let X be OrtAfPl; :: thesis: ( X is satisfying_MH2 implies X is satisfying_OSCH )
assume A1: X is satisfying_MH2 ; :: thesis: X is satisfying_OSCH
let a1 be Element of X; :: according to CONMETR:def 7 :: thesis: for a2, a3, a4, b1, b2, b3, b4 being Element of X
for M, N being Subset of X st M _|_ N & a1 in M & a3 in M & b1 in M & b3 in M & a2 in N & a4 in N & b2 in N & b4 in N & not a4 in M & not a2 in M & not b2 in M & not b4 in M & not a1 in N & not a3 in N & not b1 in N & not b3 in N & a3,a2 // b3,b2 & a2,a1 // b2,b1 & a1,a4 // b1,b4 holds
a3,a4 // b3,b4

let a2, a3, a4, b1, b2, b3, b4 be Element of X; :: thesis: for M, N being Subset of X st M _|_ N & a1 in M & a3 in M & b1 in M & b3 in M & a2 in N & a4 in N & b2 in N & b4 in N & not a4 in M & not a2 in M & not b2 in M & not b4 in M & not a1 in N & not a3 in N & not b1 in N & not b3 in N & a3,a2 // b3,b2 & a2,a1 // b2,b1 & a1,a4 // b1,b4 holds
a3,a4 // b3,b4

let M, N be Subset of X; :: thesis: ( M _|_ N & a1 in M & a3 in M & b1 in M & b3 in M & a2 in N & a4 in N & b2 in N & b4 in N & not a4 in M & not a2 in M & not b2 in M & not b4 in M & not a1 in N & not a3 in N & not b1 in N & not b3 in N & a3,a2 // b3,b2 & a2,a1 // b2,b1 & a1,a4 // b1,b4 implies a3,a4 // b3,b4 )
assume that
A2: M _|_ N and
A3: a1 in M and
A4: a3 in M and
A5: b1 in M and
A6: b3 in M and
A7: a2 in N and
A8: a4 in N and
A9: b2 in N and
A10: b4 in N and
A11: not a4 in M and
A12: not a2 in M and
A13: not b2 in M and
A14: not b4 in M and
A15: not a1 in N and
A16: not a3 in N and
A17: not b1 in N and
not b3 in N and
A18: a3,a2 // b3,b2 and
A19: a2,a1 // b2,b1 and
A20: a1,a4 // b1,b4 ; :: thesis: a3,a4 // b3,b4
reconsider M9 = M, N9 = N as Subset of AffinStruct(# the carrier of X, the CONGR of X #) ;
N is being_line by A2, ANALMETR:44;
then A21: N9 is being_line by ANALMETR:43;
reconsider b49 = b4, b19 = b1, b29 = b2, b39 = b3, a19 = a1, a29 = a2, a39 = a3, a49 = a4 as Element of AffinStruct(# the carrier of X, the CONGR of X #) ;
M is being_line by A2, ANALMETR:44;
then A22: M9 is being_line by ANALMETR:43;
not M9 // N9
proof end;
then ex o9 being Element of AffinStruct(# the carrier of X, the CONGR of X #) st
( o9 in M9 & o9 in N9 ) by A22, A21, AFF_1:58;
then consider o being Element of X such that
A23: o in M and
A24: o in N ;
reconsider o9 = o as Element of AffinStruct(# the carrier of X, the CONGR of X #) ;
A25: now :: thesis: ( b2 <> b4 implies a3,a4 // b3,b4 )
assume A26: b2 <> b4 ; :: thesis: a3,a4 // b3,b4
A27: now :: thesis: ( b1 <> b3 implies a3,a4 // b3,b4 )
ex d39 being Element of AffinStruct(# the carrier of X, the CONGR of X #) st
( o9 <> d39 & d39 in N9 ) by A21, AFF_1:20;
then consider d3 being Element of X such that
A28: d3 in N and
A29: d3 <> o ;
reconsider d39 = d3 as Element of AffinStruct(# the carrier of X, the CONGR of X #) ;
consider e2 being Element of X such that
A30: a3,a2 _|_ d3,e2 and
A31: d3 <> e2 by ANALMETR:def 9;
consider e1 being Element of X such that
A32: a3,a1 // a3,e1 and
A33: a3 <> e1 by ANALMETR:39;
reconsider e19 = e1, e29 = e2 as Element of AffinStruct(# the carrier of X, the CONGR of X #) ;
assume A34: b1 <> b3 ; :: thesis: a3,a4 // b3,b4
A35: ( a1 <> a3 & a2 <> a4 )
proof
assume ( a1 = a3 or a2 = a4 ) ; :: thesis: contradiction
then ( a2,a1 // b3,b2 or a1,a4 // b2,b1 ) by A18, A19, ANALMETR:59;
then ( b3,b2 // b2,b1 or b2,b1 // b1,b4 ) by A3, A11, A12, A19, A20, ANALMETR:60;
then ( b2,b3 // b2,b1 or b1,b2 // b1,b4 ) by ANALMETR:59;
then ( LIN b2,b3,b1 or LIN b1,b2,b4 ) by ANALMETR:def 10;
then ( LIN b29,b39,b19 or LIN b19,b29,b49 ) by ANALMETR:40;
then ( LIN b19,b39,b29 or LIN b29,b49,b19 ) by AFF_1:6;
hence contradiction by A5, A6, A9, A10, A13, A17, A22, A21, A26, A34, AFF_1:25; :: thesis: verum
end;
not a39,e19 // d39,e29 then consider d29 being Element of AffinStruct(# the carrier of X, the CONGR of X #) such that
A37: LIN a39,e19,d29 and
A38: LIN d39,e29,d29 by AFF_1:60;
reconsider d2 = d29 as Element of X ;
LIN d3,e2,d2 by A38, ANALMETR:40;
then d3,e2 // d3,d2 by ANALMETR:def 10;
then A39: a3,a2 _|_ d3,d2 by A30, A31, ANALMETR:62;
LIN a3,e1,d2 by A37, ANALMETR:40;
then a3,e1 // a3,d2 by ANALMETR:def 10;
then a3,a1 // a3,d2 by A32, A33, ANALMETR:60;
then LIN a3,a1,d2 by ANALMETR:def 10;
then LIN a39,a19,d29 by ANALMETR:40;
then consider d2 being Element of X such that
A40: d2 in M and
A41: a3,a2 _|_ d3,d2 by A3, A4, A22, A35, A39, AFF_1:25;
reconsider d29 = d2 as Element of AffinStruct(# the carrier of X, the CONGR of X #) ;
consider e1 being Element of X such that
A42: a2,a4 // a2,e1 and
A43: a2 <> e1 by ANALMETR:39;
consider e2 being Element of X such that
A44: a2,a1 _|_ d2,e2 and
A45: d2 <> e2 by ANALMETR:def 9;
reconsider e19 = e1, e29 = e2 as Element of AffinStruct(# the carrier of X, the CONGR of X #) ;
not a29,e19 // d29,e29 then consider d19 being Element of AffinStruct(# the carrier of X, the CONGR of X #) such that
A47: LIN a29,e19,d19 and
A48: LIN d29,e29,d19 by AFF_1:60;
reconsider d1 = d19 as Element of X ;
A49: b3,b2 _|_ d3,d2 by A4, A12, A18, A41, ANALMETR:62;
LIN a2,e1,d1 by A47, ANALMETR:40;
then a2,e1 // a2,d1 by ANALMETR:def 10;
then a2,a4 // a2,d1 by A42, A43, ANALMETR:60;
then LIN a2,a4,d1 by ANALMETR:def 10;
then LIN a29,a49,d19 by ANALMETR:40;
then A50: d1 in N by A7, A8, A21, A35, AFF_1:25;
LIN d2,e2,d1 by A48, ANALMETR:40;
then d2,e2 // d2,d1 by ANALMETR:def 10;
then A51: a2,a1 _|_ d2,d1 by A44, A45, ANALMETR:62;
then A52: b2,b1 _|_ d2,d1 by A3, A12, A19, ANALMETR:62;
consider e2 being Element of X such that
A53: a1,a4 _|_ d1,e2 and
A54: d1 <> e2 by ANALMETR:39;
consider e1 being Element of X such that
A55: a1,a3 // a1,e1 and
A56: a1 <> e1 by ANALMETR:39;
reconsider e19 = e1, e29 = e2 as Element of AffinStruct(# the carrier of X, the CONGR of X #) ;
not a19,e19 // d19,e29 then consider d49 being Element of AffinStruct(# the carrier of X, the CONGR of X #) such that
A58: LIN a19,e19,d49 and
A59: LIN d19,e29,d49 by AFF_1:60;
reconsider d4 = d49 as Element of X ;
LIN a1,e1,d4 by A58, ANALMETR:40;
then a1,e1 // a1,d4 by ANALMETR:def 10;
then a1,a3 // a1,d4 by A55, A56, ANALMETR:60;
then LIN a1,a3,d4 by ANALMETR:def 10;
then LIN a19,a39,d49 by ANALMETR:40;
then A60: d4 in M by A3, A4, A22, A35, AFF_1:25;
then A61: d3 <> d4 by A2, A22, A21, A23, A24, A28, A29, AFF_1:18;
LIN d1,e2,d4 by A59, ANALMETR:40;
then d1,e2 // d1,d4 by ANALMETR:def 10;
then A62: a1,a4 _|_ d1,d4 by A53, A54, ANALMETR:62;
then b1,b4 _|_ d1,d4 by A3, A11, A20, ANALMETR:62;
then A63: b3,b4 _|_ d3,d4 by A1, A2, A5, A6, A9, A10, A13, A14, A28, A40, A50, A60, A49, A52;
a3,a4 _|_ d3,d4 by A1, A2, A3, A4, A7, A8, A11, A12, A28, A40, A41, A50, A51, A60, A62;
hence a3,a4 // b3,b4 by A63, A61, ANALMETR:63; :: thesis: verum
end;
now :: thesis: ( b1 = b3 implies a3,a4 // b3,b4 )end;
hence a3,a4 // b3,b4 by A27; :: thesis: verum
end;
now :: thesis: ( b2 = b4 implies a3,a4 // b3,b4 )end;
hence a3,a4 // b3,b4 by A25; :: thesis: verum