| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 3at.l |  |-  .<_ = ( le ` K ) | 
						
							| 2 |  | 3at.j |  |-  .\/ = ( join ` K ) | 
						
							| 3 |  | 3at.a |  |-  A = ( Atoms ` K ) | 
						
							| 4 |  | simp11 |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> K e. HL ) | 
						
							| 5 |  | simp12 |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> ( P e. A /\ Q e. A /\ R e. A ) ) | 
						
							| 6 |  | simp13l |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> S e. A ) | 
						
							| 7 |  | simp13r |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> T e. A ) | 
						
							| 8 |  | simp123 |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> R e. A ) | 
						
							| 9 | 6 7 8 | 3jca |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> ( S e. A /\ T e. A /\ R e. A ) ) | 
						
							| 10 |  | simp2l |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> -. R .<_ ( P .\/ Q ) ) | 
						
							| 11 | 4 | hllatd |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> K e. Lat ) | 
						
							| 12 |  | eqid |  |-  ( Base ` K ) = ( Base ` K ) | 
						
							| 13 | 12 3 | atbase |  |-  ( R e. A -> R e. ( Base ` K ) ) | 
						
							| 14 | 8 13 | syl |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> R e. ( Base ` K ) ) | 
						
							| 15 |  | simp121 |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> P e. A ) | 
						
							| 16 | 12 3 | atbase |  |-  ( P e. A -> P e. ( Base ` K ) ) | 
						
							| 17 | 15 16 | syl |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> P e. ( Base ` K ) ) | 
						
							| 18 |  | simp122 |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> Q e. A ) | 
						
							| 19 | 12 3 | atbase |  |-  ( Q e. A -> Q e. ( Base ` K ) ) | 
						
							| 20 | 18 19 | syl |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> Q e. ( Base ` K ) ) | 
						
							| 21 | 12 1 2 | latnlej1l |  |-  ( ( K e. Lat /\ ( R e. ( Base ` K ) /\ P e. ( Base ` K ) /\ Q e. ( Base ` K ) ) /\ -. R .<_ ( P .\/ Q ) ) -> R =/= P ) | 
						
							| 22 | 11 14 17 20 10 21 | syl131anc |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> R =/= P ) | 
						
							| 23 | 22 | necomd |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> P =/= R ) | 
						
							| 24 |  | simp2r |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> P =/= Q ) | 
						
							| 25 | 24 | necomd |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> Q =/= P ) | 
						
							| 26 | 1 2 3 | hlatexch1 |  |-  ( ( K e. HL /\ ( Q e. A /\ R e. A /\ P e. A ) /\ Q =/= P ) -> ( Q .<_ ( P .\/ R ) -> R .<_ ( P .\/ Q ) ) ) | 
						
							| 27 | 4 18 8 15 25 26 | syl131anc |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> ( Q .<_ ( P .\/ R ) -> R .<_ ( P .\/ Q ) ) ) | 
						
							| 28 | 10 27 | mtod |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> -. Q .<_ ( P .\/ R ) ) | 
						
							| 29 |  | simp3 |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) | 
						
							| 30 | 1 2 3 | 3atlem3 |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A /\ R e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= R /\ -. Q .<_ ( P .\/ R ) ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> ( ( P .\/ Q ) .\/ R ) = ( ( S .\/ T ) .\/ R ) ) | 
						
							| 31 | 4 5 9 10 23 28 29 30 | syl331anc |  |-  ( ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( S e. A /\ T e. A ) ) /\ ( -. R .<_ ( P .\/ Q ) /\ P =/= Q ) /\ ( ( P .\/ Q ) .\/ R ) .<_ ( ( S .\/ T ) .\/ R ) ) -> ( ( P .\/ Q ) .\/ R ) = ( ( S .\/ T ) .\/ R ) ) |