
							 | 
							dalem.a | 
							 |-  A = ( Atoms ` K )  | 
						
						
							| 5 | 
							
								
							 | 
							dalem.ps | 
							 |-  ( ps <-> ( ( c e. A /\ d e. A ) /\ -. c .<_ Y /\ ( d =/= c /\ -. d .<_ Y /\ C .<_ ( c .\/ d ) ) ) )  | 
						
						
							| 6 | 
							
								
							 | 
							dalem38.m | 
							 |-  ./\ = ( meet ` K )  | 
						
						
							| 7 | 
							
								
							 | 
							dalem38.o | 
							 |-  O = ( LPlanes ` K )  | 
						
						
							| 8 | 
							
								
							 | 
							dalem38.y | 
							 |-  Y = ( ( P .\/ Q ) .\/ R )  | 
						
						
							| 9 | 
							
								
							 | 
							dalem38.z | 
							 |-  Z = ( ( S .\/ T ) .\/ U )  | 
						
						
							| 10 | 
							
								
							 | 
							dalem38.g | 
							 |-  G = ( ( c .\/ P ) ./\ ( d .\/ S ) )  | 
						
						
							| 11 | 
							
								
							 | 
							dalem38.h | 
							 |-  H = ( ( c .\/ Q ) ./\ ( d .\/ T ) )  | 
						
						
							| 12 | 
							
								
							 | 
							dalem38.i | 
							 |-  I = ( ( c .\/ R ) ./\ ( d .\/ U ) )  | 
						
						
							| 13 | 
							
								1
							 | 
							dalemkehl | 
							 |-  ( ph -> K e. HL )  | 
						
						
							| 14 | 
							
								13
							 | 
							3ad2ant1 | 
							 |-  ( ( ph /\ Y = Z /\ ps ) -> K e. HL )  | 
						
						
							| 15 | 
							
								1 2 3 4 5 6 7 8 9 11
							 | 
							dalem29 | 
							 |-  ( ( ph /\ Y = Z /\ ps ) -> H e. A )  | 
						
						
							| 16 | 
							
								1 2 3 4 5 6 7 8 9 12
							 | 
							dalem34 | 
							 |-  ( ( ph /\ Y = Z /\ ps ) -> I e. A )  | 
						
						
							| 17 | 
							
								1 2 3 4 5 6 7 8 9 10
							 | 
							dalem23 | 
							 |-  ( ( ph /\ Y = Z /\ ps ) -> G e. A )  | 
						
						
							| 18 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12
							 | 
							dalem39 | 
							 |-  ( ( ph /\ Y = Z /\ ps ) -> -. H .<_ ( I .\/ G ) )  | 
						
						
							| 19 | 
							
								2 3 4
							 | 
							atnlej2 | 
							 |-  ( ( K e. HL /\ ( H e. A /\ I e. A /\ G e. A ) /\ -. H .<_ ( I .\/ G ) ) -> H =/= G )  | 
						
						
							| 20 | 
							
								14 15 16 17 18 19
							 | 
							syl131anc | 
							 |-  ( ( ph /\ Y = Z /\ ps ) -> H =/= G )  | 
						
						
							| 21 | 
							
								20
							 | 
							necomd | 
							 |-  ( ( ph /\ Y = Z /\ ps ) -> G =/= H )  |