| Step | Hyp | Ref | Expression | 
						
							| 1 |  | lnnat.j |  |-  .\/ = ( join ` K ) | 
						
							| 2 |  | lnnat.a |  |-  A = ( Atoms ` K ) | 
						
							| 3 |  | simpl1 |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> K e. HL ) | 
						
							| 4 |  | simpl2 |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> P e. A ) | 
						
							| 5 |  | eqid |  |-  ( 0. ` K ) = ( 0. ` K ) | 
						
							| 6 |  | eqid |  |-  (  | 
						
							| 7 | 5 6 2 | atcvr0 |  |-  ( ( K e. HL /\ P e. A ) -> ( 0. ` K ) (  | 
						
							| 8 | 3 4 7 | syl2anc |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> ( 0. ` K ) (  | 
						
							| 9 | 1 6 2 | atcvr1 |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( P =/= Q <-> P (  | 
						
							| 10 | 9 | biimpa |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> P (  | 
						
							| 11 |  | hlop |  |-  ( K e. HL -> K e. OP ) | 
						
							| 12 |  | eqid |  |-  ( Base ` K ) = ( Base ` K ) | 
						
							| 13 | 12 5 | op0cl |  |-  ( K e. OP -> ( 0. ` K ) e. ( Base ` K ) ) | 
						
							| 14 | 3 11 13 | 3syl |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> ( 0. ` K ) e. ( Base ` K ) ) | 
						
							| 15 | 12 2 | atbase |  |-  ( P e. A -> P e. ( Base ` K ) ) | 
						
							| 16 | 4 15 | syl |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> P e. ( Base ` K ) ) | 
						
							| 17 | 3 | hllatd |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> K e. Lat ) | 
						
							| 18 |  | simpl3 |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> Q e. A ) | 
						
							| 19 | 12 2 | atbase |  |-  ( Q e. A -> Q e. ( Base ` K ) ) | 
						
							| 20 | 18 19 | syl |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> Q e. ( Base ` K ) ) | 
						
							| 21 | 12 1 | latjcl |  |-  ( ( K e. Lat /\ P e. ( Base ` K ) /\ Q e. ( Base ` K ) ) -> ( P .\/ Q ) e. ( Base ` K ) ) | 
						
							| 22 | 17 16 20 21 | syl3anc |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> ( P .\/ Q ) e. ( Base ` K ) ) | 
						
							| 23 | 12 6 | cvrntr |  |-  ( ( K e. HL /\ ( ( 0. ` K ) e. ( Base ` K ) /\ P e. ( Base ` K ) /\ ( P .\/ Q ) e. ( Base ` K ) ) ) -> ( ( ( 0. ` K ) (  -. ( 0. ` K ) (  | 
						
							| 24 | 3 14 16 22 23 | syl13anc |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> ( ( ( 0. ` K ) (  -. ( 0. ` K ) (  | 
						
							| 25 | 8 10 24 | mp2and |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> -. ( 0. ` K ) (  | 
						
							| 26 |  | simpll1 |  |-  ( ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) /\ ( P .\/ Q ) e. A ) -> K e. HL ) | 
						
							| 27 | 5 6 2 | atcvr0 |  |-  ( ( K e. HL /\ ( P .\/ Q ) e. A ) -> ( 0. ` K ) (  | 
						
							| 28 | 26 27 | sylancom |  |-  ( ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) /\ ( P .\/ Q ) e. A ) -> ( 0. ` K ) (  | 
						
							| 29 | 25 28 | mtand |  |-  ( ( ( K e. HL /\ P e. A /\ Q e. A ) /\ P =/= Q ) -> -. ( P .\/ Q ) e. A ) | 
						
							| 30 | 29 | ex |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( P =/= Q -> -. ( P .\/ Q ) e. A ) ) | 
						
							| 31 | 1 2 | hlatjidm |  |-  ( ( K e. HL /\ P e. A ) -> ( P .\/ P ) = P ) | 
						
							| 32 | 31 | 3adant3 |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( P .\/ P ) = P ) | 
						
							| 33 |  | simp2 |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> P e. A ) | 
						
							| 34 | 32 33 | eqeltrd |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( P .\/ P ) e. A ) | 
						
							| 35 |  | oveq2 |  |-  ( P = Q -> ( P .\/ P ) = ( P .\/ Q ) ) | 
						
							| 36 | 35 | eleq1d |  |-  ( P = Q -> ( ( P .\/ P ) e. A <-> ( P .\/ Q ) e. A ) ) | 
						
							| 37 | 34 36 | syl5ibcom |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( P = Q -> ( P .\/ Q ) e. A ) ) | 
						
							| 38 | 37 | necon3bd |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( -. ( P .\/ Q ) e. A -> P =/= Q ) ) | 
						
							| 39 | 30 38 | impbid |  |-  ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( P =/= Q <-> -. ( P .\/ Q ) e. A ) ) |