| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cvlsupr2.a |  |-  A = ( Atoms ` K ) | 
						
							| 2 |  | cvlsupr2.l |  |-  .<_ = ( le ` K ) | 
						
							| 3 |  | cvlsupr2.j |  |-  .\/ = ( join ` K ) | 
						
							| 4 |  | simpl3 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> P =/= Q ) | 
						
							| 5 | 4 | necomd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> Q =/= P ) | 
						
							| 6 |  | simplr |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = P ) -> ( P .\/ R ) = ( Q .\/ R ) ) | 
						
							| 7 |  | oveq2 |  |-  ( R = P -> ( P .\/ R ) = ( P .\/ P ) ) | 
						
							| 8 |  | oveq2 |  |-  ( R = P -> ( Q .\/ R ) = ( Q .\/ P ) ) | 
						
							| 9 | 7 8 | eqeq12d |  |-  ( R = P -> ( ( P .\/ R ) = ( Q .\/ R ) <-> ( P .\/ P ) = ( Q .\/ P ) ) ) | 
						
							| 10 |  | eqcom |  |-  ( ( P .\/ P ) = ( Q .\/ P ) <-> ( Q .\/ P ) = ( P .\/ P ) ) | 
						
							| 11 | 9 10 | bitrdi |  |-  ( R = P -> ( ( P .\/ R ) = ( Q .\/ R ) <-> ( Q .\/ P ) = ( P .\/ P ) ) ) | 
						
							| 12 | 11 | adantl |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = P ) -> ( ( P .\/ R ) = ( Q .\/ R ) <-> ( Q .\/ P ) = ( P .\/ P ) ) ) | 
						
							| 13 | 6 12 | mpbid |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = P ) -> ( Q .\/ P ) = ( P .\/ P ) ) | 
						
							| 14 |  | simpl1 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> K e. CvLat ) | 
						
							| 15 |  | cvllat |  |-  ( K e. CvLat -> K e. Lat ) | 
						
							| 16 | 14 15 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> K e. Lat ) | 
						
							| 17 |  | simpl21 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> P e. A ) | 
						
							| 18 |  | eqid |  |-  ( Base ` K ) = ( Base ` K ) | 
						
							| 19 | 18 1 | atbase |  |-  ( P e. A -> P e. ( Base ` K ) ) | 
						
							| 20 | 17 19 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> P e. ( Base ` K ) ) | 
						
							| 21 | 18 3 | latjidm |  |-  ( ( K e. Lat /\ P e. ( Base ` K ) ) -> ( P .\/ P ) = P ) | 
						
							| 22 | 16 20 21 | syl2anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( P .\/ P ) = P ) | 
						
							| 23 | 22 | adantr |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = P ) -> ( P .\/ P ) = P ) | 
						
							| 24 | 13 23 | eqtrd |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = P ) -> ( Q .\/ P ) = P ) | 
						
							| 25 | 24 | ex |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( R = P -> ( Q .\/ P ) = P ) ) | 
						
							| 26 |  | simpl22 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> Q e. A ) | 
						
							| 27 | 18 1 | atbase |  |-  ( Q e. A -> Q e. ( Base ` K ) ) | 
						
							| 28 | 26 27 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> Q e. ( Base ` K ) ) | 
						
							| 29 | 18 2 3 | latleeqj1 |  |-  ( ( K e. Lat /\ Q e. ( Base ` K ) /\ P e. ( Base ` K ) ) -> ( Q .<_ P <-> ( Q .\/ P ) = P ) ) | 
						
							| 30 | 16 28 20 29 | syl3anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( Q .<_ P <-> ( Q .\/ P ) = P ) ) | 
						
							| 31 |  | cvlatl |  |-  ( K e. CvLat -> K e. AtLat ) | 
						
							| 32 | 14 31 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> K e. AtLat ) | 
						
							| 33 | 2 1 | atcmp |  |-  ( ( K e. AtLat /\ Q e. A /\ P e. A ) -> ( Q .<_ P <-> Q = P ) ) | 
						
							| 34 | 32 26 17 33 | syl3anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( Q .<_ P <-> Q = P ) ) | 
						
							| 35 | 30 34 | bitr3d |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( ( Q .\/ P ) = P <-> Q = P ) ) | 
						
							| 36 | 25 35 | sylibd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( R = P -> Q = P ) ) | 
						
							| 37 | 36 | necon3d |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( Q =/= P -> R =/= P ) ) | 
						
							| 38 | 5 37 | mpd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> R =/= P ) | 
						
							| 39 |  | simplr |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = Q ) -> ( P .\/ R ) = ( Q .\/ R ) ) | 
						
							| 40 |  | oveq2 |  |-  ( R = Q -> ( P .\/ R ) = ( P .\/ Q ) ) | 
						
							| 41 |  | oveq2 |  |-  ( R = Q -> ( Q .\/ R ) = ( Q .\/ Q ) ) | 
						
							| 42 | 40 41 | eqeq12d |  |-  ( R = Q -> ( ( P .\/ R ) = ( Q .\/ R ) <-> ( P .\/ Q ) = ( Q .\/ Q ) ) ) | 
						
							| 43 | 42 | adantl |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = Q ) -> ( ( P .\/ R ) = ( Q .\/ R ) <-> ( P .\/ Q ) = ( Q .\/ Q ) ) ) | 
						
							| 44 | 39 43 | mpbid |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = Q ) -> ( P .\/ Q ) = ( Q .\/ Q ) ) | 
						
							| 45 | 18 3 | latjidm |  |-  ( ( K e. Lat /\ Q e. ( Base ` K ) ) -> ( Q .\/ Q ) = Q ) | 
						
							| 46 | 16 28 45 | syl2anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( Q .\/ Q ) = Q ) | 
						
							| 47 | 46 | adantr |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = Q ) -> ( Q .\/ Q ) = Q ) | 
						
							| 48 | 44 47 | eqtrd |  |-  ( ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) /\ R = Q ) -> ( P .\/ Q ) = Q ) | 
						
							| 49 | 48 | ex |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( R = Q -> ( P .\/ Q ) = Q ) ) | 
						
							| 50 | 18 2 3 | latleeqj1 |  |-  ( ( K e. Lat /\ P e. ( Base ` K ) /\ Q e. ( Base ` K ) ) -> ( P .<_ Q <-> ( P .\/ Q ) = Q ) ) | 
						
							| 51 | 16 20 28 50 | syl3anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( P .<_ Q <-> ( P .\/ Q ) = Q ) ) | 
						
							| 52 | 2 1 | atcmp |  |-  ( ( K e. AtLat /\ P e. A /\ Q e. A ) -> ( P .<_ Q <-> P = Q ) ) | 
						
							| 53 | 32 17 26 52 | syl3anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( P .<_ Q <-> P = Q ) ) | 
						
							| 54 | 51 53 | bitr3d |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( ( P .\/ Q ) = Q <-> P = Q ) ) | 
						
							| 55 | 49 54 | sylibd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( R = Q -> P = Q ) ) | 
						
							| 56 | 55 | necon3d |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( P =/= Q -> R =/= Q ) ) | 
						
							| 57 | 4 56 | mpd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> R =/= Q ) | 
						
							| 58 |  | simpl23 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> R e. A ) | 
						
							| 59 | 18 1 | atbase |  |-  ( R e. A -> R e. ( Base ` K ) ) | 
						
							| 60 | 58 59 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> R e. ( Base ` K ) ) | 
						
							| 61 | 18 2 3 | latlej1 |  |-  ( ( K e. Lat /\ Q e. ( Base ` K ) /\ R e. ( Base ` K ) ) -> Q .<_ ( Q .\/ R ) ) | 
						
							| 62 | 16 28 60 61 | syl3anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> Q .<_ ( Q .\/ R ) ) | 
						
							| 63 |  | simpr |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( P .\/ R ) = ( Q .\/ R ) ) | 
						
							| 64 | 62 63 | breqtrrd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> Q .<_ ( P .\/ R ) ) | 
						
							| 65 | 2 3 1 | cvlatexch1 |  |-  ( ( K e. CvLat /\ ( Q e. A /\ R e. A /\ P e. A ) /\ Q =/= P ) -> ( Q .<_ ( P .\/ R ) -> R .<_ ( P .\/ Q ) ) ) | 
						
							| 66 | 14 26 58 17 5 65 | syl131anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( Q .<_ ( P .\/ R ) -> R .<_ ( P .\/ Q ) ) ) | 
						
							| 67 | 64 66 | mpd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> R .<_ ( P .\/ Q ) ) | 
						
							| 68 | 38 57 67 | 3jca |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( P .\/ R ) = ( Q .\/ R ) ) -> ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) | 
						
							| 69 |  | simpr3 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> R .<_ ( P .\/ Q ) ) | 
						
							| 70 |  | simpl1 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> K e. CvLat ) | 
						
							| 71 | 70 15 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> K e. Lat ) | 
						
							| 72 |  | simpl21 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> P e. A ) | 
						
							| 73 | 72 19 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> P e. ( Base ` K ) ) | 
						
							| 74 |  | simpl22 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> Q e. A ) | 
						
							| 75 | 74 27 | syl |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> Q e. ( Base ` K ) ) | 
						
							| 76 | 18 3 | latjcom |  |-  ( ( K e. Lat /\ P e. ( Base ` K ) /\ Q e. ( Base ` K ) ) -> ( P .\/ Q ) = ( Q .\/ P ) ) | 
						
							| 77 | 71 73 75 76 | syl3anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> ( P .\/ Q ) = ( Q .\/ P ) ) | 
						
							| 78 | 77 | breq2d |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> ( R .<_ ( P .\/ Q ) <-> R .<_ ( Q .\/ P ) ) ) | 
						
							| 79 |  | simpl23 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> R e. A ) | 
						
							| 80 |  | simpr2 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> R =/= Q ) | 
						
							| 81 | 2 3 1 | cvlatexch1 |  |-  ( ( K e. CvLat /\ ( R e. A /\ P e. A /\ Q e. A ) /\ R =/= Q ) -> ( R .<_ ( Q .\/ P ) -> P .<_ ( Q .\/ R ) ) ) | 
						
							| 82 | 70 79 72 74 80 81 | syl131anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> ( R .<_ ( Q .\/ P ) -> P .<_ ( Q .\/ R ) ) ) | 
						
							| 83 |  | simpr1 |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> R =/= P ) | 
						
							| 84 | 83 | necomd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> P =/= R ) | 
						
							| 85 | 2 3 1 | cvlatexchb2 |  |-  ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= R ) -> ( P .<_ ( Q .\/ R ) <-> ( P .\/ R ) = ( Q .\/ R ) ) ) | 
						
							| 86 | 70 72 74 79 84 85 | syl131anc |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> ( P .<_ ( Q .\/ R ) <-> ( P .\/ R ) = ( Q .\/ R ) ) ) | 
						
							| 87 | 82 86 | sylibd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> ( R .<_ ( Q .\/ P ) -> ( P .\/ R ) = ( Q .\/ R ) ) ) | 
						
							| 88 | 78 87 | sylbid |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> ( R .<_ ( P .\/ Q ) -> ( P .\/ R ) = ( Q .\/ R ) ) ) | 
						
							| 89 | 69 88 | mpd |  |-  ( ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) /\ ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) -> ( P .\/ R ) = ( Q .\/ R ) ) | 
						
							| 90 | 68 89 | impbida |  |-  ( ( K e. CvLat /\ ( P e. A /\ Q e. A /\ R e. A ) /\ P =/= Q ) -> ( ( P .\/ R ) = ( Q .\/ R ) <-> ( R =/= P /\ R =/= Q /\ R .<_ ( P .\/ Q ) ) ) ) |