:: PBOOLE semantic presentation begin theorem :: PBOOLE:1 for f being Function st f is non-empty holds rng f is with_non-empty_elements ; theorem :: PBOOLE:2 for f being Function holds ( f is empty-yielding iff ( f = {} or rng f = {{}} ) ) proof let f be Function; ::_thesis: ( f is empty-yielding iff ( f = {} or rng f = {{}} ) ) hereby ::_thesis: ( ( f = {} or rng f = {{}} ) implies f is empty-yielding ) assume that A1: f is empty-yielding and A2: f <> {} ; ::_thesis: rng f = {{}} thus rng f = {{}} ::_thesis: verum proof hereby :: according to TARSKI:def_3,XBOOLE_0:def_10 ::_thesis: {{}} c= rng f let i be set ; ::_thesis: ( i in rng f implies i in {{}} ) assume i in rng f ; ::_thesis: i in {{}} then ex e being set st ( e in dom f & f . e = i ) by FUNCT_1:def_3; then i = {} by A1; hence i in {{}} by TARSKI:def_1; ::_thesis: verum end; set e = the Element of dom f; let i be set ; :: according to TARSKI:def_3 ::_thesis: ( not i in {{}} or i in rng f ) assume i in {{}} ; ::_thesis: i in rng f then A3: i = {} by TARSKI:def_1; A4: dom f <> {} by A2, RELAT_1:41; f . the Element of dom f is empty by A1; hence i in rng f by A4, A3, FUNCT_1:def_3; ::_thesis: verum end; end; assume A5: ( f = {} or rng f = {{}} ) ; ::_thesis: f is empty-yielding percases ( f = {} or rng f = {{}} ) by A5; suppose f = {} ; ::_thesis: f is empty-yielding hence for i being set st i in dom f holds f . i is empty by RELAT_1:38; :: according to FUNCT_1:def_8 ::_thesis: verum end; supposeA6: rng f = {{}} ; ::_thesis: f is empty-yielding let i be set ; :: according to FUNCT_1:def_8 ::_thesis: ( not i in dom f or f . i is empty ) assume i in dom f ; ::_thesis: f . i is empty then f . i in rng f by FUNCT_1:def_3; hence f . i is empty by A6, TARSKI:def_1; ::_thesis: verum end; end; end; registration let I be set ; cluster Relation-like I -defined Function-like total for set ; existence ex b1 being I -defined Function st b1 is total proof take I --> {} ; ::_thesis: I --> {} is total thus I --> {} is total ; ::_thesis: verum end; end; definition let I be set ; mode ManySortedSet of I is I -defined total Function; end; scheme :: PBOOLE:sch 1 KuratowskiFunction{ F1() -> set , F2( set ) -> set } : ex f being ManySortedSet of F1() st for e being set st e in F1() holds f . e in F2(e) provided A1: for e being set st e in F1() holds F2(e) <> {} proof defpred S1[ set , set ] means $2 in F2($1); A2: now__::_thesis:_for_e_being_set_st_e_in_F1()_holds_ ex_fe_being_set_st_S1[e,fe] let e be set ; ::_thesis: ( e in F1() implies ex fe being set st S1[e,fe] ) set fe = the Element of F2(e); assume A3: e in F1() ; ::_thesis: ex fe being set st S1[e,fe] reconsider fe = the Element of F2(e) as set ; take fe = fe; ::_thesis: S1[e,fe] F2(e) <> {} by A1, A3; hence S1[e,fe] ; ::_thesis: verum end; consider f being Function such that A4: dom f = F1() and A5: for e being set st e in F1() holds S1[e,f . e] from CLASSES1:sch_1(A2); reconsider f = f as ManySortedSet of F1() by A4, PARTFUN1:def_2, RELAT_1:def_18; take f ; ::_thesis: for e being set st e in F1() holds f . e in F2(e) thus for e being set st e in F1() holds f . e in F2(e) by A5; ::_thesis: verum end; definition let I be set ; let X, Y be ManySortedSet of I; predX in Y means :Def1: :: PBOOLE:def 1 for i being set st i in I holds X . i in Y . i; predX c= Y means :Def2: :: PBOOLE:def 2 for i being set st i in I holds X . i c= Y . i; reflexivity for X being ManySortedSet of I for i being set st i in I holds X . i c= X . i ; end; :: deftheorem Def1 defines in PBOOLE:def_1_:_ for I being set for X, Y being ManySortedSet of I holds ( X in Y iff for i being set st i in I holds X . i in Y . i ); :: deftheorem Def2 defines c= PBOOLE:def_2_:_ for I being set for X, Y being ManySortedSet of I holds ( X c= Y iff for i being set st i in I holds X . i c= Y . i ); definition let I be non empty set ; let X, Y be ManySortedSet of I; :: original: in redefine predX in Y; asymmetry for X, Y being ManySortedSet of I st (I,b1,b2) holds not (I,b2,b1) proof let X, Y be ManySortedSet of I; ::_thesis: ( (I,X,Y) implies not (I,Y,X) ) assume A1: for i being set st i in I holds X . i in Y . i ; :: according to PBOOLE:def_1 ::_thesis: (I,Y,X) ex i being set st ( i in I & not Y . i in X . i ) proof assume A2: for i being set st i in I holds Y . i in X . i ; ::_thesis: contradiction consider i being set such that A3: i in I by XBOOLE_0:def_1; X . i in Y . i by A1, A3; hence contradiction by A2, A3; ::_thesis: verum end; hence (I,Y,X) by Def1; ::_thesis: verum end; end; scheme :: PBOOLE:sch 2 PSeparation{ F1() -> set , F2() -> ManySortedSet of F1(), P1[ set , set ] } : ex X being ManySortedSet of F1() st for i being set st i in F1() holds for e being set holds ( e in X . i iff ( e in F2() . i & P1[i,e] ) ) proof defpred S1[ set , set ] means for e being set holds ( e in $2 iff ( e in F2() . $1 & P1[$1,e] ) ); A1: now__::_thesis:_for_i_being_set_st_i_in_F1()_holds_ ex_u_being_set_st_S1[i,u] let i be set ; ::_thesis: ( i in F1() implies ex u being set st S1[i,u] ) assume i in F1() ; ::_thesis: ex u being set st S1[i,u] defpred S2[ set ] means P1[i,$1]; ex u being set st for e being set holds ( e in u iff ( e in F2() . i & S2[e] ) ) from XBOOLE_0:sch_1(); hence ex u being set st S1[i,u] ; ::_thesis: verum end; consider f being Function such that A2: dom f = F1() and A3: for i being set st i in F1() holds S1[i,f . i] from CLASSES1:sch_1(A1); f is ManySortedSet of F1() by A2, PARTFUN1:def_2, RELAT_1:def_18; hence ex X being ManySortedSet of F1() st for i being set st i in F1() holds for e being set holds ( e in X . i iff ( e in F2() . i & P1[i,e] ) ) by A3; ::_thesis: verum end; theorem Th3: :: PBOOLE:3 for I being set for X, Y being ManySortedSet of I st ( for i being set st i in I holds X . i = Y . i ) holds X = Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st ( for i being set st i in I holds X . i = Y . i ) holds X = Y let X, Y be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds X . i = Y . i ) implies X = Y ) ( dom X = I & dom Y = I ) by PARTFUN1:def_2; hence ( ( for i being set st i in I holds X . i = Y . i ) implies X = Y ) by FUNCT_1:2; ::_thesis: verum end; definition let I be set ; func [[0]] I -> ManySortedSet of I equals :: PBOOLE:def 3 I --> {}; coherence I --> {} is ManySortedSet of I ; correctness ; let X, Y be ManySortedSet of I; funcX \/ Y -> ManySortedSet of I means :Def4: :: PBOOLE:def 4 for i being set st i in I holds it . i = (X . i) \/ (Y . i); existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = (X . i) \/ (Y . i) proof deffunc H1( set ) -> set = (X . $1) \/ (Y . $1); consider f being Function such that A1: dom f = I and A2: for i being set st i in I holds f . i = H1(i) from FUNCT_1:sch_3(); f is ManySortedSet of I by A1, PARTFUN1:def_2, RELAT_1:def_18; hence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = (X . i) \/ (Y . i) by A2; ::_thesis: verum end; uniqueness for b1, b2 being ManySortedSet of I st ( for i being set st i in I holds b1 . i = (X . i) \/ (Y . i) ) & ( for i being set st i in I holds b2 . i = (X . i) \/ (Y . i) ) holds b1 = b2 proof let A1, A2 be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds A1 . i = (X . i) \/ (Y . i) ) & ( for i being set st i in I holds A2 . i = (X . i) \/ (Y . i) ) implies A1 = A2 ) assume that A3: for i being set st i in I holds A1 . i = (X . i) \/ (Y . i) and A4: for i being set st i in I holds A2 . i = (X . i) \/ (Y . i) ; ::_thesis: A1 = A2 now__::_thesis:_for_i_being_set_st_i_in_I_holds_ A1_._i_=_A2_._i let i be set ; ::_thesis: ( i in I implies A1 . i = A2 . i ) assume A5: i in I ; ::_thesis: A1 . i = A2 . i hence A1 . i = (X . i) \/ (Y . i) by A3 .= A2 . i by A4, A5 ; ::_thesis: verum end; hence A1 = A2 by Th3; ::_thesis: verum end; commutativity for b1, X, Y being ManySortedSet of I st ( for i being set st i in I holds b1 . i = (X . i) \/ (Y . i) ) holds for i being set st i in I holds b1 . i = (Y . i) \/ (X . i) ; idempotence for X being ManySortedSet of I for i being set st i in I holds X . i = (X . i) \/ (X . i) ; funcX /\ Y -> ManySortedSet of I means :Def5: :: PBOOLE:def 5 for i being set st i in I holds it . i = (X . i) /\ (Y . i); existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = (X . i) /\ (Y . i) proof deffunc H1( set ) -> set = (X . $1) /\ (Y . $1); consider f being Function such that A6: dom f = I and A7: for i being set st i in I holds f . i = H1(i) from FUNCT_1:sch_3(); f is ManySortedSet of I by A6, PARTFUN1:def_2, RELAT_1:def_18; hence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = (X . i) /\ (Y . i) by A7; ::_thesis: verum end; uniqueness for b1, b2 being ManySortedSet of I st ( for i being set st i in I holds b1 . i = (X . i) /\ (Y . i) ) & ( for i being set st i in I holds b2 . i = (X . i) /\ (Y . i) ) holds b1 = b2 proof let A1, A2 be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds A1 . i = (X . i) /\ (Y . i) ) & ( for i being set st i in I holds A2 . i = (X . i) /\ (Y . i) ) implies A1 = A2 ) assume that A8: for i being set st i in I holds A1 . i = (X . i) /\ (Y . i) and A9: for i being set st i in I holds A2 . i = (X . i) /\ (Y . i) ; ::_thesis: A1 = A2 now__::_thesis:_for_i_being_set_st_i_in_I_holds_ A1_._i_=_A2_._i let i be set ; ::_thesis: ( i in I implies A1 . i = A2 . i ) assume A10: i in I ; ::_thesis: A1 . i = A2 . i hence A1 . i = (X . i) /\ (Y . i) by A8 .= A2 . i by A9, A10 ; ::_thesis: verum end; hence A1 = A2 by Th3; ::_thesis: verum end; commutativity for b1, X, Y being ManySortedSet of I st ( for i being set st i in I holds b1 . i = (X . i) /\ (Y . i) ) holds for i being set st i in I holds b1 . i = (Y . i) /\ (X . i) ; idempotence for X being ManySortedSet of I for i being set st i in I holds X . i = (X . i) /\ (X . i) ; funcX \ Y -> ManySortedSet of I means :Def6: :: PBOOLE:def 6 for i being set st i in I holds it . i = (X . i) \ (Y . i); existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = (X . i) \ (Y . i) proof deffunc H1( set ) -> Element of bool (X . $1) = (X . $1) \ (Y . $1); consider f being Function such that A11: dom f = I and A12: for i being set st i in I holds f . i = H1(i) from FUNCT_1:sch_3(); f is ManySortedSet of I by A11, PARTFUN1:def_2, RELAT_1:def_18; hence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = (X . i) \ (Y . i) by A12; ::_thesis: verum end; uniqueness for b1, b2 being ManySortedSet of I st ( for i being set st i in I holds b1 . i = (X . i) \ (Y . i) ) & ( for i being set st i in I holds b2 . i = (X . i) \ (Y . i) ) holds b1 = b2 proof let A1, A2 be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds A1 . i = (X . i) \ (Y . i) ) & ( for i being set st i in I holds A2 . i = (X . i) \ (Y . i) ) implies A1 = A2 ) assume that A13: for i being set st i in I holds A1 . i = (X . i) \ (Y . i) and A14: for i being set st i in I holds A2 . i = (X . i) \ (Y . i) ; ::_thesis: A1 = A2 now__::_thesis:_for_i_being_set_st_i_in_I_holds_ A1_._i_=_A2_._i let i be set ; ::_thesis: ( i in I implies A1 . i = A2 . i ) assume A15: i in I ; ::_thesis: A1 . i = A2 . i hence A1 . i = (X . i) \ (Y . i) by A13 .= A2 . i by A14, A15 ; ::_thesis: verum end; hence A1 = A2 by Th3; ::_thesis: verum end; predX overlaps Y means :Def7: :: PBOOLE:def 7 for i being set st i in I holds X . i meets Y . i; symmetry for X, Y being ManySortedSet of I st ( for i being set st i in I holds X . i meets Y . i ) holds for i being set st i in I holds Y . i meets X . i ; predX misses Y means :Def8: :: PBOOLE:def 8 for i being set st i in I holds X . i misses Y . i; symmetry for X, Y being ManySortedSet of I st ( for i being set st i in I holds X . i misses Y . i ) holds for i being set st i in I holds Y . i misses X . i ; end; :: deftheorem defines [[0]] PBOOLE:def_3_:_ for I being set holds [[0]] I = I --> {}; :: deftheorem Def4 defines \/ PBOOLE:def_4_:_ for I being set for X, Y, b4 being ManySortedSet of I holds ( b4 = X \/ Y iff for i being set st i in I holds b4 . i = (X . i) \/ (Y . i) ); :: deftheorem Def5 defines /\ PBOOLE:def_5_:_ for I being set for X, Y, b4 being ManySortedSet of I holds ( b4 = X /\ Y iff for i being set st i in I holds b4 . i = (X . i) /\ (Y . i) ); :: deftheorem Def6 defines \ PBOOLE:def_6_:_ for I being set for X, Y, b4 being ManySortedSet of I holds ( b4 = X \ Y iff for i being set st i in I holds b4 . i = (X . i) \ (Y . i) ); :: deftheorem Def7 defines overlaps PBOOLE:def_7_:_ for I being set for X, Y being ManySortedSet of I holds ( X overlaps Y iff for i being set st i in I holds X . i meets Y . i ); :: deftheorem Def8 defines misses PBOOLE:def_8_:_ for I being set for X, Y being ManySortedSet of I holds ( X misses Y iff for i being set st i in I holds X . i misses Y . i ); notation let I be set ; let X, Y be ManySortedSet of I; antonym X meets Y for X misses Y; end; definition let I be set ; let X, Y be ManySortedSet of I; funcX \+\ Y -> ManySortedSet of I equals :: PBOOLE:def 9 (X \ Y) \/ (Y \ X); correctness coherence (X \ Y) \/ (Y \ X) is ManySortedSet of I; ; commutativity for b1, X, Y being ManySortedSet of I st b1 = (X \ Y) \/ (Y \ X) holds b1 = (Y \ X) \/ (X \ Y) ; end; :: deftheorem defines \+\ PBOOLE:def_9_:_ for I being set for X, Y being ManySortedSet of I holds X \+\ Y = (X \ Y) \/ (Y \ X); theorem Th4: :: PBOOLE:4 for I being set for X, Y being ManySortedSet of I for i being set st i in I holds (X \+\ Y) . i = (X . i) \+\ (Y . i) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I for i being set st i in I holds (X \+\ Y) . i = (X . i) \+\ (Y . i) let X, Y be ManySortedSet of I; ::_thesis: for i being set st i in I holds (X \+\ Y) . i = (X . i) \+\ (Y . i) let i be set ; ::_thesis: ( i in I implies (X \+\ Y) . i = (X . i) \+\ (Y . i) ) assume A1: i in I ; ::_thesis: (X \+\ Y) . i = (X . i) \+\ (Y . i) thus (X \+\ Y) . i = ((X \ Y) . i) \/ ((Y \ X) . i) by A1, Def4 .= ((X . i) \ (Y . i)) \/ ((Y \ X) . i) by A1, Def6 .= (X . i) \+\ (Y . i) by A1, Def6 ; ::_thesis: verum end; theorem Th5: :: PBOOLE:5 for i, I being set holds ([[0]] I) . i = {} proof let i, I be set ; ::_thesis: ([[0]] I) . i = {} percases ( i in I or not i in I ) ; suppose i in I ; ::_thesis: ([[0]] I) . i = {} hence ([[0]] I) . i = {} by FUNCOP_1:7; ::_thesis: verum end; suppose not i in I ; ::_thesis: ([[0]] I) . i = {} then not i in dom ([[0]] I) by FUNCOP_1:13; hence ([[0]] I) . i = {} by FUNCT_1:def_2; ::_thesis: verum end; end; end; theorem Th6: :: PBOOLE:6 for I being set for X being ManySortedSet of I st ( for i being set st i in I holds X . i = {} ) holds X = [[0]] I proof let I be set ; ::_thesis: for X being ManySortedSet of I st ( for i being set st i in I holds X . i = {} ) holds X = [[0]] I let X be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds X . i = {} ) implies X = [[0]] I ) assume A1: for i being set st i in I holds X . i = {} ; ::_thesis: X = [[0]] I now__::_thesis:_for_i_being_set_st_i_in_I_holds_ X_._i_=_([[0]]_I)_._i let i be set ; ::_thesis: ( i in I implies X . i = ([[0]] I) . i ) assume i in I ; ::_thesis: X . i = ([[0]] I) . i hence X . i = {} by A1 .= ([[0]] I) . i by Th5 ; ::_thesis: verum end; hence X = [[0]] I by Th3; ::_thesis: verum end; theorem Th7: :: PBOOLE:7 for I being set for x, X, Y being ManySortedSet of I st ( x in X or x in Y ) holds x in X \/ Y proof let I be set ; ::_thesis: for x, X, Y being ManySortedSet of I st ( x in X or x in Y ) holds x in X \/ Y let x, X, Y be ManySortedSet of I; ::_thesis: ( ( x in X or x in Y ) implies x in X \/ Y ) assume A1: ( x in X or x in Y ) ; ::_thesis: x in X \/ Y let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies x . i in (X \/ Y) . i ) assume A2: i in I ; ::_thesis: x . i in (X \/ Y) . i then ( x . i in X . i or x . i in Y . i ) by A1, Def1; then x . i in (X . i) \/ (Y . i) by XBOOLE_0:def_3; hence x . i in (X \/ Y) . i by A2, Def4; ::_thesis: verum end; theorem Th8: :: PBOOLE:8 for I being set for x, X, Y being ManySortedSet of I holds ( x in X /\ Y iff ( x in X & x in Y ) ) proof let I be set ; ::_thesis: for x, X, Y being ManySortedSet of I holds ( x in X /\ Y iff ( x in X & x in Y ) ) let x, X, Y be ManySortedSet of I; ::_thesis: ( x in X /\ Y iff ( x in X & x in Y ) ) hereby ::_thesis: ( x in X & x in Y implies x in X /\ Y ) assume A1: x in X /\ Y ; ::_thesis: ( x in X & x in Y ) thus x in X ::_thesis: x in Y proof let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies x . i in X . i ) assume A2: i in I ; ::_thesis: x . i in X . i then x . i in (X /\ Y) . i by A1, Def1; then x . i in (X . i) /\ (Y . i) by A2, Def5; hence x . i in X . i by XBOOLE_0:def_4; ::_thesis: verum end; thus x in Y ::_thesis: verum proof let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies x . i in Y . i ) assume A3: i in I ; ::_thesis: x . i in Y . i then x . i in (X /\ Y) . i by A1, Def1; then x . i in (X . i) /\ (Y . i) by A3, Def5; hence x . i in Y . i by XBOOLE_0:def_4; ::_thesis: verum end; end; assume A4: ( x in X & x in Y ) ; ::_thesis: x in X /\ Y let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies x . i in (X /\ Y) . i ) assume A5: i in I ; ::_thesis: x . i in (X /\ Y) . i then ( x . i in X . i & x . i in Y . i ) by A4, Def1; then x . i in (X . i) /\ (Y . i) by XBOOLE_0:def_4; hence x . i in (X /\ Y) . i by A5, Def5; ::_thesis: verum end; theorem Th9: :: PBOOLE:9 for I being set for x, X, Y being ManySortedSet of I st x in X & X c= Y holds x in Y proof let I be set ; ::_thesis: for x, X, Y being ManySortedSet of I st x in X & X c= Y holds x in Y let x, X, Y be ManySortedSet of I; ::_thesis: ( x in X & X c= Y implies x in Y ) assume A1: ( x in X & X c= Y ) ; ::_thesis: x in Y let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies x . i in Y . i ) assume i in I ; ::_thesis: x . i in Y . i then ( x . i in X . i & X . i c= Y . i ) by A1, Def1, Def2; hence x . i in Y . i ; ::_thesis: verum end; theorem Th10: :: PBOOLE:10 for I being set for x, X, Y being ManySortedSet of I st x in X & x in Y holds X overlaps Y proof let I be set ; ::_thesis: for x, X, Y being ManySortedSet of I st x in X & x in Y holds X overlaps Y let x, X, Y be ManySortedSet of I; ::_thesis: ( x in X & x in Y implies X overlaps Y ) assume A1: ( x in X & x in Y ) ; ::_thesis: X overlaps Y let i be set ; :: according to PBOOLE:def_7 ::_thesis: ( i in I implies X . i meets Y . i ) assume i in I ; ::_thesis: X . i meets Y . i then ( x . i in X . i & x . i in Y . i ) by A1, Def1; hence X . i meets Y . i by XBOOLE_0:3; ::_thesis: verum end; theorem Th11: :: PBOOLE:11 for I being set for X, Y being ManySortedSet of I st X overlaps Y holds ex x being ManySortedSet of I st ( x in X & x in Y ) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X overlaps Y holds ex x being ManySortedSet of I st ( x in X & x in Y ) let X, Y be ManySortedSet of I; ::_thesis: ( X overlaps Y implies ex x being ManySortedSet of I st ( x in X & x in Y ) ) deffunc H1( set ) -> set = (X . $1) /\ (Y . $1); assume A1: X overlaps Y ; ::_thesis: ex x being ManySortedSet of I st ( x in X & x in Y ) A2: now__::_thesis:_for_i_being_set_st_i_in_I_holds_ H1(i)_<>_{} let i be set ; ::_thesis: ( i in I implies H1(i) <> {} ) assume i in I ; ::_thesis: H1(i) <> {} then X . i meets Y . i by A1, Def7; hence H1(i) <> {} by XBOOLE_0:def_7; ::_thesis: verum end; consider x being ManySortedSet of I such that A3: for i being set st i in I holds x . i in H1(i) from PBOOLE:sch_1(A2); take x ; ::_thesis: ( x in X & x in Y ) now__::_thesis:_for_i_being_set_st_i_in_I_holds_ x_._i_in_X_._i let i be set ; ::_thesis: ( i in I implies x . i in X . i ) assume i in I ; ::_thesis: x . i in X . i then x . i in (X . i) /\ (Y . i) by A3; hence x . i in X . i by XBOOLE_0:def_4; ::_thesis: verum end; hence x in X by Def1; ::_thesis: x in Y now__::_thesis:_for_i_being_set_st_i_in_I_holds_ x_._i_in_Y_._i let i be set ; ::_thesis: ( i in I implies x . i in Y . i ) assume i in I ; ::_thesis: x . i in Y . i then x . i in (X . i) /\ (Y . i) by A3; hence x . i in Y . i by XBOOLE_0:def_4; ::_thesis: verum end; hence x in Y by Def1; ::_thesis: verum end; theorem :: PBOOLE:12 for I being set for x, X, Y being ManySortedSet of I st x in X \ Y holds x in X proof let I be set ; ::_thesis: for x, X, Y being ManySortedSet of I st x in X \ Y holds x in X let x, X, Y be ManySortedSet of I; ::_thesis: ( x in X \ Y implies x in X ) assume A1: x in X \ Y ; ::_thesis: x in X thus x in X ::_thesis: verum proof let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies x . i in X . i ) assume A2: i in I ; ::_thesis: x . i in X . i then x . i in (X \ Y) . i by A1, Def1; then x . i in (X . i) \ (Y . i) by A2, Def6; hence x . i in X . i ; ::_thesis: verum end; end; begin Lm1: for I being set for X, Y being ManySortedSet of I st X c= Y & Y c= X holds X = Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X c= Y & Y c= X holds X = Y let X, Y be ManySortedSet of I; ::_thesis: ( X c= Y & Y c= X implies X = Y ) assume A1: ( X c= Y & Y c= X ) ; ::_thesis: X = Y now__::_thesis:_for_i_being_set_st_i_in_I_holds_ X_._i_=_Y_._i let i be set ; ::_thesis: ( i in I implies X . i = Y . i ) assume i in I ; ::_thesis: X . i = Y . i then ( X . i c= Y . i & Y . i c= X . i ) by A1, Def2; hence X . i = Y . i by XBOOLE_0:def_10; ::_thesis: verum end; hence X = Y by Th3; ::_thesis: verum end; definition let I be set ; let X, Y be ManySortedSet of I; :: original: = redefine predX = Y means :: PBOOLE:def 10 for i being set st i in I holds X . i = Y . i; compatibility ( X = Y iff for i being set st i in I holds X . i = Y . i ) by Th3; end; :: deftheorem defines = PBOOLE:def_10_:_ for I being set for X, Y being ManySortedSet of I holds ( X = Y iff for i being set st i in I holds X . i = Y . i ); theorem Th13: :: PBOOLE:13 for I being set for X, Y, Z being ManySortedSet of I st X c= Y & Y c= Z holds X c= Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y & Y c= Z holds X c= Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y & Y c= Z implies X c= Z ) assume that A1: X c= Y and A2: Y c= Z ; ::_thesis: X c= Z let i be set ; :: according to PBOOLE:def_2 ::_thesis: ( i in I implies X . i c= Z . i ) assume A3: i in I ; ::_thesis: X . i c= Z . i let e be set ; :: according to TARSKI:def_3 ::_thesis: ( not e in X . i or e in Z . i ) assume A4: e in X . i ; ::_thesis: e in Z . i X . i c= Y . i by A1, A3, Def2; then A5: e in Y . i by A4; Y . i c= Z . i by A2, A3, Def2; hence e in Z . i by A5; ::_thesis: verum end; theorem Th14: :: PBOOLE:14 for I being set for X, Y being ManySortedSet of I holds X c= X \/ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X c= X \/ Y let X, Y be ManySortedSet of I; ::_thesis: X c= X \/ Y let i be set ; :: according to PBOOLE:def_2 ::_thesis: ( i in I implies X . i c= (X \/ Y) . i ) assume A1: i in I ; ::_thesis: X . i c= (X \/ Y) . i let e be set ; :: according to TARSKI:def_3 ::_thesis: ( not e in X . i or e in (X \/ Y) . i ) assume e in X . i ; ::_thesis: e in (X \/ Y) . i then e in (X . i) \/ (Y . i) by XBOOLE_0:def_3; hence e in (X \/ Y) . i by A1, Def4; ::_thesis: verum end; theorem Th15: :: PBOOLE:15 for I being set for X, Y being ManySortedSet of I holds X /\ Y c= X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X /\ Y c= X let X, Y be ManySortedSet of I; ::_thesis: X /\ Y c= X let i be set ; :: according to PBOOLE:def_2 ::_thesis: ( i in I implies (X /\ Y) . i c= X . i ) assume A1: i in I ; ::_thesis: (X /\ Y) . i c= X . i let e be set ; :: according to TARSKI:def_3 ::_thesis: ( not e in (X /\ Y) . i or e in X . i ) assume e in (X /\ Y) . i ; ::_thesis: e in X . i then e in (X . i) /\ (Y . i) by A1, Def5; hence e in X . i by XBOOLE_0:def_4; ::_thesis: verum end; theorem Th16: :: PBOOLE:16 for I being set for X, Z, Y being ManySortedSet of I st X c= Z & Y c= Z holds X \/ Y c= Z proof let I be set ; ::_thesis: for X, Z, Y being ManySortedSet of I st X c= Z & Y c= Z holds X \/ Y c= Z let X, Z, Y be ManySortedSet of I; ::_thesis: ( X c= Z & Y c= Z implies X \/ Y c= Z ) assume A1: ( X c= Z & Y c= Z ) ; ::_thesis: X \/ Y c= Z let i be set ; :: according to PBOOLE:def_2 ::_thesis: ( i in I implies (X \/ Y) . i c= Z . i ) assume A2: i in I ; ::_thesis: (X \/ Y) . i c= Z . i then ( X . i c= Z . i & Y . i c= Z . i ) by A1, Def2; then (X . i) \/ (Y . i) c= Z . i by XBOOLE_1:8; hence (X \/ Y) . i c= Z . i by A2, Def4; ::_thesis: verum end; theorem Th17: :: PBOOLE:17 for I being set for Z, X, Y being ManySortedSet of I st Z c= X & Z c= Y holds Z c= X /\ Y proof let I be set ; ::_thesis: for Z, X, Y being ManySortedSet of I st Z c= X & Z c= Y holds Z c= X /\ Y let Z, X, Y be ManySortedSet of I; ::_thesis: ( Z c= X & Z c= Y implies Z c= X /\ Y ) assume A1: ( Z c= X & Z c= Y ) ; ::_thesis: Z c= X /\ Y let i be set ; :: according to PBOOLE:def_2 ::_thesis: ( i in I implies Z . i c= (X /\ Y) . i ) assume A2: i in I ; ::_thesis: Z . i c= (X /\ Y) . i then ( Z . i c= X . i & Z . i c= Y . i ) by A1, Def2; then Z . i c= (X . i) /\ (Y . i) by XBOOLE_1:19; hence Z . i c= (X /\ Y) . i by A2, Def5; ::_thesis: verum end; theorem :: PBOOLE:18 for I being set for X, Y, Z being ManySortedSet of I st X c= Y holds X \/ Z c= Y \/ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y holds X \/ Z c= Y \/ Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y implies X \/ Z c= Y \/ Z ) assume A1: X c= Y ; ::_thesis: X \/ Z c= Y \/ Z A2: Z c= Y \/ Z by Th14; Y c= Y \/ Z by Th14; then X c= Y \/ Z by A1, Th13; hence X \/ Z c= Y \/ Z by A2, Th16; ::_thesis: verum end; theorem Th19: :: PBOOLE:19 for I being set for X, Y, Z being ManySortedSet of I st X c= Y holds X /\ Z c= Y /\ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y holds X /\ Z c= Y /\ Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y implies X /\ Z c= Y /\ Z ) assume A1: X c= Y ; ::_thesis: X /\ Z c= Y /\ Z A2: X /\ Z c= Z by Th15; X /\ Z c= X by Th15; then X /\ Z c= Y by A1, Th13; hence X /\ Z c= Y /\ Z by A2, Th17; ::_thesis: verum end; theorem Th20: :: PBOOLE:20 for I being set for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V holds X \/ Z c= Y \/ V proof let I be set ; ::_thesis: for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V holds X \/ Z c= Y \/ V let X, Y, Z, V be ManySortedSet of I; ::_thesis: ( X c= Y & Z c= V implies X \/ Z c= Y \/ V ) assume that A1: X c= Y and A2: Z c= V ; ::_thesis: X \/ Z c= Y \/ V V c= Y \/ V by Th14; then A3: Z c= Y \/ V by A2, Th13; Y c= Y \/ V by Th14; then X c= Y \/ V by A1, Th13; hence X \/ Z c= Y \/ V by A3, Th16; ::_thesis: verum end; theorem :: PBOOLE:21 for I being set for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V holds X /\ Z c= Y /\ V proof let I be set ; ::_thesis: for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V holds X /\ Z c= Y /\ V let X, Y, Z, V be ManySortedSet of I; ::_thesis: ( X c= Y & Z c= V implies X /\ Z c= Y /\ V ) assume that A1: X c= Y and A2: Z c= V ; ::_thesis: X /\ Z c= Y /\ V X /\ Z c= Z by Th15; then A3: X /\ Z c= V by A2, Th13; X /\ Z c= X by Th15; then X /\ Z c= Y by A1, Th13; hence X /\ Z c= Y /\ V by A3, Th17; ::_thesis: verum end; theorem Th22: :: PBOOLE:22 for I being set for X, Y being ManySortedSet of I st X c= Y holds X \/ Y = Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X c= Y holds X \/ Y = Y let X, Y be ManySortedSet of I; ::_thesis: ( X c= Y implies X \/ Y = Y ) assume X c= Y ; ::_thesis: X \/ Y = Y then A1: X \/ Y c= Y by Th16; Y c= X \/ Y by Th14; hence X \/ Y = Y by A1, Lm1; ::_thesis: verum end; theorem Th23: :: PBOOLE:23 for I being set for X, Y being ManySortedSet of I st X c= Y holds X /\ Y = X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X c= Y holds X /\ Y = X let X, Y be ManySortedSet of I; ::_thesis: ( X c= Y implies X /\ Y = X ) assume A1: X c= Y ; ::_thesis: X /\ Y = X A2: X /\ Y c= X by Th15; X c= X /\ Y by A1, Th17; hence X /\ Y = X by A2, Lm1; ::_thesis: verum end; theorem :: PBOOLE:24 for I being set for X, Y, Z being ManySortedSet of I holds X /\ Y c= X \/ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X /\ Y c= X \/ Z let X, Y, Z be ManySortedSet of I; ::_thesis: X /\ Y c= X \/ Z ( X /\ Y c= X & X c= X \/ Z ) by Th14, Th15; hence X /\ Y c= X \/ Z by Th13; ::_thesis: verum end; theorem :: PBOOLE:25 for I being set for X, Z, Y being ManySortedSet of I st X c= Z holds X \/ (Y /\ Z) = (X \/ Y) /\ Z proof let I be set ; ::_thesis: for X, Z, Y being ManySortedSet of I st X c= Z holds X \/ (Y /\ Z) = (X \/ Y) /\ Z let X, Z, Y be ManySortedSet of I; ::_thesis: ( X c= Z implies X \/ (Y /\ Z) = (X \/ Y) /\ Z ) assume A1: X c= Z ; ::_thesis: X \/ (Y /\ Z) = (X \/ Y) /\ Z let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies (X \/ (Y /\ Z)) . i = ((X \/ Y) /\ Z) . i ) assume A2: i in I ; ::_thesis: (X \/ (Y /\ Z)) . i = ((X \/ Y) /\ Z) . i then A3: X . i c= Z . i by A1, Def2; thus (X \/ (Y /\ Z)) . i = (X . i) \/ ((Y /\ Z) . i) by A2, Def4 .= (X . i) \/ ((Y . i) /\ (Z . i)) by A2, Def5 .= ((X . i) \/ (Y . i)) /\ (Z . i) by A3, XBOOLE_1:30 .= ((X \/ Y) . i) /\ (Z . i) by A2, Def4 .= ((X \/ Y) /\ Z) . i by A2, Def5 ; ::_thesis: verum end; theorem :: PBOOLE:26 for I being set for X, Y, Z being ManySortedSet of I holds ( X = Y \/ Z iff ( Y c= X & Z c= X & ( for V being ManySortedSet of I st Y c= V & Z c= V holds X c= V ) ) ) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds ( X = Y \/ Z iff ( Y c= X & Z c= X & ( for V being ManySortedSet of I st Y c= V & Z c= V holds X c= V ) ) ) let X, Y, Z be ManySortedSet of I; ::_thesis: ( X = Y \/ Z iff ( Y c= X & Z c= X & ( for V being ManySortedSet of I st Y c= V & Z c= V holds X c= V ) ) ) thus ( X = Y \/ Z implies ( Y c= X & Z c= X & ( for V being ManySortedSet of I st Y c= V & Z c= V holds X c= V ) ) ) by Th14, Th16; ::_thesis: ( Y c= X & Z c= X & ( for V being ManySortedSet of I st Y c= V & Z c= V holds X c= V ) implies X = Y \/ Z ) assume that A1: ( Y c= X & Z c= X ) and A2: for V being ManySortedSet of I st Y c= V & Z c= V holds X c= V ; ::_thesis: X = Y \/ Z ( Y c= Y \/ Z & Z c= Y \/ Z ) by Th14; then A3: X c= Y \/ Z by A2; Y \/ Z c= X by A1, Th16; hence X = Y \/ Z by A3, Lm1; ::_thesis: verum end; theorem :: PBOOLE:27 for I being set for X, Y, Z being ManySortedSet of I holds ( X = Y /\ Z iff ( X c= Y & X c= Z & ( for V being ManySortedSet of I st V c= Y & V c= Z holds V c= X ) ) ) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds ( X = Y /\ Z iff ( X c= Y & X c= Z & ( for V being ManySortedSet of I st V c= Y & V c= Z holds V c= X ) ) ) let X, Y, Z be ManySortedSet of I; ::_thesis: ( X = Y /\ Z iff ( X c= Y & X c= Z & ( for V being ManySortedSet of I st V c= Y & V c= Z holds V c= X ) ) ) thus ( X = Y /\ Z implies ( X c= Y & X c= Z & ( for V being ManySortedSet of I st V c= Y & V c= Z holds V c= X ) ) ) by Th15, Th17; ::_thesis: ( X c= Y & X c= Z & ( for V being ManySortedSet of I st V c= Y & V c= Z holds V c= X ) implies X = Y /\ Z ) assume that A1: ( X c= Y & X c= Z ) and A2: for V being ManySortedSet of I st V c= Y & V c= Z holds V c= X ; ::_thesis: X = Y /\ Z A3: X c= Y /\ Z by A1, Th17; ( Y /\ Z c= Y & Y /\ Z c= Z implies Y /\ Z c= X ) by A2; hence X = Y /\ Z by A3, Lm1, Th15; ::_thesis: verum end; theorem Th28: :: PBOOLE:28 for I being set for X, Y, Z being ManySortedSet of I holds (X \/ Y) \/ Z = X \/ (Y \/ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X \/ Y) \/ Z = X \/ (Y \/ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X \/ Y) \/ Z = X \/ (Y \/ Z) let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies ((X \/ Y) \/ Z) . i = (X \/ (Y \/ Z)) . i ) assume A1: i in I ; ::_thesis: ((X \/ Y) \/ Z) . i = (X \/ (Y \/ Z)) . i hence ((X \/ Y) \/ Z) . i = ((X \/ Y) . i) \/ (Z . i) by Def4 .= ((X . i) \/ (Y . i)) \/ (Z . i) by A1, Def4 .= (X . i) \/ ((Y . i) \/ (Z . i)) by XBOOLE_1:4 .= (X . i) \/ ((Y \/ Z) . i) by A1, Def4 .= (X \/ (Y \/ Z)) . i by A1, Def4 ; ::_thesis: verum end; theorem Th29: :: PBOOLE:29 for I being set for X, Y, Z being ManySortedSet of I holds (X /\ Y) /\ Z = X /\ (Y /\ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X /\ Y) /\ Z = X /\ (Y /\ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X /\ Y) /\ Z = X /\ (Y /\ Z) let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies ((X /\ Y) /\ Z) . i = (X /\ (Y /\ Z)) . i ) assume A1: i in I ; ::_thesis: ((X /\ Y) /\ Z) . i = (X /\ (Y /\ Z)) . i hence ((X /\ Y) /\ Z) . i = ((X /\ Y) . i) /\ (Z . i) by Def5 .= ((X . i) /\ (Y . i)) /\ (Z . i) by A1, Def5 .= (X . i) /\ ((Y . i) /\ (Z . i)) by XBOOLE_1:16 .= (X . i) /\ ((Y /\ Z) . i) by A1, Def5 .= (X /\ (Y /\ Z)) . i by A1, Def5 ; ::_thesis: verum end; theorem Th30: :: PBOOLE:30 for I being set for X, Y being ManySortedSet of I holds X /\ (X \/ Y) = X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X /\ (X \/ Y) = X let X, Y be ManySortedSet of I; ::_thesis: X /\ (X \/ Y) = X X c= X \/ Y by Th14; then A1: X c= X /\ (X \/ Y) by Th17; X /\ (X \/ Y) c= X by Th15; hence X /\ (X \/ Y) = X by A1, Lm1; ::_thesis: verum end; theorem Th31: :: PBOOLE:31 for I being set for X, Y being ManySortedSet of I holds X \/ (X /\ Y) = X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \/ (X /\ Y) = X let X, Y be ManySortedSet of I; ::_thesis: X \/ (X /\ Y) = X X /\ Y c= X by Th15; then A1: X \/ (X /\ Y) c= X by Th16; X c= X \/ (X /\ Y) by Th14; hence X \/ (X /\ Y) = X by A1, Lm1; ::_thesis: verum end; theorem Th32: :: PBOOLE:32 for I being set for X, Y, Z being ManySortedSet of I holds X /\ (Y \/ Z) = (X /\ Y) \/ (X /\ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X /\ (Y \/ Z) = (X /\ Y) \/ (X /\ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: X /\ (Y \/ Z) = (X /\ Y) \/ (X /\ Z) let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies (X /\ (Y \/ Z)) . i = ((X /\ Y) \/ (X /\ Z)) . i ) assume A1: i in I ; ::_thesis: (X /\ (Y \/ Z)) . i = ((X /\ Y) \/ (X /\ Z)) . i hence (X /\ (Y \/ Z)) . i = (X . i) /\ ((Y \/ Z) . i) by Def5 .= (X . i) /\ ((Y . i) \/ (Z . i)) by A1, Def4 .= ((X . i) /\ (Y . i)) \/ ((X . i) /\ (Z . i)) by XBOOLE_1:23 .= ((X /\ Y) . i) \/ ((X . i) /\ (Z . i)) by A1, Def5 .= ((X /\ Y) . i) \/ ((X /\ Z) . i) by A1, Def5 .= ((X /\ Y) \/ (X /\ Z)) . i by A1, Def4 ; ::_thesis: verum end; theorem Th33: :: PBOOLE:33 for I being set for X, Y, Z being ManySortedSet of I holds X \/ (Y /\ Z) = (X \/ Y) /\ (X \/ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X \/ (Y /\ Z) = (X \/ Y) /\ (X \/ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: X \/ (Y /\ Z) = (X \/ Y) /\ (X \/ Z) thus X \/ (Y /\ Z) = (X \/ (X /\ Z)) \/ (Y /\ Z) by Th31 .= X \/ ((X /\ Z) \/ (Y /\ Z)) by Th28 .= X \/ ((X \/ Y) /\ Z) by Th32 .= ((X \/ Y) /\ X) \/ ((X \/ Y) /\ Z) by Th30 .= (X \/ Y) /\ (X \/ Z) by Th32 ; ::_thesis: verum end; theorem :: PBOOLE:34 for I being set for X, Y, Z being ManySortedSet of I st (X /\ Y) \/ (X /\ Z) = X holds X c= Y \/ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st (X /\ Y) \/ (X /\ Z) = X holds X c= Y \/ Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( (X /\ Y) \/ (X /\ Z) = X implies X c= Y \/ Z ) assume (X /\ Y) \/ (X /\ Z) = X ; ::_thesis: X c= Y \/ Z then X = X /\ (Y \/ Z) by Th32; hence X c= Y \/ Z by Th15; ::_thesis: verum end; theorem :: PBOOLE:35 for I being set for X, Y, Z being ManySortedSet of I st (X \/ Y) /\ (X \/ Z) = X holds Y /\ Z c= X proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st (X \/ Y) /\ (X \/ Z) = X holds Y /\ Z c= X let X, Y, Z be ManySortedSet of I; ::_thesis: ( (X \/ Y) /\ (X \/ Z) = X implies Y /\ Z c= X ) assume (X \/ Y) /\ (X \/ Z) = X ; ::_thesis: Y /\ Z c= X then X = X \/ (Y /\ Z) by Th33; hence Y /\ Z c= X by Th14; ::_thesis: verum end; theorem :: PBOOLE:36 for I being set for X, Y, Z being ManySortedSet of I holds ((X /\ Y) \/ (Y /\ Z)) \/ (Z /\ X) = ((X \/ Y) /\ (Y \/ Z)) /\ (Z \/ X) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds ((X /\ Y) \/ (Y /\ Z)) \/ (Z /\ X) = ((X \/ Y) /\ (Y \/ Z)) /\ (Z \/ X) let X, Y, Z be ManySortedSet of I; ::_thesis: ((X /\ Y) \/ (Y /\ Z)) \/ (Z /\ X) = ((X \/ Y) /\ (Y \/ Z)) /\ (Z \/ X) thus ((X /\ Y) \/ (Y /\ Z)) \/ (Z /\ X) = (((X /\ Y) \/ (Y /\ Z)) \/ Z) /\ (((X /\ Y) \/ (Y /\ Z)) \/ X) by Th33 .= ((X /\ Y) \/ ((Y /\ Z) \/ Z)) /\ (((X /\ Y) \/ (Y /\ Z)) \/ X) by Th28 .= ((X /\ Y) \/ Z) /\ (((X /\ Y) \/ (Y /\ Z)) \/ X) by Th31 .= ((X /\ Y) \/ Z) /\ (((X /\ Y) \/ X) \/ (Y /\ Z)) by Th28 .= ((X /\ Y) \/ Z) /\ (X \/ (Y /\ Z)) by Th31 .= ((X \/ Z) /\ (Y \/ Z)) /\ (X \/ (Y /\ Z)) by Th33 .= ((X \/ Z) /\ (Y \/ Z)) /\ ((X \/ Y) /\ (X \/ Z)) by Th33 .= (X \/ Y) /\ (((Y \/ Z) /\ (X \/ Z)) /\ (X \/ Z)) by Th29 .= (X \/ Y) /\ ((Y \/ Z) /\ ((X \/ Z) /\ (X \/ Z))) by Th29 .= ((X \/ Y) /\ (Y \/ Z)) /\ (Z \/ X) by Th29 ; ::_thesis: verum end; theorem :: PBOOLE:37 for I being set for X, Y, Z being ManySortedSet of I st X \/ Y c= Z holds X c= Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X \/ Y c= Z holds X c= Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X \/ Y c= Z implies X c= Z ) X c= X \/ Y by Th14; hence ( X \/ Y c= Z implies X c= Z ) by Th13; ::_thesis: verum end; theorem :: PBOOLE:38 for I being set for X, Y, Z being ManySortedSet of I st X c= Y /\ Z holds X c= Y proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y /\ Z holds X c= Y let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y /\ Z implies X c= Y ) Y /\ Z c= Y by Th15; hence ( X c= Y /\ Z implies X c= Y ) by Th13; ::_thesis: verum end; theorem :: PBOOLE:39 for I being set for X, Y, Z being ManySortedSet of I holds (X \/ Y) \/ Z = (X \/ Z) \/ (Y \/ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X \/ Y) \/ Z = (X \/ Z) \/ (Y \/ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X \/ Y) \/ Z = (X \/ Z) \/ (Y \/ Z) thus (X \/ Y) \/ Z = X \/ (Y \/ (Z \/ Z)) by Th28 .= X \/ ((Z \/ Y) \/ Z) by Th28 .= (X \/ Z) \/ (Y \/ Z) by Th28 ; ::_thesis: verum end; theorem :: PBOOLE:40 for I being set for X, Y, Z being ManySortedSet of I holds (X /\ Y) /\ Z = (X /\ Z) /\ (Y /\ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X /\ Y) /\ Z = (X /\ Z) /\ (Y /\ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X /\ Y) /\ Z = (X /\ Z) /\ (Y /\ Z) thus (X /\ Y) /\ Z = X /\ (Y /\ (Z /\ Z)) by Th29 .= X /\ ((Z /\ Y) /\ Z) by Th29 .= (X /\ Z) /\ (Y /\ Z) by Th29 ; ::_thesis: verum end; theorem :: PBOOLE:41 for I being set for X, Y being ManySortedSet of I holds X \/ (X \/ Y) = X \/ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \/ (X \/ Y) = X \/ Y let X, Y be ManySortedSet of I; ::_thesis: X \/ (X \/ Y) = X \/ Y thus X \/ (X \/ Y) = (X \/ X) \/ Y by Th28 .= X \/ Y ; ::_thesis: verum end; theorem :: PBOOLE:42 for I being set for X, Y being ManySortedSet of I holds X /\ (X /\ Y) = X /\ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X /\ (X /\ Y) = X /\ Y let X, Y be ManySortedSet of I; ::_thesis: X /\ (X /\ Y) = X /\ Y thus X /\ (X /\ Y) = (X /\ X) /\ Y by Th29 .= X /\ Y ; ::_thesis: verum end; begin theorem Th43: :: PBOOLE:43 for I being set for X being ManySortedSet of I holds [[0]] I c= X proof let I be set ; ::_thesis: for X being ManySortedSet of I holds [[0]] I c= X let X be ManySortedSet of I; ::_thesis: [[0]] I c= X let i be set ; :: according to PBOOLE:def_2 ::_thesis: ( i in I implies ([[0]] I) . i c= X . i ) assume A1: i in I ; ::_thesis: ([[0]] I) . i c= X . i let e be set ; :: according to TARSKI:def_3 ::_thesis: ( not e in ([[0]] I) . i or e in X . i ) assume e in ([[0]] I) . i ; ::_thesis: e in X . i hence e in X . i by A1, FUNCOP_1:7; ::_thesis: verum end; theorem Th44: :: PBOOLE:44 for I being set for X being ManySortedSet of I st X c= [[0]] I holds X = [[0]] I proof let I be set ; ::_thesis: for X being ManySortedSet of I st X c= [[0]] I holds X = [[0]] I let X be ManySortedSet of I; ::_thesis: ( X c= [[0]] I implies X = [[0]] I ) assume X c= [[0]] I ; ::_thesis: X = [[0]] I then ( X c= [[0]] I & [[0]] I c= X ) by Th43; hence X = [[0]] I by Lm1; ::_thesis: verum end; theorem :: PBOOLE:45 for I being set for X, Y, Z being ManySortedSet of I st X c= Y & X c= Z & Y /\ Z = [[0]] I holds X = [[0]] I by Th17, Th44; theorem :: PBOOLE:46 for I being set for X, Y, Z being ManySortedSet of I st X c= Y & Y /\ Z = [[0]] I holds X /\ Z = [[0]] I by Th44, Th19; theorem :: PBOOLE:47 for I being set for X being ManySortedSet of I holds ( X \/ ([[0]] I) = X & ([[0]] I) \/ X = X ) by Th22, Th43; theorem :: PBOOLE:48 for I being set for X, Y being ManySortedSet of I st X \/ Y = [[0]] I holds X = [[0]] I by Th44, Th14; theorem :: PBOOLE:49 for I being set for X being ManySortedSet of I holds X /\ ([[0]] I) = [[0]] I by Th23, Th43; theorem :: PBOOLE:50 for I being set for X, Y, Z being ManySortedSet of I st X c= Y \/ Z & X /\ Z = [[0]] I holds X c= Y proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y \/ Z & X /\ Z = [[0]] I holds X c= Y let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y \/ Z & X /\ Z = [[0]] I implies X c= Y ) assume that A1: X c= Y \/ Z and A2: X /\ Z = [[0]] I ; ::_thesis: X c= Y X /\ (Y \/ Z) = X by A1, Th23; then (Y /\ X) \/ ([[0]] I) = X by A2, Th32; then Y /\ X = X by Th22, Th43; hence X c= Y by Th15; ::_thesis: verum end; theorem :: PBOOLE:51 for I being set for Y, X being ManySortedSet of I st Y c= X & X /\ Y = [[0]] I holds Y = [[0]] I by Th23; begin theorem Th52: :: PBOOLE:52 for I being set for X, Y being ManySortedSet of I holds ( X \ Y = [[0]] I iff X c= Y ) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds ( X \ Y = [[0]] I iff X c= Y ) let X, Y be ManySortedSet of I; ::_thesis: ( X \ Y = [[0]] I iff X c= Y ) hereby ::_thesis: ( X c= Y implies X \ Y = [[0]] I ) assume A1: X \ Y = [[0]] I ; ::_thesis: X c= Y now__::_thesis:_for_i_being_set_st_i_in_I_holds_ X_._i_c=_Y_._i let i be set ; ::_thesis: ( i in I implies X . i c= Y . i ) assume i in I ; ::_thesis: X . i c= Y . i then (X . i) \ (Y . i) = (X \ Y) . i by Def6 .= {} by A1, Th5 ; hence X . i c= Y . i by XBOOLE_1:37; ::_thesis: verum end; hence X c= Y by Def2; ::_thesis: verum end; assume A2: X c= Y ; ::_thesis: X \ Y = [[0]] I now__::_thesis:_for_i_being_set_st_i_in_I_holds_ (X_\_Y)_._i_=_{} let i be set ; ::_thesis: ( i in I implies (X \ Y) . i = {} ) assume A3: i in I ; ::_thesis: (X \ Y) . i = {} then A4: X . i c= Y . i by A2, Def2; thus (X \ Y) . i = (X . i) \ (Y . i) by A3, Def6 .= {} by A4, XBOOLE_1:37 ; ::_thesis: verum end; hence X \ Y = [[0]] I by Th6; ::_thesis: verum end; theorem Th53: :: PBOOLE:53 for I being set for X, Y, Z being ManySortedSet of I st X c= Y holds X \ Z c= Y \ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y holds X \ Z c= Y \ Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y implies X \ Z c= Y \ Z ) assume A1: X c= Y ; ::_thesis: X \ Z c= Y \ Z now__::_thesis:_for_i_being_set_st_i_in_I_holds_ (X_\_Z)_._i_c=_(Y_\_Z)_._i let i be set ; ::_thesis: ( i in I implies (X \ Z) . i c= (Y \ Z) . i ) assume A2: i in I ; ::_thesis: (X \ Z) . i c= (Y \ Z) . i then A3: ( (X \ Z) . i = (X . i) \ (Z . i) & (Y \ Z) . i = (Y . i) \ (Z . i) ) by Def6; X . i c= Y . i by A1, A2, Def2; hence (X \ Z) . i c= (Y \ Z) . i by A3, XBOOLE_1:33; ::_thesis: verum end; hence X \ Z c= Y \ Z by Def2; ::_thesis: verum end; theorem Th54: :: PBOOLE:54 for I being set for X, Y, Z being ManySortedSet of I st X c= Y holds Z \ Y c= Z \ X proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y holds Z \ Y c= Z \ X let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y implies Z \ Y c= Z \ X ) assume A1: X c= Y ; ::_thesis: Z \ Y c= Z \ X now__::_thesis:_for_i_being_set_st_i_in_I_holds_ (Z_\_Y)_._i_c=_(Z_\_X)_._i let i be set ; ::_thesis: ( i in I implies (Z \ Y) . i c= (Z \ X) . i ) assume A2: i in I ; ::_thesis: (Z \ Y) . i c= (Z \ X) . i then A3: ( (Z \ X) . i = (Z . i) \ (X . i) & (Z \ Y) . i = (Z . i) \ (Y . i) ) by Def6; X . i c= Y . i by A1, A2, Def2; hence (Z \ Y) . i c= (Z \ X) . i by A3, XBOOLE_1:34; ::_thesis: verum end; hence Z \ Y c= Z \ X by Def2; ::_thesis: verum end; theorem :: PBOOLE:55 for I being set for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V holds X \ V c= Y \ Z proof let I be set ; ::_thesis: for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V holds X \ V c= Y \ Z let X, Y, Z, V be ManySortedSet of I; ::_thesis: ( X c= Y & Z c= V implies X \ V c= Y \ Z ) assume ( X c= Y & Z c= V ) ; ::_thesis: X \ V c= Y \ Z then ( X \ V c= Y \ V & Y \ V c= Y \ Z ) by Th53, Th54; hence X \ V c= Y \ Z by Th13; ::_thesis: verum end; theorem Th56: :: PBOOLE:56 for I being set for X, Y being ManySortedSet of I holds X \ Y c= X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \ Y c= X let X, Y be ManySortedSet of I; ::_thesis: X \ Y c= X now__::_thesis:_for_i_being_set_st_i_in_I_holds_ (X_\_Y)_._i_c=_X_._i let i be set ; ::_thesis: ( i in I implies (X \ Y) . i c= X . i ) assume A1: i in I ; ::_thesis: (X \ Y) . i c= X . i (X . i) \ (Y . i) c= X . i ; hence (X \ Y) . i c= X . i by A1, Def6; ::_thesis: verum end; hence X \ Y c= X by Def2; ::_thesis: verum end; theorem :: PBOOLE:57 for I being set for X, Y being ManySortedSet of I st X c= Y \ X holds X = [[0]] I proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X c= Y \ X holds X = [[0]] I let X, Y be ManySortedSet of I; ::_thesis: ( X c= Y \ X implies X = [[0]] I ) assume A1: X c= Y \ X ; ::_thesis: X = [[0]] I let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies X . i = ([[0]] I) . i ) assume A2: i in I ; ::_thesis: X . i = ([[0]] I) . i then X . i c= (Y \ X) . i by A1, Def2; then X . i c= (Y . i) \ (X . i) by A2, Def6; hence X . i = {} by XBOOLE_1:38 .= ([[0]] I) . i by Th5 ; ::_thesis: verum end; theorem :: PBOOLE:58 for I being set for X being ManySortedSet of I holds X \ X = [[0]] I by Th52; theorem Th59: :: PBOOLE:59 for I being set for X being ManySortedSet of I holds X \ ([[0]] I) = X proof let I be set ; ::_thesis: for X being ManySortedSet of I holds X \ ([[0]] I) = X let X be ManySortedSet of I; ::_thesis: X \ ([[0]] I) = X let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies (X \ ([[0]] I)) . i = X . i ) assume i in I ; ::_thesis: (X \ ([[0]] I)) . i = X . i hence (X \ ([[0]] I)) . i = (X . i) \ (([[0]] I) . i) by Def6 .= (X . i) \ {} by Th5 .= X . i ; ::_thesis: verum end; theorem Th60: :: PBOOLE:60 for I being set for X being ManySortedSet of I holds ([[0]] I) \ X = [[0]] I proof let I be set ; ::_thesis: for X being ManySortedSet of I holds ([[0]] I) \ X = [[0]] I let X be ManySortedSet of I; ::_thesis: ([[0]] I) \ X = [[0]] I [[0]] I c= X by Th43; hence ([[0]] I) \ X = [[0]] I by Th52; ::_thesis: verum end; theorem :: PBOOLE:61 for I being set for X, Y being ManySortedSet of I holds X \ (X \/ Y) = [[0]] I proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \ (X \/ Y) = [[0]] I let X, Y be ManySortedSet of I; ::_thesis: X \ (X \/ Y) = [[0]] I X c= X \/ Y by Th14; hence X \ (X \/ Y) = [[0]] I by Th52; ::_thesis: verum end; theorem Th62: :: PBOOLE:62 for I being set for X, Y, Z being ManySortedSet of I holds X /\ (Y \ Z) = (X /\ Y) \ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X /\ (Y \ Z) = (X /\ Y) \ Z let X, Y, Z be ManySortedSet of I; ::_thesis: X /\ (Y \ Z) = (X /\ Y) \ Z let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies (X /\ (Y \ Z)) . i = ((X /\ Y) \ Z) . i ) assume A1: i in I ; ::_thesis: (X /\ (Y \ Z)) . i = ((X /\ Y) \ Z) . i hence (X /\ (Y \ Z)) . i = (X . i) /\ ((Y \ Z) . i) by Def5 .= (X . i) /\ ((Y . i) \ (Z . i)) by A1, Def6 .= ((X . i) /\ (Y . i)) \ (Z . i) by XBOOLE_1:49 .= ((X /\ Y) . i) \ (Z . i) by A1, Def5 .= ((X /\ Y) \ Z) . i by A1, Def6 ; ::_thesis: verum end; theorem Th63: :: PBOOLE:63 for I being set for X, Y being ManySortedSet of I holds (X \ Y) /\ Y = [[0]] I proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds (X \ Y) /\ Y = [[0]] I let X, Y be ManySortedSet of I; ::_thesis: (X \ Y) /\ Y = [[0]] I A1: Y /\ X c= Y by Th15; thus (X \ Y) /\ Y = (Y /\ X) \ Y by Th62 .= [[0]] I by A1, Th52 ; ::_thesis: verum thus verum ; ::_thesis: verum end; theorem Th64: :: PBOOLE:64 for I being set for X, Y, Z being ManySortedSet of I holds X \ (Y \ Z) = (X \ Y) \/ (X /\ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X \ (Y \ Z) = (X \ Y) \/ (X /\ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: X \ (Y \ Z) = (X \ Y) \/ (X /\ Z) let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies (X \ (Y \ Z)) . i = ((X \ Y) \/ (X /\ Z)) . i ) assume A1: i in I ; ::_thesis: (X \ (Y \ Z)) . i = ((X \ Y) \/ (X /\ Z)) . i hence (X \ (Y \ Z)) . i = (X . i) \ ((Y \ Z) . i) by Def6 .= (X . i) \ ((Y . i) \ (Z . i)) by A1, Def6 .= ((X . i) \ (Y . i)) \/ ((X . i) /\ (Z . i)) by XBOOLE_1:52 .= ((X . i) \ (Y . i)) \/ ((X /\ Z) . i) by A1, Def5 .= ((X \ Y) . i) \/ ((X /\ Z) . i) by A1, Def6 .= ((X \ Y) \/ (X /\ Z)) . i by A1, Def4 ; ::_thesis: verum end; theorem Th65: :: PBOOLE:65 for I being set for X, Y being ManySortedSet of I holds (X \ Y) \/ (X /\ Y) = X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds (X \ Y) \/ (X /\ Y) = X let X, Y be ManySortedSet of I; ::_thesis: (X \ Y) \/ (X /\ Y) = X thus (X \ Y) \/ (X /\ Y) = X \ (Y \ Y) by Th64 .= X \ ([[0]] I) by Th52 .= X by Th59 ; ::_thesis: verum end; theorem :: PBOOLE:66 for I being set for X, Y being ManySortedSet of I st X c= Y holds Y = X \/ (Y \ X) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X c= Y holds Y = X \/ (Y \ X) let X, Y be ManySortedSet of I; ::_thesis: ( X c= Y implies Y = X \/ (Y \ X) ) assume A1: X c= Y ; ::_thesis: Y = X \/ (Y \ X) thus Y = (Y \ X) \/ (Y /\ X) by Th65 .= X \/ (Y \ X) by A1, Th23 ; ::_thesis: verum end; theorem Th67: :: PBOOLE:67 for I being set for X, Y being ManySortedSet of I holds X \/ (Y \ X) = X \/ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \/ (Y \ X) = X \/ Y let X, Y be ManySortedSet of I; ::_thesis: X \/ (Y \ X) = X \/ Y thus X \/ (Y \ X) = (X \/ (Y /\ X)) \/ (Y \ X) by Th31 .= X \/ ((Y /\ X) \/ (Y \ X)) by Th28 .= X \/ Y by Th65 ; ::_thesis: verum end; theorem Th68: :: PBOOLE:68 for I being set for X, Y being ManySortedSet of I holds X \ (X \ Y) = X /\ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \ (X \ Y) = X /\ Y let X, Y be ManySortedSet of I; ::_thesis: X \ (X \ Y) = X /\ Y thus X \ (X \ Y) = (X \ X) \/ (X /\ Y) by Th64 .= ([[0]] I) \/ (X /\ Y) by Th52 .= X /\ Y by Th22, Th43 ; ::_thesis: verum end; theorem Th69: :: PBOOLE:69 for I being set for X, Y, Z being ManySortedSet of I holds X \ (Y /\ Z) = (X \ Y) \/ (X \ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X \ (Y /\ Z) = (X \ Y) \/ (X \ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: X \ (Y /\ Z) = (X \ Y) \/ (X \ Z) let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies (X \ (Y /\ Z)) . i = ((X \ Y) \/ (X \ Z)) . i ) assume A1: i in I ; ::_thesis: (X \ (Y /\ Z)) . i = ((X \ Y) \/ (X \ Z)) . i hence (X \ (Y /\ Z)) . i = (X . i) \ ((Y /\ Z) . i) by Def6 .= (X . i) \ ((Y . i) /\ (Z . i)) by A1, Def5 .= ((X . i) \ (Y . i)) \/ ((X . i) \ (Z . i)) by XBOOLE_1:54 .= ((X . i) \ (Y . i)) \/ ((X \ Z) . i) by A1, Def6 .= ((X \ Y) . i) \/ ((X \ Z) . i) by A1, Def6 .= ((X \ Y) \/ (X \ Z)) . i by A1, Def4 ; ::_thesis: verum end; theorem Th70: :: PBOOLE:70 for I being set for X, Y being ManySortedSet of I holds X \ (X /\ Y) = X \ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \ (X /\ Y) = X \ Y let X, Y be ManySortedSet of I; ::_thesis: X \ (X /\ Y) = X \ Y thus X \ (X /\ Y) = (X \ X) \/ (X \ Y) by Th69 .= ([[0]] I) \/ (X \ Y) by Th52 .= X \ Y by Th22, Th43 ; ::_thesis: verum end; theorem :: PBOOLE:71 for I being set for X, Y being ManySortedSet of I holds ( X /\ Y = [[0]] I iff X \ Y = X ) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds ( X /\ Y = [[0]] I iff X \ Y = X ) let X, Y be ManySortedSet of I; ::_thesis: ( X /\ Y = [[0]] I iff X \ Y = X ) hereby ::_thesis: ( X \ Y = X implies X /\ Y = [[0]] I ) assume A1: X /\ Y = [[0]] I ; ::_thesis: X \ Y = X thus X \ Y = X \ (X /\ Y) by Th70 .= X by A1, Th59 ; ::_thesis: verum end; thus ( X \ Y = X implies X /\ Y = [[0]] I ) by Th63; ::_thesis: verum end; theorem Th72: :: PBOOLE:72 for I being set for X, Y, Z being ManySortedSet of I holds (X \/ Y) \ Z = (X \ Z) \/ (Y \ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X \/ Y) \ Z = (X \ Z) \/ (Y \ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X \/ Y) \ Z = (X \ Z) \/ (Y \ Z) let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies ((X \/ Y) \ Z) . i = ((X \ Z) \/ (Y \ Z)) . i ) assume A1: i in I ; ::_thesis: ((X \/ Y) \ Z) . i = ((X \ Z) \/ (Y \ Z)) . i hence ((X \/ Y) \ Z) . i = ((X \/ Y) . i) \ (Z . i) by Def6 .= ((X . i) \/ (Y . i)) \ (Z . i) by A1, Def4 .= ((X . i) \ (Z . i)) \/ ((Y . i) \ (Z . i)) by XBOOLE_1:42 .= ((X . i) \ (Z . i)) \/ ((Y \ Z) . i) by A1, Def6 .= ((X \ Z) . i) \/ ((Y \ Z) . i) by A1, Def6 .= ((X \ Z) \/ (Y \ Z)) . i by A1, Def4 ; ::_thesis: verum end; theorem Th73: :: PBOOLE:73 for I being set for X, Y, Z being ManySortedSet of I holds (X \ Y) \ Z = X \ (Y \/ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X \ Y) \ Z = X \ (Y \/ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X \ Y) \ Z = X \ (Y \/ Z) let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies ((X \ Y) \ Z) . i = (X \ (Y \/ Z)) . i ) assume A1: i in I ; ::_thesis: ((X \ Y) \ Z) . i = (X \ (Y \/ Z)) . i hence ((X \ Y) \ Z) . i = ((X \ Y) . i) \ (Z . i) by Def6 .= ((X . i) \ (Y . i)) \ (Z . i) by A1, Def6 .= (X . i) \ ((Y . i) \/ (Z . i)) by XBOOLE_1:41 .= (X . i) \ ((Y \/ Z) . i) by A1, Def4 .= (X \ (Y \/ Z)) . i by A1, Def6 ; ::_thesis: verum end; theorem :: PBOOLE:74 for I being set for X, Y, Z being ManySortedSet of I holds (X /\ Y) \ Z = (X \ Z) /\ (Y \ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X /\ Y) \ Z = (X \ Z) /\ (Y \ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X /\ Y) \ Z = (X \ Z) /\ (Y \ Z) A1: X \ Z c= X by Th56; thus (X /\ Y) \ Z = (X \ Z) /\ Y by Th62 .= (X \ Z) \ ((X \ Z) \ Y) by Th68 .= (X \ Z) \ (X \ (Z \/ Y)) by Th73 .= ((X \ Z) \ X) \/ ((X \ Z) /\ (Z \/ Y)) by Th64 .= ([[0]] I) \/ ((X \ Z) /\ (Z \/ Y)) by A1, Th52 .= (X \ Z) /\ (Y \/ Z) by Th22, Th43 .= (X \ Z) /\ ((Y \ Z) \/ Z) by Th67 .= ((X \ Z) /\ (Y \ Z)) \/ ((X \ Z) /\ Z) by Th32 .= ((X \ Z) /\ (Y \ Z)) \/ ([[0]] I) by Th63 .= (X \ Z) /\ (Y \ Z) by Th22, Th43 ; ::_thesis: verum end; theorem Th75: :: PBOOLE:75 for I being set for X, Y being ManySortedSet of I holds (X \/ Y) \ Y = X \ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds (X \/ Y) \ Y = X \ Y let X, Y be ManySortedSet of I; ::_thesis: (X \/ Y) \ Y = X \ Y thus (X \/ Y) \ Y = (X \ Y) \/ (Y \ Y) by Th72 .= (X \ Y) \/ ([[0]] I) by Th52 .= X \ Y by Th22, Th43 ; ::_thesis: verum end; theorem :: PBOOLE:76 for I being set for X, Y, Z being ManySortedSet of I st X c= Y \/ Z holds ( X \ Y c= Z & X \ Z c= Y ) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y \/ Z holds ( X \ Y c= Z & X \ Z c= Y ) let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y \/ Z implies ( X \ Y c= Z & X \ Z c= Y ) ) assume A1: X c= Y \/ Z ; ::_thesis: ( X \ Y c= Z & X \ Z c= Y ) then X \ Y c= (Z \/ Y) \ Y by Th53; then A2: X \ Y c= Z \ Y by Th75; Z \ Y c= Z by Th56; hence X \ Y c= Z by A2, Th13; ::_thesis: X \ Z c= Y X \ Z c= (Y \/ Z) \ Z by A1, Th53; then A3: X \ Z c= Y \ Z by Th75; Y \ Z c= Y by Th56; hence X \ Z c= Y by A3, Th13; ::_thesis: verum end; theorem Th77: :: PBOOLE:77 for I being set for X, Y being ManySortedSet of I holds (X \/ Y) \ (X /\ Y) = (X \ Y) \/ (Y \ X) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds (X \/ Y) \ (X /\ Y) = (X \ Y) \/ (Y \ X) let X, Y be ManySortedSet of I; ::_thesis: (X \/ Y) \ (X /\ Y) = (X \ Y) \/ (Y \ X) thus (X \/ Y) \ (X /\ Y) = (X \ (X /\ Y)) \/ (Y \ (X /\ Y)) by Th72 .= (X \ Y) \/ (Y \ (X /\ Y)) by Th70 .= (X \ Y) \/ (Y \ X) by Th70 ; ::_thesis: verum end; theorem Th78: :: PBOOLE:78 for I being set for X, Y being ManySortedSet of I holds (X \ Y) \ Y = X \ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds (X \ Y) \ Y = X \ Y let X, Y be ManySortedSet of I; ::_thesis: (X \ Y) \ Y = X \ Y thus (X \ Y) \ Y = X \ (Y \/ Y) by Th73 .= X \ Y ; ::_thesis: verum end; theorem :: PBOOLE:79 for I being set for X, Y, Z being ManySortedSet of I holds X \ (Y \/ Z) = (X \ Y) /\ (X \ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X \ (Y \/ Z) = (X \ Y) /\ (X \ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: X \ (Y \/ Z) = (X \ Y) /\ (X \ Z) thus X \ (Y \/ Z) = (X \ Y) \ Z by Th73 .= ((X \ Y) /\ X) \ Z by Th56, Th23 .= (X \ Y) /\ (X \ Z) by Th62 ; ::_thesis: verum end; theorem :: PBOOLE:80 for I being set for X, Y being ManySortedSet of I st X \ Y = Y \ X holds X = Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X \ Y = Y \ X holds X = Y let X, Y be ManySortedSet of I; ::_thesis: ( X \ Y = Y \ X implies X = Y ) assume X \ Y = Y \ X ; ::_thesis: X = Y hence X = (Y \ X) \/ (Y /\ X) by Th65 .= Y by Th65 ; ::_thesis: verum end; theorem :: PBOOLE:81 for I being set for X, Y, Z being ManySortedSet of I holds X /\ (Y \ Z) = (X /\ Y) \ (X /\ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X /\ (Y \ Z) = (X /\ Y) \ (X /\ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: X /\ (Y \ Z) = (X /\ Y) \ (X /\ Z) A1: X /\ Y c= X by Th15; (X /\ Y) \ (X /\ Z) = ((X /\ Y) \ X) \/ ((X /\ Y) \ Z) by Th69 .= ([[0]] I) \/ ((X /\ Y) \ Z) by A1, Th52 .= (X /\ Y) \ Z by Th22, Th43 ; hence X /\ (Y \ Z) = (X /\ Y) \ (X /\ Z) by Th62; ::_thesis: verum end; theorem :: PBOOLE:82 for I being set for X, Y, Z being ManySortedSet of I st X \ Y c= Z holds X c= Y \/ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X \ Y c= Z holds X c= Y \/ Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X \ Y c= Z implies X c= Y \/ Z ) assume A1: X \ Y c= Z ; ::_thesis: X c= Y \/ Z X /\ Y c= Y by Th15; then (X /\ Y) \/ (X \ Y) c= Y \/ Z by A1, Th20; hence X c= Y \/ Z by Th65; ::_thesis: verum end; theorem :: PBOOLE:83 for I being set for X, Y being ManySortedSet of I holds X \ Y c= X \+\ Y by Th14; theorem :: PBOOLE:84 for I being set for X being ManySortedSet of I holds X \+\ ([[0]] I) = X proof let I be set ; ::_thesis: for X being ManySortedSet of I holds X \+\ ([[0]] I) = X let X be ManySortedSet of I; ::_thesis: X \+\ ([[0]] I) = X thus X \+\ ([[0]] I) = X \/ (([[0]] I) \ X) by Th59 .= X \/ ([[0]] I) by Th60 .= X by Th22, Th43 ; ::_thesis: verum end; theorem :: PBOOLE:85 for I being set for X being ManySortedSet of I holds X \+\ X = [[0]] I by Th52; theorem :: PBOOLE:86 for I being set for X, Y being ManySortedSet of I holds X \/ Y = (X \+\ Y) \/ (X /\ Y) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \/ Y = (X \+\ Y) \/ (X /\ Y) let X, Y be ManySortedSet of I; ::_thesis: X \/ Y = (X \+\ Y) \/ (X /\ Y) thus X \/ Y = ((X \ Y) \/ (X /\ Y)) \/ Y by Th65 .= (X \ Y) \/ ((X /\ Y) \/ Y) by Th28 .= (X \ Y) \/ Y by Th31 .= (X \ Y) \/ ((Y \ X) \/ (Y /\ X)) by Th65 .= (X \+\ Y) \/ (X /\ Y) by Th28 ; ::_thesis: verum end; theorem Th87: :: PBOOLE:87 for I being set for X, Y being ManySortedSet of I holds X \+\ Y = (X \/ Y) \ (X /\ Y) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \+\ Y = (X \/ Y) \ (X /\ Y) let X, Y be ManySortedSet of I; ::_thesis: X \+\ Y = (X \/ Y) \ (X /\ Y) thus X \+\ Y = (X \ (X /\ Y)) \/ (Y \ X) by Th70 .= (X \ (X /\ Y)) \/ (Y \ (X /\ Y)) by Th70 .= (X \/ Y) \ (X /\ Y) by Th72 ; ::_thesis: verum end; theorem :: PBOOLE:88 for I being set for X, Y, Z being ManySortedSet of I holds (X \+\ Y) \ Z = (X \ (Y \/ Z)) \/ (Y \ (X \/ Z)) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X \+\ Y) \ Z = (X \ (Y \/ Z)) \/ (Y \ (X \/ Z)) let X, Y, Z be ManySortedSet of I; ::_thesis: (X \+\ Y) \ Z = (X \ (Y \/ Z)) \/ (Y \ (X \/ Z)) thus (X \+\ Y) \ Z = ((X \ Y) \ Z) \/ ((Y \ X) \ Z) by Th72 .= (X \ (Y \/ Z)) \/ ((Y \ X) \ Z) by Th73 .= (X \ (Y \/ Z)) \/ (Y \ (X \/ Z)) by Th73 ; ::_thesis: verum end; theorem :: PBOOLE:89 for I being set for X, Y, Z being ManySortedSet of I holds X \ (Y \+\ Z) = (X \ (Y \/ Z)) \/ ((X /\ Y) /\ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds X \ (Y \+\ Z) = (X \ (Y \/ Z)) \/ ((X /\ Y) /\ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: X \ (Y \+\ Z) = (X \ (Y \/ Z)) \/ ((X /\ Y) /\ Z) thus X \ (Y \+\ Z) = X \ ((Y \/ Z) \ (Y /\ Z)) by Th87 .= (X \ (Y \/ Z)) \/ (X /\ (Y /\ Z)) by Th64 .= (X \ (Y \/ Z)) \/ ((X /\ Y) /\ Z) by Th29 ; ::_thesis: verum end; theorem Th90: :: PBOOLE:90 for I being set for X, Y, Z being ManySortedSet of I holds (X \+\ Y) \+\ Z = X \+\ (Y \+\ Z) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I holds (X \+\ Y) \+\ Z = X \+\ (Y \+\ Z) let X, Y, Z be ManySortedSet of I; ::_thesis: (X \+\ Y) \+\ Z = X \+\ (Y \+\ Z) set S1 = X \ (Y \/ Z); set S2 = Y \ (X \/ Z); set S3 = Z \ (X \/ Y); set S4 = (X /\ Y) /\ Z; thus (X \+\ Y) \+\ Z = (((X \ Y) \ Z) \/ ((Y \ X) \ Z)) \/ (Z \ ((X \ Y) \/ (Y \ X))) by Th72 .= ((X \ (Y \/ Z)) \/ ((Y \ X) \ Z)) \/ (Z \ ((X \ Y) \/ (Y \ X))) by Th73 .= ((X \ (Y \/ Z)) \/ (Y \ (X \/ Z))) \/ (Z \ ((X \ Y) \/ (Y \ X))) by Th73 .= ((X \ (Y \/ Z)) \/ (Y \ (X \/ Z))) \/ (Z \ ((X \/ Y) \ (X /\ Y))) by Th77 .= ((X \ (Y \/ Z)) \/ (Y \ (X \/ Z))) \/ (((X /\ Y) /\ Z) \/ (Z \ (X \/ Y))) by Th64 .= (((X \ (Y \/ Z)) \/ (Y \ (X \/ Z))) \/ ((X /\ Y) /\ Z)) \/ (Z \ (X \/ Y)) by Th28 .= (((X \ (Y \/ Z)) \/ ((X /\ Y) /\ Z)) \/ (Y \ (X \/ Z))) \/ (Z \ (X \/ Y)) by Th28 .= ((X \ (Y \/ Z)) \/ ((X /\ Y) /\ Z)) \/ ((Y \ (X \/ Z)) \/ (Z \ (X \/ Y))) by Th28 .= ((X \ (Y \/ Z)) \/ (X /\ (Y /\ Z))) \/ ((Y \ (X \/ Z)) \/ (Z \ (X \/ Y))) by Th29 .= (X \ ((Y \/ Z) \ (Y /\ Z))) \/ ((Y \ (X \/ Z)) \/ (Z \ (X \/ Y))) by Th64 .= (X \ ((Y \ Z) \/ (Z \ Y))) \/ ((Y \ (X \/ Z)) \/ (Z \ (Y \/ X))) by Th77 .= (X \ ((Y \ Z) \/ (Z \ Y))) \/ ((Y \ (Z \/ X)) \/ ((Z \ Y) \ X)) by Th73 .= (X \ ((Y \ Z) \/ (Z \ Y))) \/ (((Y \ Z) \ X) \/ ((Z \ Y) \ X)) by Th73 .= X \+\ (Y \+\ Z) by Th72 ; ::_thesis: verum end; theorem :: PBOOLE:91 for I being set for X, Y, Z being ManySortedSet of I st X \ Y c= Z & Y \ X c= Z holds X \+\ Y c= Z by Th16; theorem Th92: :: PBOOLE:92 for I being set for X, Y being ManySortedSet of I holds X \/ Y = X \+\ (Y \ X) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \/ Y = X \+\ (Y \ X) let X, Y be ManySortedSet of I; ::_thesis: X \/ Y = X \+\ (Y \ X) thus X \/ Y = Y \/ (X \/ X) .= (X \/ Y) \/ X by Th28 .= ((X \ Y) \/ Y) \/ X by Th67 .= (X \ Y) \/ (X \/ Y) by Th28 .= (X \ Y) \/ (X \/ (Y \ X)) by Th67 .= ((X \ Y) \/ (X /\ X)) \/ (Y \ X) by Th28 .= (X \ (Y \ X)) \/ (Y \ X) by Th64 .= X \+\ (Y \ X) by Th78 ; ::_thesis: verum end; theorem Th93: :: PBOOLE:93 for I being set for X, Y being ManySortedSet of I holds X /\ Y = X \+\ (X \ Y) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X /\ Y = X \+\ (X \ Y) let X, Y be ManySortedSet of I; ::_thesis: X /\ Y = X \+\ (X \ Y) A1: X \ Y c= X by Th56; thus X /\ Y = X \ (X \ Y) by Th68 .= (X \ (X \ Y)) \/ ([[0]] I) by Th22, Th43 .= X \+\ (X \ Y) by A1, Th52 ; ::_thesis: verum end; theorem Th94: :: PBOOLE:94 for I being set for X, Y being ManySortedSet of I holds X \ Y = X \+\ (X /\ Y) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \ Y = X \+\ (X /\ Y) let X, Y be ManySortedSet of I; ::_thesis: X \ Y = X \+\ (X /\ Y) A1: X /\ Y c= X by Th15; thus X \ Y = X \ (X /\ Y) by Th70 .= (X \ (X /\ Y)) \/ ([[0]] I) by Th22, Th43 .= X \+\ (X /\ Y) by A1, Th52 ; ::_thesis: verum end; theorem Th95: :: PBOOLE:95 for I being set for Y, X being ManySortedSet of I holds Y \ X = X \+\ (X \/ Y) proof let I be set ; ::_thesis: for Y, X being ManySortedSet of I holds Y \ X = X \+\ (X \/ Y) let Y, X be ManySortedSet of I; ::_thesis: Y \ X = X \+\ (X \/ Y) A1: X c= Y \/ X by Th14; thus Y \ X = (Y \/ X) \ X by Th75 .= ([[0]] I) \/ ((Y \/ X) \ X) by Th22, Th43 .= X \+\ (X \/ Y) by A1, Th52 ; ::_thesis: verum end; theorem :: PBOOLE:96 for I being set for X, Y being ManySortedSet of I holds X \/ Y = (X \+\ Y) \+\ (X /\ Y) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \/ Y = (X \+\ Y) \+\ (X /\ Y) let X, Y be ManySortedSet of I; ::_thesis: X \/ Y = (X \+\ Y) \+\ (X /\ Y) thus X \/ Y = X \+\ (Y \ X) by Th92 .= X \+\ (Y \+\ (X /\ Y)) by Th94 .= (X \+\ Y) \+\ (X /\ Y) by Th90 ; ::_thesis: verum end; theorem :: PBOOLE:97 for I being set for X, Y being ManySortedSet of I holds X /\ Y = (X \+\ Y) \+\ (X \/ Y) proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X /\ Y = (X \+\ Y) \+\ (X \/ Y) let X, Y be ManySortedSet of I; ::_thesis: X /\ Y = (X \+\ Y) \+\ (X \/ Y) thus X /\ Y = X \+\ (X \ Y) by Th93 .= X \+\ (Y \+\ (X \/ Y)) by Th95 .= (X \+\ Y) \+\ (X \/ Y) by Th90 ; ::_thesis: verum end; begin theorem :: PBOOLE:98 for I being set for X, Y, Z being ManySortedSet of I st ( X overlaps Y or X overlaps Z ) holds X overlaps Y \/ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st ( X overlaps Y or X overlaps Z ) holds X overlaps Y \/ Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( ( X overlaps Y or X overlaps Z ) implies X overlaps Y \/ Z ) assume A1: ( X overlaps Y or X overlaps Z ) ; ::_thesis: X overlaps Y \/ Z percases ( X overlaps Y or X overlaps Z ) by A1; suppose X overlaps Y ; ::_thesis: X overlaps Y \/ Z then consider x being ManySortedSet of I such that A2: x in X and A3: x in Y by Th11; x in Y \/ Z by A3, Th7; hence X overlaps Y \/ Z by A2, Th10; ::_thesis: verum end; suppose X overlaps Z ; ::_thesis: X overlaps Y \/ Z then consider x being ManySortedSet of I such that A4: x in X and A5: x in Z by Th11; x in Y \/ Z by A5, Th7; hence X overlaps Y \/ Z by A4, Th10; ::_thesis: verum end; end; end; theorem Th99: :: PBOOLE:99 for I being set for X, Y, Z being ManySortedSet of I st X overlaps Y & Y c= Z holds X overlaps Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X overlaps Y & Y c= Z holds X overlaps Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X overlaps Y & Y c= Z implies X overlaps Z ) assume that A1: X overlaps Y and A2: Y c= Z ; ::_thesis: X overlaps Z consider x being ManySortedSet of I such that A3: x in X and A4: x in Y by A1, Th11; x in Z by A2, A4, Th9; hence X overlaps Z by A3, Th10; ::_thesis: verum end; theorem Th100: :: PBOOLE:100 for I being set for X, Y, Z being ManySortedSet of I st X overlaps Y & X c= Z holds Z overlaps Y proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X overlaps Y & X c= Z holds Z overlaps Y let X, Y, Z be ManySortedSet of I; ::_thesis: ( X overlaps Y & X c= Z implies Z overlaps Y ) assume that A1: X overlaps Y and A2: X c= Z ; ::_thesis: Z overlaps Y consider x being ManySortedSet of I such that A3: x in X and A4: x in Y by A1, Th11; x in Z by A2, A3, Th9; hence Z overlaps Y by A4, Th10; ::_thesis: verum end; theorem Th101: :: PBOOLE:101 for I being set for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V & X overlaps Z holds Y overlaps V proof let I be set ; ::_thesis: for X, Y, Z, V being ManySortedSet of I st X c= Y & Z c= V & X overlaps Z holds Y overlaps V let X, Y, Z, V be ManySortedSet of I; ::_thesis: ( X c= Y & Z c= V & X overlaps Z implies Y overlaps V ) assume that A1: X c= Y and A2: Z c= V ; ::_thesis: ( not X overlaps Z or Y overlaps V ) assume X overlaps Z ; ::_thesis: Y overlaps V then Y overlaps Z by A1, Th100; hence Y overlaps V by A2, Th99; ::_thesis: verum end; theorem :: PBOOLE:102 for I being set for X, Y, Z being ManySortedSet of I st X overlaps Y /\ Z holds ( X overlaps Y & X overlaps Z ) proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X overlaps Y /\ Z holds ( X overlaps Y & X overlaps Z ) let X, Y, Z be ManySortedSet of I; ::_thesis: ( X overlaps Y /\ Z implies ( X overlaps Y & X overlaps Z ) ) assume X overlaps Y /\ Z ; ::_thesis: ( X overlaps Y & X overlaps Z ) then consider x being ManySortedSet of I such that A1: x in X and A2: x in Y /\ Z by Th11; ( x in Y & x in Z ) by A2, Th8; hence ( X overlaps Y & X overlaps Z ) by A1, Th10; ::_thesis: verum end; theorem :: PBOOLE:103 for I being set for X, Z, V being ManySortedSet of I st X overlaps Z & X c= V holds X overlaps Z /\ V proof let I be set ; ::_thesis: for X, Z, V being ManySortedSet of I st X overlaps Z & X c= V holds X overlaps Z /\ V let X, Z, V be ManySortedSet of I; ::_thesis: ( X overlaps Z & X c= V implies X overlaps Z /\ V ) assume that A1: X overlaps Z and A2: X c= V ; ::_thesis: X overlaps Z /\ V consider x being ManySortedSet of I such that A3: x in X and A4: x in Z by A1, Th11; x in V by A2, A3, Th9; then x in Z /\ V by A4, Th8; hence X overlaps Z /\ V by A3, Th10; ::_thesis: verum end; theorem :: PBOOLE:104 for I being set for X, Y, Z being ManySortedSet of I st X overlaps Y \ Z holds X overlaps Y by Th56, Th99; theorem :: PBOOLE:105 for I being set for Y, Z, X being ManySortedSet of I st not Y overlaps Z holds not X /\ Y overlaps X /\ Z proof let I be set ; ::_thesis: for Y, Z, X being ManySortedSet of I st not Y overlaps Z holds not X /\ Y overlaps X /\ Z let Y, Z, X be ManySortedSet of I; ::_thesis: ( not Y overlaps Z implies not X /\ Y overlaps X /\ Z ) assume A1: not Y overlaps Z ; ::_thesis: not X /\ Y overlaps X /\ Z ( X /\ Y c= Y & X /\ Z c= Z ) by Th15; hence not X /\ Y overlaps X /\ Z by A1, Th101; ::_thesis: verum end; theorem :: PBOOLE:106 for I being set for X, Y, Z being ManySortedSet of I st X overlaps Y \ Z holds Y overlaps X \ Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X overlaps Y \ Z holds Y overlaps X \ Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X overlaps Y \ Z implies Y overlaps X \ Z ) assume A1: X overlaps Y \ Z ; ::_thesis: Y overlaps X \ Z let i be set ; :: according to PBOOLE:def_7 ::_thesis: ( i in I implies Y . i meets (X \ Z) . i ) assume A2: i in I ; ::_thesis: Y . i meets (X \ Z) . i then X . i meets (Y \ Z) . i by A1, Def7; then X . i meets (Y . i) \ (Z . i) by A2, Def6; then Y . i meets (X . i) \ (Z . i) by XBOOLE_1:81; hence Y . i meets (X \ Z) . i by A2, Def6; ::_thesis: verum end; theorem Th107: :: PBOOLE:107 for I being set for X, Y, Z being ManySortedSet of I st X meets Y & Y c= Z holds X meets Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X meets Y & Y c= Z holds X meets Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X meets Y & Y c= Z implies X meets Z ) assume that A1: X meets Y and A2: Y c= Z ; ::_thesis: X meets Z consider i being set such that A3: i in I and A4: X . i meets Y . i by A1, Def8; take i ; :: according to PBOOLE:def_8 ::_thesis: ( i in I & not X . i misses Z . i ) Y . i c= Z . i by A2, A3, Def2; hence ( i in I & not X . i misses Z . i ) by A3, A4, XBOOLE_1:63; ::_thesis: verum end; theorem Th108: :: PBOOLE:108 for I being set for Y, X being ManySortedSet of I holds Y misses X \ Y proof let I be set ; ::_thesis: for Y, X being ManySortedSet of I holds Y misses X \ Y let Y, X be ManySortedSet of I; ::_thesis: Y misses X \ Y now__::_thesis:_for_i_being_set_st_i_in_I_holds_ Y_._i_misses_(X_\_Y)_._i let i be set ; ::_thesis: ( i in I implies Y . i misses (X \ Y) . i ) assume i in I ; ::_thesis: Y . i misses (X \ Y) . i then (X \ Y) . i = (X . i) \ (Y . i) by Def6; hence Y . i misses (X \ Y) . i by XBOOLE_1:79; ::_thesis: verum end; hence Y misses X \ Y by Def8; ::_thesis: verum end; theorem :: PBOOLE:109 for I being set for X, Y being ManySortedSet of I holds X /\ Y misses X \ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X /\ Y misses X \ Y let X, Y be ManySortedSet of I; ::_thesis: X /\ Y misses X \ Y ( X /\ Y c= Y & X \ Y misses Y ) by Th15, Th108; hence X /\ Y misses X \ Y by Th107; ::_thesis: verum end; theorem :: PBOOLE:110 for I being set for X, Y being ManySortedSet of I holds X /\ Y misses X \+\ Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X /\ Y misses X \+\ Y let X, Y be ManySortedSet of I; ::_thesis: X /\ Y misses X \+\ Y now__::_thesis:_for_i_being_set_st_i_in_I_holds_ (X_/\_Y)_._i_misses_(X_\+\_Y)_._i let i be set ; ::_thesis: ( i in I implies (X /\ Y) . i misses (X \+\ Y) . i ) assume i in I ; ::_thesis: (X /\ Y) . i misses (X \+\ Y) . i then ( (X /\ Y) . i = (X . i) /\ (Y . i) & (X \+\ Y) . i = (X . i) \+\ (Y . i) ) by Def5, Th4; hence (X /\ Y) . i misses (X \+\ Y) . i by XBOOLE_1:103; ::_thesis: verum end; hence X /\ Y misses X \+\ Y by Def8; ::_thesis: verum end; theorem Th111: :: PBOOLE:111 for I being set for X, Y being ManySortedSet of I st X misses Y holds X /\ Y = [[0]] I proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X misses Y holds X /\ Y = [[0]] I let X, Y be ManySortedSet of I; ::_thesis: ( X misses Y implies X /\ Y = [[0]] I ) assume A1: X misses Y ; ::_thesis: X /\ Y = [[0]] I now__::_thesis:_for_i_being_set_st_i_in_I_holds_ (X_/\_Y)_._i_=_{} let i be set ; ::_thesis: ( i in I implies (X /\ Y) . i = {} ) assume A2: i in I ; ::_thesis: (X /\ Y) . i = {} then A3: X . i misses Y . i by A1, Def8; thus (X /\ Y) . i = (X . i) /\ (Y . i) by A2, Def5 .= {} by A3, XBOOLE_0:def_7 ; ::_thesis: verum end; hence X /\ Y = [[0]] I by Th6; ::_thesis: verum end; theorem :: PBOOLE:112 for I being set for X being ManySortedSet of I st X <> [[0]] I holds X meets X proof let I be set ; ::_thesis: for X being ManySortedSet of I st X <> [[0]] I holds X meets X let X be ManySortedSet of I; ::_thesis: ( X <> [[0]] I implies X meets X ) X = X /\ X ; hence ( X <> [[0]] I implies X meets X ) by Th111; ::_thesis: verum end; theorem :: PBOOLE:113 for I being set for X, Y, Z being ManySortedSet of I st X c= Y & X c= Z & Y misses Z holds X = [[0]] I proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X c= Y & X c= Z & Y misses Z holds X = [[0]] I let X, Y, Z be ManySortedSet of I; ::_thesis: ( X c= Y & X c= Z & Y misses Z implies X = [[0]] I ) assume A1: ( X c= Y & X c= Z ) ; ::_thesis: ( not Y misses Z or X = [[0]] I ) assume Y misses Z ; ::_thesis: X = [[0]] I then Y /\ Z = [[0]] I by Th111; hence X = [[0]] I by A1, Th17, Th44; ::_thesis: verum end; theorem :: PBOOLE:114 for I being set for Z, V, X, Y being ManySortedSet of I st Z \/ V = X \/ Y & X misses Z & Y misses V holds ( X = V & Y = Z ) proof let I be set ; ::_thesis: for Z, V, X, Y being ManySortedSet of I st Z \/ V = X \/ Y & X misses Z & Y misses V holds ( X = V & Y = Z ) let Z, V, X, Y be ManySortedSet of I; ::_thesis: ( Z \/ V = X \/ Y & X misses Z & Y misses V implies ( X = V & Y = Z ) ) assume A1: Z \/ V = X \/ Y ; ::_thesis: ( not X misses Z or not Y misses V or ( X = V & Y = Z ) ) assume ( X misses Z & Y misses V ) ; ::_thesis: ( X = V & Y = Z ) then A2: ( X /\ Z = [[0]] I & Y /\ V = [[0]] I ) by Th111; thus X = X /\ (Z \/ V) by Th23, A1, Th14 .= (X /\ Z) \/ (X /\ V) by Th32 .= (X \/ Y) /\ V by A2, Th32 .= V by A1, Th14, Th23 ; ::_thesis: Y = Z thus Y = Y /\ (Z \/ V) by Th23, A1, Th14 .= (Y /\ Z) \/ (Y /\ V) by Th32 .= (X \/ Y) /\ Z by A2, Th32 .= Z by A1, Th14, Th23 ; ::_thesis: verum end; theorem Th115: :: PBOOLE:115 for I being set for X, Y being ManySortedSet of I st X misses Y holds X \ Y = X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X misses Y holds X \ Y = X let X, Y be ManySortedSet of I; ::_thesis: ( X misses Y implies X \ Y = X ) assume A1: X misses Y ; ::_thesis: X \ Y = X let i be set ; :: according to PBOOLE:def_10 ::_thesis: ( i in I implies (X \ Y) . i = X . i ) assume A2: i in I ; ::_thesis: (X \ Y) . i = X . i then A3: (X \ Y) . i = (X . i) \ (Y . i) by Def6; X . i misses Y . i by A1, A2, Def8; hence (X \ Y) . i = X . i by A3, XBOOLE_1:83; ::_thesis: verum end; theorem :: PBOOLE:116 for I being set for X, Y being ManySortedSet of I st X misses Y holds (X \/ Y) \ Y = X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X misses Y holds (X \/ Y) \ Y = X let X, Y be ManySortedSet of I; ::_thesis: ( X misses Y implies (X \/ Y) \ Y = X ) (X \/ Y) \ Y = X \ Y by Th75; hence ( X misses Y implies (X \/ Y) \ Y = X ) by Th115; ::_thesis: verum end; theorem :: PBOOLE:117 for I being set for X, Y being ManySortedSet of I st X \ Y = X holds X misses Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X \ Y = X holds X misses Y let X, Y be ManySortedSet of I; ::_thesis: ( X \ Y = X implies X misses Y ) assume A1: X \ Y = X ; ::_thesis: X misses Y let i be set ; :: according to PBOOLE:def_8 ::_thesis: ( i in I implies X . i misses Y . i ) assume i in I ; ::_thesis: X . i misses Y . i then (X . i) \ (Y . i) = X . i by A1, Def6; hence X . i misses Y . i by XBOOLE_1:83; ::_thesis: verum end; theorem :: PBOOLE:118 for I being set for X, Y being ManySortedSet of I holds X \ Y misses Y \ X proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I holds X \ Y misses Y \ X let X, Y be ManySortedSet of I; ::_thesis: X \ Y misses Y \ X let i be set ; :: according to PBOOLE:def_8 ::_thesis: ( i in I implies (X \ Y) . i misses (Y \ X) . i ) assume i in I ; ::_thesis: (X \ Y) . i misses (Y \ X) . i then ( (X \ Y) . i = (X . i) \ (Y . i) & (Y \ X) . i = (Y . i) \ (X . i) ) by Def6; hence (X \ Y) . i misses (Y \ X) . i by XBOOLE_1:82; ::_thesis: verum end; begin definition let I be set ; let X, Y be ManySortedSet of I; predX [= Y means :Def11: :: PBOOLE:def 11 for x being ManySortedSet of I st x in X holds x in Y; reflexivity for X, x being ManySortedSet of I st x in X holds x in X ; end; :: deftheorem Def11 defines [= PBOOLE:def_11_:_ for I being set for X, Y being ManySortedSet of I holds ( X [= Y iff for x being ManySortedSet of I st x in X holds x in Y ); theorem :: PBOOLE:119 for I being set for X, Y being ManySortedSet of I st X c= Y holds X [= Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X c= Y holds X [= Y let X, Y be ManySortedSet of I; ::_thesis: ( X c= Y implies X [= Y ) assume A1: X c= Y ; ::_thesis: X [= Y let x be ManySortedSet of I; :: according to PBOOLE:def_11 ::_thesis: ( x in X implies x in Y ) assume A2: x in X ; ::_thesis: x in Y let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies x . i in Y . i ) assume A3: i in I ; ::_thesis: x . i in Y . i then A4: X . i c= Y . i by A1, Def2; x . i in X . i by A2, A3, Def1; hence x . i in Y . i by A4; ::_thesis: verum end; theorem :: PBOOLE:120 for I being set for X, Y, Z being ManySortedSet of I st X [= Y & Y [= Z holds X [= Z proof let I be set ; ::_thesis: for X, Y, Z being ManySortedSet of I st X [= Y & Y [= Z holds X [= Z let X, Y, Z be ManySortedSet of I; ::_thesis: ( X [= Y & Y [= Z implies X [= Z ) assume that A1: X [= Y and A2: Y [= Z ; ::_thesis: X [= Z let x be ManySortedSet of I; :: according to PBOOLE:def_11 ::_thesis: ( x in X implies x in Z ) assume x in X ; ::_thesis: x in Z then x in Y by A1, Def11; hence x in Z by A2, Def11; ::_thesis: verum end; begin theorem :: PBOOLE:121 [[0]] {} in [[0]] {} proof let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in {} implies ([[0]] {}) . i in ([[0]] {}) . i ) thus ( i in {} implies ([[0]] {}) . i in ([[0]] {}) . i ) ; ::_thesis: verum end; theorem :: PBOOLE:122 for X being ManySortedSet of {} holds X = {} proof let X be ManySortedSet of {} ; ::_thesis: X = {} dom X = {} by PARTFUN1:def_2; hence X = {} by RELAT_1:41; ::_thesis: verum end; theorem :: PBOOLE:123 for I being non empty set for X, Y being ManySortedSet of I st X overlaps Y holds X meets Y proof let I be non empty set ; ::_thesis: for X, Y being ManySortedSet of I st X overlaps Y holds X meets Y let X, Y be ManySortedSet of I; ::_thesis: ( X overlaps Y implies X meets Y ) set i = the Element of I; assume X overlaps Y ; ::_thesis: X meets Y then X . the Element of I meets Y . the Element of I by Def7; hence X meets Y by Def8; ::_thesis: verum end; theorem Th124: :: PBOOLE:124 for I being non empty set for x being ManySortedSet of I holds not x in [[0]] I proof let I be non empty set ; ::_thesis: for x being ManySortedSet of I holds not x in [[0]] I set i = the Element of I; given x being ManySortedSet of I such that A1: x in [[0]] I ; ::_thesis: contradiction x . the Element of I in ([[0]] I) . the Element of I by A1, Def1; hence contradiction by FUNCOP_1:7; ::_thesis: verum end; theorem :: PBOOLE:125 for I being non empty set for x, X, Y being ManySortedSet of I st x in X & x in Y holds X /\ Y <> [[0]] I proof let I be non empty set ; ::_thesis: for x, X, Y being ManySortedSet of I st x in X & x in Y holds X /\ Y <> [[0]] I let x, X, Y be ManySortedSet of I; ::_thesis: ( x in X & x in Y implies X /\ Y <> [[0]] I ) assume ( x in X & x in Y ) ; ::_thesis: X /\ Y <> [[0]] I then x in X /\ Y by Th8; hence X /\ Y <> [[0]] I by Th124; ::_thesis: verum end; theorem :: PBOOLE:126 for I being non empty set for X being ManySortedSet of I holds not X overlaps [[0]] I proof let I be non empty set ; ::_thesis: for X being ManySortedSet of I holds not X overlaps [[0]] I let X be ManySortedSet of I; ::_thesis: not X overlaps [[0]] I assume X overlaps [[0]] I ; ::_thesis: contradiction then ex x being ManySortedSet of I st ( x in X & x in [[0]] I ) by Th11; hence contradiction by Th124; ::_thesis: verum end; theorem Th127: :: PBOOLE:127 for I being non empty set for X, Y being ManySortedSet of I st X /\ Y = [[0]] I holds not X overlaps Y proof let I be non empty set ; ::_thesis: for X, Y being ManySortedSet of I st X /\ Y = [[0]] I holds not X overlaps Y let X, Y be ManySortedSet of I; ::_thesis: ( X /\ Y = [[0]] I implies not X overlaps Y ) assume A1: X /\ Y = [[0]] I ; ::_thesis: not X overlaps Y assume X overlaps Y ; ::_thesis: contradiction then consider x being ManySortedSet of I such that A2: ( x in X & x in Y ) by Th11; x in X /\ Y by A2, Th8; hence contradiction by A1, Th124; ::_thesis: verum end; theorem :: PBOOLE:128 for I being non empty set for X being ManySortedSet of I st X overlaps X holds X <> [[0]] I proof let I be non empty set ; ::_thesis: for X being ManySortedSet of I st X overlaps X holds X <> [[0]] I let X be ManySortedSet of I; ::_thesis: ( X overlaps X implies X <> [[0]] I ) X = X /\ X ; hence ( X overlaps X implies X <> [[0]] I ) by Th127; ::_thesis: verum end; begin definition let I be set ; let X be ManySortedSet of I; :: original: empty-yielding redefine attrX is empty-yielding means :: PBOOLE:def 12 for i being set st i in I holds X . i is empty ; compatibility ( X is empty-yielding iff for i being set st i in I holds X . i is empty ) proof dom X = I by PARTFUN1:def_2; hence ( X is empty-yielding iff for i being set st i in I holds X . i is empty ) by FUNCT_1:def_8; ::_thesis: verum end; :: original: non-empty redefine attrX is non-empty means :Def13: :: PBOOLE:def 13 for i being set st i in I holds not X . i is empty ; compatibility ( X is non-empty iff for i being set st i in I holds not X . i is empty ) proof dom X = I by PARTFUN1:def_2; hence ( X is non-empty iff for i being set st i in I holds not X . i is empty ) by FUNCT_1:def_9; ::_thesis: verum end; end; :: deftheorem defines empty-yielding PBOOLE:def_12_:_ for I being set for X being ManySortedSet of I holds ( X is empty-yielding iff for i being set st i in I holds X . i is empty ); :: deftheorem Def13 defines non-empty PBOOLE:def_13_:_ for I being set for X being ManySortedSet of I holds ( X is non-empty iff for i being set st i in I holds not X . i is empty ); registration let I be set ; cluster Relation-like V9() I -defined Function-like total for set ; existence not for b1 being ManySortedSet of I holds b1 is V9() proof take [[0]] I ; ::_thesis: [[0]] I is V9() let i be set ; :: according to PBOOLE:def_12 ::_thesis: ( i in I implies ([[0]] I) . i is empty ) assume i in I ; ::_thesis: ([[0]] I) . i is empty thus ([[0]] I) . i is empty by Th5; ::_thesis: verum end; cluster Relation-like V8() I -defined Function-like total for set ; existence not for b1 being ManySortedSet of I holds b1 is V8() proof set e = the set ; reconsider M = I --> { the set } as ManySortedSet of I ; take M ; ::_thesis: M is V8() let i be set ; :: according to PBOOLE:def_13 ::_thesis: ( i in I implies not M . i is empty ) assume i in I ; ::_thesis: not M . i is empty hence not M . i is empty by FUNCOP_1:7; ::_thesis: verum end; end; registration let I be non empty set ; cluster Relation-like V8() I -defined Function-like total -> V9() for set ; coherence for b1 being ManySortedSet of I st b1 is V8() holds not b1 is V9() proof set i = the Element of I; let M be ManySortedSet of I; ::_thesis: ( M is V8() implies not M is V9() ) assume A1: M is V8() ; ::_thesis: M is V9() take the Element of I ; :: according to PBOOLE:def_12 ::_thesis: ( the Element of I in I & not M . the Element of I is empty ) thus the Element of I in I ; ::_thesis: not M . the Element of I is empty thus not M . the Element of I is empty by A1, Def13; ::_thesis: verum end; cluster Relation-like V9() I -defined Function-like total -> V8() for set ; coherence for b1 being ManySortedSet of I st b1 is V9() holds not b1 is V8() ; end; theorem :: PBOOLE:129 for I being set for X being ManySortedSet of I holds ( X is V9() iff X = [[0]] I ) proof let I be set ; ::_thesis: for X being ManySortedSet of I holds ( X is V9() iff X = [[0]] I ) let X be ManySortedSet of I; ::_thesis: ( X is V9() iff X = [[0]] I ) hereby ::_thesis: ( X = [[0]] I implies X is V9() ) assume X is V9() ; ::_thesis: X = [[0]] I then for i being set st i in I holds X . i = {} ; hence X = [[0]] I by Th6; ::_thesis: verum end; assume A1: X = [[0]] I ; ::_thesis: X is V9() let i be set ; :: according to PBOOLE:def_12 ::_thesis: ( i in I implies X . i is empty ) assume i in I ; ::_thesis: X . i is empty thus X . i is empty by A1, Th5; ::_thesis: verum end; theorem :: PBOOLE:130 for I being set for Y, X being ManySortedSet of I st Y is V9() & X c= Y holds X is V9() proof let I be set ; ::_thesis: for Y, X being ManySortedSet of I st Y is V9() & X c= Y holds X is V9() let Y, X be ManySortedSet of I; ::_thesis: ( Y is V9() & X c= Y implies X is V9() ) assume A1: ( Y is V9() & X c= Y ) ; ::_thesis: X is V9() let i be set ; :: according to PBOOLE:def_12 ::_thesis: ( i in I implies X . i is empty ) assume i in I ; ::_thesis: X . i is empty then ( X . i c= Y . i & Y . i is empty ) by A1, Def2; hence X . i is empty by XBOOLE_1:3; ::_thesis: verum end; theorem Th131: :: PBOOLE:131 for I being set for X, Y being ManySortedSet of I st X is V8() & X c= Y holds Y is V8() proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X is V8() & X c= Y holds Y is V8() let X, Y be ManySortedSet of I; ::_thesis: ( X is V8() & X c= Y implies Y is V8() ) assume A1: ( X is V8() & X c= Y ) ; ::_thesis: Y is V8() let i be set ; :: according to PBOOLE:def_13 ::_thesis: ( i in I implies not Y . i is empty ) assume i in I ; ::_thesis: not Y . i is empty then ( X . i c= Y . i & not X . i is empty ) by A1, Def2, Def13; hence not Y . i is empty by XBOOLE_1:3; ::_thesis: verum end; theorem Th132: :: PBOOLE:132 for I being set for X, Y being ManySortedSet of I st X is V8() & X [= Y holds X c= Y proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X is V8() & X [= Y holds X c= Y let X, Y be ManySortedSet of I; ::_thesis: ( X is V8() & X [= Y implies X c= Y ) assume that A1: X is V8() and A2: X [= Y ; ::_thesis: X c= Y deffunc H1( set ) -> set = X . $1; A3: for i being set st i in I holds H1(i) <> {} by A1, Def13; consider f being ManySortedSet of I such that A4: for i being set st i in I holds f . i in H1(i) from PBOOLE:sch_1(A3); let i be set ; :: according to PBOOLE:def_2 ::_thesis: ( i in I implies X . i c= Y . i ) assume A5: i in I ; ::_thesis: X . i c= Y . i let e be set ; :: according to TARSKI:def_3 ::_thesis: ( not e in X . i or e in Y . i ) deffunc H2( set ) -> set = IFEQ (i,$1,e,(f . $1)); consider g being Function such that A6: dom g = I and A7: for u being set st u in I holds g . u = H2(u) from FUNCT_1:sch_3(); reconsider g = g as ManySortedSet of I by A6, PARTFUN1:def_2, RELAT_1:def_18; A8: g . i = IFEQ (i,i,e,(f . i)) by A5, A7 .= e by FUNCOP_1:def_8 ; assume A9: e in X . i ; ::_thesis: e in Y . i g in X proof let u be set ; :: according to PBOOLE:def_1 ::_thesis: ( u in I implies g . u in X . u ) assume A10: u in I ; ::_thesis: g . u in X . u percases ( u = i or u <> i ) ; suppose u = i ; ::_thesis: g . u in X . u hence g . u in X . u by A8, A9; ::_thesis: verum end; supposeA11: u <> i ; ::_thesis: g . u in X . u g . u = IFEQ (i,u,e,(f . u)) by A7, A10 .= f . u by A11, FUNCOP_1:def_8 ; hence g . u in X . u by A4, A10; ::_thesis: verum end; end; end; then g in Y by A2, Def11; hence e in Y . i by A5, A8, Def1; ::_thesis: verum end; theorem :: PBOOLE:133 for I being set for X, Y being ManySortedSet of I st X is V8() & X [= Y holds Y is V8() proof let I be set ; ::_thesis: for X, Y being ManySortedSet of I st X is V8() & X [= Y holds Y is V8() let X, Y be ManySortedSet of I; ::_thesis: ( X is V8() & X [= Y implies Y is V8() ) assume A1: X is V8() ; ::_thesis: ( not X [= Y or not Y is V8() ) assume X [= Y ; ::_thesis: Y is V8() then X c= Y by A1, Th132; hence Y is V8() by A1, Th131; ::_thesis: verum end; theorem :: PBOOLE:134 for I being set for X being V8() ManySortedSet of I ex x being ManySortedSet of I st x in X proof let I be set ; ::_thesis: for X being V8() ManySortedSet of I ex x being ManySortedSet of I st x in X let X be V8() ManySortedSet of I; ::_thesis: ex x being ManySortedSet of I st x in X deffunc H1( set ) -> set = X . $1; A1: for i being set st i in I holds H1(i) <> {} by Def13; consider f being ManySortedSet of I such that A2: for i being set st i in I holds f . i in H1(i) from PBOOLE:sch_1(A1); take f ; ::_thesis: f in X let i be set ; :: according to PBOOLE:def_1 ::_thesis: ( i in I implies f . i in X . i ) thus ( i in I implies f . i in X . i ) by A2; ::_thesis: verum end; theorem Th135: :: PBOOLE:135 for I being set for Y being ManySortedSet of I for X being V8() ManySortedSet of I st ( for x being ManySortedSet of I holds ( x in X iff x in Y ) ) holds X = Y proof let I be set ; ::_thesis: for Y being ManySortedSet of I for X being V8() ManySortedSet of I st ( for x being ManySortedSet of I holds ( x in X iff x in Y ) ) holds X = Y let Y be ManySortedSet of I; ::_thesis: for X being V8() ManySortedSet of I st ( for x being ManySortedSet of I holds ( x in X iff x in Y ) ) holds X = Y let X be V8() ManySortedSet of I; ::_thesis: ( ( for x being ManySortedSet of I holds ( x in X iff x in Y ) ) implies X = Y ) deffunc H1( set ) -> set = X . $1; A1: for i being set st i in I holds H1(i) <> {} by Def13; consider f being ManySortedSet of I such that A2: for i being set st i in I holds f . i in H1(i) from PBOOLE:sch_1(A1); assume A3: for x being ManySortedSet of I holds ( x in X iff x in Y ) ; ::_thesis: X = Y now__::_thesis:_for_i_being_set_st_i_in_I_holds_ X_._i_=_Y_._i let i be set ; ::_thesis: ( i in I implies X . i = Y . i ) assume A4: i in I ; ::_thesis: X . i = Y . i now__::_thesis:_for_e_being_set_holds_ (_(_e_in_X_._i_implies_e_in_Y_._i_)_&_(_e_in_Y_._i_implies_e_in_X_._i_)_) let e be set ; ::_thesis: ( ( e in X . i implies e in Y . i ) & ( e in Y . i implies e in X . i ) ) deffunc H2( set ) -> set = IFEQ (i,$1,e,(f . $1)); consider g being Function such that A5: dom g = I and A6: for u being set st u in I holds g . u = H2(u) from FUNCT_1:sch_3(); reconsider g = g as ManySortedSet of I by A5, PARTFUN1:def_2, RELAT_1:def_18; A7: g . i = IFEQ (i,i,e,(f . i)) by A4, A6 .= e by FUNCOP_1:def_8 ; hereby ::_thesis: ( e in Y . i implies e in X . i ) assume A8: e in X . i ; ::_thesis: e in Y . i g in X proof let u be set ; :: according to PBOOLE:def_1 ::_thesis: ( u in I implies g . u in X . u ) assume A9: u in I ; ::_thesis: g . u in X . u percases ( u = i or u <> i ) ; suppose u = i ; ::_thesis: g . u in X . u hence g . u in X . u by A7, A8; ::_thesis: verum end; supposeA10: u <> i ; ::_thesis: g . u in X . u g . u = IFEQ (i,u,e,(f . u)) by A6, A9 .= f . u by A10, FUNCOP_1:def_8 ; hence g . u in X . u by A2, A9; ::_thesis: verum end; end; end; then g in Y by A3; hence e in Y . i by A4, A7, Def1; ::_thesis: verum end; assume A11: e in Y . i ; ::_thesis: e in X . i g in Y proof let u be set ; :: according to PBOOLE:def_1 ::_thesis: ( u in I implies g . u in Y . u ) assume A12: u in I ; ::_thesis: g . u in Y . u percases ( u = i or u <> i ) ; suppose u = i ; ::_thesis: g . u in Y . u hence g . u in Y . u by A7, A11; ::_thesis: verum end; supposeA13: u <> i ; ::_thesis: g . u in Y . u f in X by A2, Def1; then A14: f in Y by A3; g . u = IFEQ (i,u,e,(f . u)) by A6, A12 .= f . u by A13, FUNCOP_1:def_8 ; hence g . u in Y . u by A12, A14, Def1; ::_thesis: verum end; end; end; then g in X by A3; hence e in X . i by A4, A7, Def1; ::_thesis: verum end; hence X . i = Y . i by TARSKI:1; ::_thesis: verum end; hence X = Y by Th3; ::_thesis: verum end; theorem :: PBOOLE:136 for I being set for Y, Z being ManySortedSet of I for X being V8() ManySortedSet of I st ( for x being ManySortedSet of I holds ( x in X iff ( x in Y & x in Z ) ) ) holds X = Y /\ Z proof let I be set ; ::_thesis: for Y, Z being ManySortedSet of I for X being V8() ManySortedSet of I st ( for x being ManySortedSet of I holds ( x in X iff ( x in Y & x in Z ) ) ) holds X = Y /\ Z let Y, Z be ManySortedSet of I; ::_thesis: for X being V8() ManySortedSet of I st ( for x being ManySortedSet of I holds ( x in X iff ( x in Y & x in Z ) ) ) holds X = Y /\ Z let X be V8() ManySortedSet of I; ::_thesis: ( ( for x being ManySortedSet of I holds ( x in X iff ( x in Y & x in Z ) ) ) implies X = Y /\ Z ) assume A1: for x being ManySortedSet of I holds ( x in X iff ( x in Y & x in Z ) ) ; ::_thesis: X = Y /\ Z now__::_thesis:_for_x_being_ManySortedSet_of_I_holds_ (_(_x_in_X_implies_x_in_Y_/\_Z_)_&_(_x_in_Y_/\_Z_implies_x_in_X_)_) let x be ManySortedSet of I; ::_thesis: ( ( x in X implies x in Y /\ Z ) & ( x in Y /\ Z implies x in X ) ) hereby ::_thesis: ( x in Y /\ Z implies x in X ) assume x in X ; ::_thesis: x in Y /\ Z then ( x in Y & x in Z ) by A1; hence x in Y /\ Z by Th8; ::_thesis: verum end; assume x in Y /\ Z ; ::_thesis: x in X then ( x in Y & x in Z ) by Th8; hence x in X by A1; ::_thesis: verum end; hence X = Y /\ Z by Th135; ::_thesis: verum end; begin scheme :: PBOOLE:sch 3 MSSEx{ F1() -> set , P1[ set , set ] } : ex f being ManySortedSet of F1() st for i being set st i in F1() holds P1[i,f . i] provided A1: for i being set st i in F1() holds ex j being set st P1[i,j] proof A2: for i being set st i in F1() holds ex j being set st P1[i,j] by A1; consider f being Function such that A3: dom f = F1() and A4: for i being set st i in F1() holds P1[i,f . i] from CLASSES1:sch_1(A2); reconsider f = f as ManySortedSet of F1() by A3, PARTFUN1:def_2, RELAT_1:def_18; take f ; ::_thesis: for i being set st i in F1() holds P1[i,f . i] thus for i being set st i in F1() holds P1[i,f . i] by A4; ::_thesis: verum end; scheme :: PBOOLE:sch 4 MSSLambda{ F1() -> set , F2( set ) -> set } : ex f being ManySortedSet of F1() st for i being set st i in F1() holds f . i = F2(i) proof consider f being Function such that A1: dom f = F1() and A2: for i being set st i in F1() holds f . i = F2(i) from FUNCT_1:sch_3(); reconsider f = f as ManySortedSet of F1() by A1, PARTFUN1:def_2, RELAT_1:def_18; take f ; ::_thesis: for i being set st i in F1() holds f . i = F2(i) thus for i being set st i in F1() holds f . i = F2(i) by A2; ::_thesis: verum end; registration let I be set ; cluster Relation-like I -defined Function-like total Function-yielding for set ; existence ex b1 being ManySortedSet of I st b1 is Function-yielding proof set f = the Function; reconsider F = I --> the Function as ManySortedSet of I ; take F ; ::_thesis: F is Function-yielding let x be set ; :: according to FUNCOP_1:def_6 ::_thesis: ( not x in dom F or F . x is set ) assume x in dom F ; ::_thesis: F . x is set thus F . x is set ; ::_thesis: verum end; end; definition let I be set ; mode ManySortedFunction of I is Function-yielding ManySortedSet of I; end; theorem :: PBOOLE:137 for I being set for M being V8() ManySortedSet of I holds not {} in rng M proof let I be set ; ::_thesis: for M being V8() ManySortedSet of I holds not {} in rng M let M be V8() ManySortedSet of I; ::_thesis: not {} in rng M A1: dom M = I by PARTFUN1:def_2; assume {} in rng M ; ::_thesis: contradiction then ex i being set st ( i in I & M . i = {} ) by A1, FUNCT_1:def_3; hence contradiction by Def13; ::_thesis: verum end; definition let I be set ; let M be ManySortedSet of I; mode Component of M is Element of rng M; end; theorem :: PBOOLE:138 for I being non empty set for M being ManySortedSet of I for A being Component of M ex i being set st ( i in I & A = M . i ) proof let I be non empty set ; ::_thesis: for M being ManySortedSet of I for A being Component of M ex i being set st ( i in I & A = M . i ) let M be ManySortedSet of I; ::_thesis: for A being Component of M ex i being set st ( i in I & A = M . i ) let A be Component of M; ::_thesis: ex i being set st ( i in I & A = M . i ) A1: dom M = I by PARTFUN1:def_2; then rng M <> {} by RELAT_1:42; hence ex i being set st ( i in I & A = M . i ) by A1, FUNCT_1:def_3; ::_thesis: verum end; theorem :: PBOOLE:139 for I being set for M being ManySortedSet of I for i being set st i in I holds M . i is Component of M proof let I be set ; ::_thesis: for M being ManySortedSet of I for i being set st i in I holds M . i is Component of M let M be ManySortedSet of I; ::_thesis: for i being set st i in I holds M . i is Component of M let i be set ; ::_thesis: ( i in I implies M . i is Component of M ) assume A1: i in I ; ::_thesis: M . i is Component of M dom M = I by PARTFUN1:def_2; hence M . i is Component of M by A1, FUNCT_1:def_3; ::_thesis: verum end; definition let I be set ; let B be ManySortedSet of I; mode Element of B -> ManySortedSet of I means :: PBOOLE:def 14 for i being set st i in I holds it . i is Element of B . i; existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i is Element of B . i proof defpred S1[ set , set ] means $2 is Element of B . $1; A1: for i being set st i in I holds ex j being set st S1[i,j] proof let i be set ; ::_thesis: ( i in I implies ex j being set st S1[i,j] ) assume i in I ; ::_thesis: ex j being set st S1[i,j] set j = the Element of B . i; reconsider j = the Element of B . i as set ; take j ; ::_thesis: S1[i,j] thus S1[i,j] ; ::_thesis: verum end; thus ex f being ManySortedSet of I st for i being set st i in I holds S1[i,f . i] from PBOOLE:sch_3(A1); ::_thesis: verum end; end; :: deftheorem defines Element PBOOLE:def_14_:_ for I being set for B, b3 being ManySortedSet of I holds ( b3 is Element of B iff for i being set st i in I holds b3 . i is Element of B . i ); begin definition let I be set ; let A, B be ManySortedSet of I; mode ManySortedFunction of A,B -> ManySortedSet of I means :Def15: :: PBOOLE:def 15 for i being set st i in I holds it . i is Function of (A . i),(B . i); correctness existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i is Function of (A . i),(B . i); proof defpred S1[ set , set ] means $2 is Function of (A . $1),(B . $1); A1: for i being set st i in I holds ex j being set st S1[i,j] proof let i be set ; ::_thesis: ( i in I implies ex j being set st S1[i,j] ) assume i in I ; ::_thesis: ex j being set st S1[i,j] set j = the Function of (A . i),(B . i); reconsider j = the Function of (A . i),(B . i) as set ; take j ; ::_thesis: S1[i,j] thus S1[i,j] ; ::_thesis: verum end; consider f being ManySortedSet of I such that A2: for i being set st i in I holds S1[i,f . i] from PBOOLE:sch_3(A1); f is Function-yielding proof let i be set ; :: according to FUNCOP_1:def_6 ::_thesis: ( not i in dom f or f . i is set ) assume i in dom f ; ::_thesis: f . i is set then i in I by PARTFUN1:def_2; hence f . i is set by A2; ::_thesis: verum end; then reconsider f = f as ManySortedFunction of I ; take f ; ::_thesis: for i being set st i in I holds f . i is Function of (A . i),(B . i) let i be set ; ::_thesis: ( i in I implies f . i is Function of (A . i),(B . i) ) assume i in I ; ::_thesis: f . i is Function of (A . i),(B . i) hence f . i is Function of (A . i),(B . i) by A2; ::_thesis: verum end; end; :: deftheorem Def15 defines ManySortedFunction PBOOLE:def_15_:_ for I being set for A, B, b4 being ManySortedSet of I holds ( b4 is ManySortedFunction of A,B iff for i being set st i in I holds b4 . i is Function of (A . i),(B . i) ); registration let I be set ; let A, B be ManySortedSet of I; cluster -> Function-yielding for ManySortedFunction of A,B; coherence for b1 being ManySortedFunction of A,B holds b1 is Function-yielding proof let f be ManySortedFunction of A,B; ::_thesis: f is Function-yielding let i be set ; :: according to FUNCOP_1:def_6 ::_thesis: ( not i in dom f or f . i is set ) assume i in dom f ; ::_thesis: f . i is set then i in I by PARTFUN1:def_2; hence f . i is set by Def15; ::_thesis: verum end; end; registration let I be set ; let J be non empty set ; let O be Function of I,J; let F be ManySortedSet of J; clusterO * F -> I -defined total for I -defined Function; coherence for b1 being I -defined Function st b1 = F * O holds b1 is total proof A1: dom F = J by PARTFUN1:def_2; ( rng O c= J & dom O = I ) by FUNCT_2:def_1, RELAT_1:def_19; then dom (F * O) = I by A1, RELAT_1:27; hence for b1 being I -defined Function st b1 = F * O holds b1 is total by PARTFUN1:def_2; ::_thesis: verum end; end; scheme :: PBOOLE:sch 5 LambdaDMS{ F1() -> non empty set , F2( set ) -> set } : ex X being ManySortedSet of F1() st for d being Element of F1() holds X . d = F2(d) proof consider f being Function such that A1: dom f = F1() and A2: for d being Element of F1() holds f . d = F2(d) from FUNCT_1:sch_4(); f is ManySortedSet of F1() by A1, PARTFUN1:def_2, RELAT_1:def_18; hence ex X being ManySortedSet of F1() st for d being Element of F1() holds X . d = F2(d) by A2; ::_thesis: verum end; registration let J be non empty set ; let B be V8() ManySortedSet of J; let j be Element of J; clusterB . j -> non empty ; coherence not B . j is empty by Def13; end; definition let I be set ; let X, Y be ManySortedSet of I; func[|X,Y|] -> ManySortedSet of I means :: PBOOLE:def 16 for i being set st i in I holds it . i = [:(X . i),(Y . i):]; existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = [:(X . i),(Y . i):] proof deffunc H1( set ) -> set = [:(X . $1),(Y . $1):]; consider f being Function such that A1: ( dom f = I & ( for i being set st i in I holds f . i = H1(i) ) ) from FUNCT_1:sch_3(); reconsider f = f as ManySortedSet of I by A1, PARTFUN1:def_2, RELAT_1:def_18; take f ; ::_thesis: for i being set st i in I holds f . i = [:(X . i),(Y . i):] thus for i being set st i in I holds f . i = [:(X . i),(Y . i):] by A1; ::_thesis: verum end; uniqueness for b1, b2 being ManySortedSet of I st ( for i being set st i in I holds b1 . i = [:(X . i),(Y . i):] ) & ( for i being set st i in I holds b2 . i = [:(X . i),(Y . i):] ) holds b1 = b2 proof let f, g be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds f . i = [:(X . i),(Y . i):] ) & ( for i being set st i in I holds g . i = [:(X . i),(Y . i):] ) implies f = g ) assume that A2: for i being set st i in I holds f . i = [:(X . i),(Y . i):] and A3: for i being set st i in I holds g . i = [:(X . i),(Y . i):] ; ::_thesis: f = g for x being set st x in I holds f . x = g . x proof let x be set ; ::_thesis: ( x in I implies f . x = g . x ) assume A4: x in I ; ::_thesis: f . x = g . x then f . x = [:(X . x),(Y . x):] by A2; hence f . x = g . x by A3, A4; ::_thesis: verum end; hence f = g by Th3; ::_thesis: verum end; end; :: deftheorem defines [| PBOOLE:def_16_:_ for I being set for X, Y, b4 being ManySortedSet of I holds ( b4 = [|X,Y|] iff for i being set st i in I holds b4 . i = [:(X . i),(Y . i):] ); definition let I be set ; let X, Y be ManySortedSet of I; deffunc H1( set ) -> set = Funcs ((X . $1),(Y . $1)); func (Funcs) (X,Y) -> ManySortedSet of I means :: PBOOLE:def 17 for i being set st i in I holds it . i = Funcs ((X . i),(Y . i)); existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = Funcs ((X . i),(Y . i)) proof thus ex M being ManySortedSet of I st for i being set st i in I holds M . i = H1(i) from PBOOLE:sch_4(); ::_thesis: verum end; uniqueness for b1, b2 being ManySortedSet of I st ( for i being set st i in I holds b1 . i = Funcs ((X . i),(Y . i)) ) & ( for i being set st i in I holds b2 . i = Funcs ((X . i),(Y . i)) ) holds b1 = b2 proof let F1, F2 be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds F1 . i = Funcs ((X . i),(Y . i)) ) & ( for i being set st i in I holds F2 . i = Funcs ((X . i),(Y . i)) ) implies F1 = F2 ) assume that A1: for i being set st i in I holds F1 . i = Funcs ((X . i),(Y . i)) and A2: for i being set st i in I holds F2 . i = Funcs ((X . i),(Y . i)) ; ::_thesis: F1 = F2 now__::_thesis:_for_i_being_set_st_i_in_I_holds_ F1_._i_=_F2_._i let i be set ; ::_thesis: ( i in I implies F1 . i = F2 . i ) assume A3: i in I ; ::_thesis: F1 . i = F2 . i hence F1 . i = Funcs ((X . i),(Y . i)) by A1 .= F2 . i by A2, A3 ; ::_thesis: verum end; hence F1 = F2 by Th3; ::_thesis: verum end; end; :: deftheorem defines (Funcs) PBOOLE:def_17_:_ for I being set for X, Y, b4 being ManySortedSet of I holds ( b4 = (Funcs) (X,Y) iff for i being set st i in I holds b4 . i = Funcs ((X . i),(Y . i)) ); definition let I be set ; let M be ManySortedSet of I; mode ManySortedSubset of M -> ManySortedSet of I means :Def18: :: PBOOLE:def 18 it c= M; existence ex b1 being ManySortedSet of I st b1 c= M ; end; :: deftheorem Def18 defines ManySortedSubset PBOOLE:def_18_:_ for I being set for M, b3 being ManySortedSet of I holds ( b3 is ManySortedSubset of M iff b3 c= M ); registration let I be set ; let M be V8() ManySortedSet of I; cluster Relation-like V8() I -defined Function-like total for ManySortedSubset of M; existence not for b1 being ManySortedSubset of M holds b1 is V8() proof reconsider N = M as ManySortedSubset of M by Def18; take N ; ::_thesis: N is V8() thus N is V8() ; ::_thesis: verum end; end; definition let F, G be Function-yielding Function; funcG ** F -> Function means :Def19: :: PBOOLE:def 19 ( dom it = (dom F) /\ (dom G) & ( for i being set st i in dom it holds it . i = (G . i) * (F . i) ) ); existence ex b1 being Function st ( dom b1 = (dom F) /\ (dom G) & ( for i being set st i in dom b1 holds b1 . i = (G . i) * (F . i) ) ) proof defpred S1[ set , set ] means $2 = (G . $1) * (F . $1); A1: for i being set st i in (dom F) /\ (dom G) holds ex u being set st S1[i,u] ; ex H being Function st ( dom H = (dom F) /\ (dom G) & ( for i being set st i in (dom F) /\ (dom G) holds S1[i,H . i] ) ) from CLASSES1:sch_1(A1); hence ex b1 being Function st ( dom b1 = (dom F) /\ (dom G) & ( for i being set st i in dom b1 holds b1 . i = (G . i) * (F . i) ) ) ; ::_thesis: verum end; uniqueness for b1, b2 being Function st dom b1 = (dom F) /\ (dom G) & ( for i being set st i in dom b1 holds b1 . i = (G . i) * (F . i) ) & dom b2 = (dom F) /\ (dom G) & ( for i being set st i in dom b2 holds b2 . i = (G . i) * (F . i) ) holds b1 = b2 proof let H1, H2 be Function; ::_thesis: ( dom H1 = (dom F) /\ (dom G) & ( for i being set st i in dom H1 holds H1 . i = (G . i) * (F . i) ) & dom H2 = (dom F) /\ (dom G) & ( for i being set st i in dom H2 holds H2 . i = (G . i) * (F . i) ) implies H1 = H2 ) assume that A2: dom H1 = (dom F) /\ (dom G) and A3: for i being set st i in dom H1 holds H1 . i = (G . i) * (F . i) and A4: dom H2 = (dom F) /\ (dom G) and A5: for i being set st i in dom H2 holds H2 . i = (G . i) * (F . i) ; ::_thesis: H1 = H2 now__::_thesis:_for_i_being_set_st_i_in_(dom_F)_/\_(dom_G)_holds_ H1_._i_=_H2_._i let i be set ; ::_thesis: ( i in (dom F) /\ (dom G) implies H1 . i = H2 . i ) reconsider f = F . i as Function ; reconsider g = G . i as Function ; assume A6: i in (dom F) /\ (dom G) ; ::_thesis: H1 . i = H2 . i then H1 . i = g * f by A2, A3; hence H1 . i = H2 . i by A4, A5, A6; ::_thesis: verum end; hence H1 = H2 by A2, A4, FUNCT_1:2; ::_thesis: verum end; end; :: deftheorem Def19 defines ** PBOOLE:def_19_:_ for F, G being Function-yielding Function for b3 being Function holds ( b3 = G ** F iff ( dom b3 = (dom F) /\ (dom G) & ( for i being set st i in dom b3 holds b3 . i = (G . i) * (F . i) ) ) ); registration let F, G be Function-yielding Function; clusterG ** F -> Function-yielding ; coherence G ** F is Function-yielding proof set H = G ** F; let x be set ; :: according to FUNCOP_1:def_6 ::_thesis: ( not x in dom (G ** F) or (G ** F) . x is set ) reconsider f = F . x as Function ; reconsider g = G . x as Function ; assume x in dom (G ** F) ; ::_thesis: (G ** F) . x is set then (G ** F) . x = g * f by Def19; hence (G ** F) . x is set ; ::_thesis: verum end; end; definition let I be set ; let A be ManySortedSet of I; let F be ManySortedFunction of I; funcF .:.: A -> ManySortedSet of I means :: PBOOLE:def 20 for i being set st i in I holds it . i = (F . i) .: (A . i); existence ex b1 being ManySortedSet of I st for i being set st i in I holds b1 . i = (F . i) .: (A . i) proof defpred S1[ set , set ] means $2 = (F . $1) .: (A . $1); A1: for i being set st i in I holds ex u being set st S1[i,u] ; consider g being Function such that A2: ( dom g = I & ( for i being set st i in I holds S1[i,g . i] ) ) from CLASSES1:sch_1(A1); reconsider g = g as ManySortedSet of I by A2, PARTFUN1:def_2, RELAT_1:def_18; take g ; ::_thesis: for i being set st i in I holds g . i = (F . i) .: (A . i) thus for i being set st i in I holds g . i = (F . i) .: (A . i) by A2; ::_thesis: verum end; uniqueness for b1, b2 being ManySortedSet of I st ( for i being set st i in I holds b1 . i = (F . i) .: (A . i) ) & ( for i being set st i in I holds b2 . i = (F . i) .: (A . i) ) holds b1 = b2 proof let B, B1 be ManySortedSet of I; ::_thesis: ( ( for i being set st i in I holds B . i = (F . i) .: (A . i) ) & ( for i being set st i in I holds B1 . i = (F . i) .: (A . i) ) implies B = B1 ) assume that A3: for i being set st i in I holds B . i = (F . i) .: (A . i) and A4: for i being set st i in I holds B1 . i = (F . i) .: (A . i) ; ::_thesis: B = B1 now__::_thesis:_for_i_being_set_st_i_in_I_holds_ B_._i_=_B1_._i let i be set ; ::_thesis: ( i in I implies B . i = B1 . i ) reconsider f = F . i as Function ; assume A5: i in I ; ::_thesis: B . i = B1 . i then B . i = f .: (A . i) by A3; hence B . i = B1 . i by A4, A5; ::_thesis: verum end; hence B = B1 by Th3; ::_thesis: verum end; end; :: deftheorem defines .:.: PBOOLE:def_20_:_ for I being set for A being ManySortedSet of I for F being ManySortedFunction of I for b4 being ManySortedSet of I holds ( b4 = F .:.: A iff for i being set st i in I holds b4 . i = (F . i) .: (A . i) ); registration let I be set ; cluster [[0]] I -> V9() ; coherence [[0]] I is empty-yielding proof rng ([[0]] I) c= {{}} by FUNCOP_1:13; hence [[0]] I is empty-yielding by RELAT_1:def_15; ::_thesis: verum end; end; scheme :: PBOOLE:sch 6 MSSExD{ F1() -> non empty set , P1[ set , set ] } : ex f being ManySortedSet of F1() st for i being Element of F1() holds P1[i,f . i] provided A1: for i being Element of F1() ex j being set st P1[i,j] proof defpred S1[ set , set ] means P1[$1,$2]; A2: for i being set st i in F1() holds ex j being set st S1[i,j] by A1; consider f being ManySortedSet of F1() such that A3: for i being set st i in F1() holds S1[i,f . i] from PBOOLE:sch_3(A2); take f ; ::_thesis: for i being Element of F1() holds P1[i,f . i] let i be Element of F1(); ::_thesis: P1[i,f . i] thus P1[i,f . i] by A3; ::_thesis: verum end; registration let A be non empty set ; cluster Relation-like V8() A -defined Function-like total -> V9() for set ; coherence for b1 being ManySortedSet of A st b1 is V8() holds not b1 is V9() ; end; registration let X be non empty set ; cluster Relation-like X -defined Function-like total -> non empty for set ; coherence for b1 being ManySortedSet of X holds not b1 is empty proof set x = the Element of X; let f be ManySortedSet of X; ::_thesis: not f is empty dom f = X by PARTFUN1:def_2; then [ the Element of X,(f . the Element of X)] in f by FUNCT_1:def_2; hence not f is empty ; ::_thesis: verum end; end; theorem :: PBOOLE:140 for F, G, H being Function-yielding Function holds (H ** G) ** F = H ** (G ** F) proof let F, G, H be Function-yielding Function; ::_thesis: (H ** G) ** F = H ** (G ** F) set f = (H ** G) ** F; set g = H ** (G ** F); now__::_thesis:_(_dom_((H_**_G)_**_F)_=_dom_(H_**_(G_**_F))_&_(_for_x_being_set_st_x_in_dom_((H_**_G)_**_F)_holds_ ((H_**_G)_**_F)_._x_=_(H_**_(G_**_F))_._x_)_) A1: dom ((H ** G) ** F) = (dom (H ** G)) /\ (dom F) by Def19 .= ((dom H) /\ (dom G)) /\ (dom F) by Def19 ; then A2: dom ((H ** G) ** F) = (dom H) /\ ((dom G) /\ (dom F)) by XBOOLE_1:16; hence A3: dom ((H ** G) ** F) = (dom H) /\ (dom (G ** F)) by Def19 .= dom (H ** (G ** F)) by Def19 ; ::_thesis: for x being set st x in dom ((H ** G) ** F) holds ((H ** G) ** F) . x = (H ** (G ** F)) . x let x be set ; ::_thesis: ( x in dom ((H ** G) ** F) implies ((H ** G) ** F) . x = (H ** (G ** F)) . x ) assume A4: x in dom ((H ** G) ** F) ; ::_thesis: ((H ** G) ** F) . x = (H ** (G ** F)) . x then x in (dom H) /\ (dom G) by A1, XBOOLE_0:def_4; then A5: x in dom (H ** G) by Def19; x in (dom G) /\ (dom F) by A2, A4, XBOOLE_0:def_4; then A6: x in dom (G ** F) by Def19; thus ((H ** G) ** F) . x = ((H ** G) . x) * (F . x) by A4, Def19 .= ((H . x) * (G . x)) * (F . x) by A5, Def19 .= (H . x) * ((G . x) * (F . x)) by RELAT_1:36 .= (H . x) * ((G ** F) . x) by A6, Def19 .= (H ** (G ** F)) . x by A3, A4, Def19 ; ::_thesis: verum end; hence (H ** G) ** F = H ** (G ** F) by FUNCT_1:2; ::_thesis: verum end; registration let I be set ; let f be V8() ManySortedSet of I; cluster Relation-like I -defined Function-like f -compatible total for set ; existence ex b1 being I -defined f -compatible Function st b1 is total proof deffunc H1( set ) -> set = f . I; A1: for e being set st e in I holds H1(e) <> {} ; consider g being ManySortedSet of I such that A2: for e being set st e in I holds g . e in H1(e) from PBOOLE:sch_1(A1); g is f -compatible proof let x be set ; :: according to FUNCT_1:def_14 ::_thesis: ( not x in dom g or g . x in f . x ) assume x in dom g ; ::_thesis: g . x in f . x then x in I by PARTFUN1:def_2; hence g . x in f . x by A2; ::_thesis: verum end; then reconsider g = g as I -defined f -compatible Function ; take g ; ::_thesis: g is total thus g is total ; ::_thesis: verum end; end; theorem :: PBOOLE:141 for I being set for f being V8() ManySortedSet of I for p being b1 -defined b2 -compatible Function ex s being b2 -compatible ManySortedSet of I st p c= s proof let I be set ; ::_thesis: for f being V8() ManySortedSet of I for p being I -defined b1 -compatible Function ex s being b1 -compatible ManySortedSet of I st p c= s let f be V8() ManySortedSet of I; ::_thesis: for p being I -defined f -compatible Function ex s being f -compatible ManySortedSet of I st p c= s let p be I -defined f -compatible Function; ::_thesis: ex s being f -compatible ManySortedSet of I st p c= s set h = the f -compatible ManySortedSet of I; take the f -compatible ManySortedSet of I +* p ; ::_thesis: p c= the f -compatible ManySortedSet of I +* p thus p c= the f -compatible ManySortedSet of I +* p by FUNCT_4:25; ::_thesis: verum end; theorem :: PBOOLE:142 for I, A being set for s, ss being ManySortedSet of I holds (ss +* (s | A)) | A = s | A proof let I, A be set ; ::_thesis: for s, ss being ManySortedSet of I holds (ss +* (s | A)) | A = s | A let s, ss be ManySortedSet of I; ::_thesis: (ss +* (s | A)) | A = s | A dom s = I by PARTFUN1:def_2 .= dom ss by PARTFUN1:def_2 ; then A /\ (dom ss) c= A /\ (dom s) ; hence (ss +* (s | A)) | A = s | A by FUNCT_4:88; ::_thesis: verum end; registration let X be non empty set ; let Y be set ; cluster Relation-like Y -defined X -valued Function-like total for set ; existence ex b1 being ManySortedSet of Y st b1 is X -valued proof take M = Y --> the Element of X; ::_thesis: M is X -valued A1: { the Element of X} c= X by ZFMISC_1:31; rng M c= { the Element of X} by FUNCOP_1:13; hence rng M c= X by A1, XBOOLE_1:1; :: according to RELAT_1:def_19 ::_thesis: verum end; end; theorem :: PBOOLE:143 for I, Y being non empty set for M being b2 -valued ManySortedSet of I for x being Element of I holds M . x = M /. x proof let I, Y be non empty set ; ::_thesis: for M being Y -valued ManySortedSet of I for x being Element of I holds M . x = M /. x let M be Y -valued ManySortedSet of I; ::_thesis: for x being Element of I holds M . x = M /. x let x be Element of I; ::_thesis: M . x = M /. x dom M = I by PARTFUN1:def_2; hence M . x = M /. x by PARTFUN1:def_6; ::_thesis: verum end; theorem :: PBOOLE:144 for I being set for f being Function for M being ManySortedSet of I holds (f +* M) | I = M proof let I be set ; ::_thesis: for f being Function for M being ManySortedSet of I holds (f +* M) | I = M let f be Function; ::_thesis: for M being ManySortedSet of I holds (f +* M) | I = M let M be ManySortedSet of I; ::_thesis: (f +* M) | I = M A1: dom (f | I) c= I by RELAT_1:58; A2: dom M = I by PARTFUN1:def_2; thus (f +* M) | I = (f | I) +* (M | I) by FUNCT_4:71 .= (f | I) +* M by A2, RELAT_1:69 .= M by A1, A2, FUNCT_4:19 ; ::_thesis: verum end; theorem :: PBOOLE:145 for I being set for Y being non empty set for p being b1 -defined b2 -valued Function ex s being b2 -valued ManySortedSet of I st p c= s proof let I be set ; ::_thesis: for Y being non empty set for p being I -defined b1 -valued Function ex s being b1 -valued ManySortedSet of I st p c= s let Y be non empty set ; ::_thesis: for p being I -defined Y -valued Function ex s being Y -valued ManySortedSet of I st p c= s let p be I -defined Y -valued Function; ::_thesis: ex s being Y -valued ManySortedSet of I st p c= s set h = the Y -valued ManySortedSet of I; take the Y -valued ManySortedSet of I +* p ; ::_thesis: p c= the Y -valued ManySortedSet of I +* p thus p c= the Y -valued ManySortedSet of I +* p by FUNCT_4:25; ::_thesis: verum end; theorem :: PBOOLE:146 for I being set for X, Y being ManySortedSet of I st X c= Y & Y c= X holds X = Y by Lm1; definition let I be non empty set ; let A, B be ManySortedSet of I; :: original: = redefine predA = B means :: PBOOLE:def 21 for i being Element of I holds A . i = B . i; compatibility ( A = B iff for i being Element of I holds A . i = B . i ) proof thus ( A = B implies for i being Element of I holds A . i = B . i ) ; ::_thesis: ( ( for i being Element of I holds A . i = B . i ) implies A = B ) assume for i being Element of I holds A . i = B . i ; ::_thesis: A = B then for i being set st i in I holds A . i = B . i ; hence A = B by Th3; ::_thesis: verum end; end; :: deftheorem defines = PBOOLE:def_21_:_ for I being non empty set for A, B being ManySortedSet of I holds ( A = B iff for i being Element of I holds A . i = B . i );