| Step | Hyp | Ref | Expression | 
						
							| 1 |  | eqeq1 |  |-  ( p = <. x , y >. -> ( p = <. a , b >. <-> <. x , y >. = <. a , b >. ) ) | 
						
							| 2 | 1 | anbi1d |  |-  ( p = <. x , y >. -> ( ( p = <. a , b >. /\ ph ) <-> ( <. x , y >. = <. a , b >. /\ ph ) ) ) | 
						
							| 3 | 2 | 2exbidv |  |-  ( p = <. x , y >. -> ( E. a E. b ( p = <. a , b >. /\ ph ) <-> E. a E. b ( <. x , y >. = <. a , b >. /\ ph ) ) ) | 
						
							| 4 |  | eqeq1 |  |-  ( p = <. v , w >. -> ( p = <. a , b >. <-> <. v , w >. = <. a , b >. ) ) | 
						
							| 5 | 4 | anbi1d |  |-  ( p = <. v , w >. -> ( ( p = <. a , b >. /\ ph ) <-> ( <. v , w >. = <. a , b >. /\ ph ) ) ) | 
						
							| 6 | 5 | 2exbidv |  |-  ( p = <. v , w >. -> ( E. a E. b ( p = <. a , b >. /\ ph ) <-> E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) ) ) | 
						
							| 7 | 3 6 | reuop |  |-  ( E! p e. ( X X. X ) E. a E. b ( p = <. a , b >. /\ ph ) <-> E. x e. X E. y e. X ( E. a E. b ( <. x , y >. = <. a , b >. /\ ph ) /\ A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) ) ) | 
						
							| 8 |  | nfich1 |  |-  F/ a [ a <> b ] ph | 
						
							| 9 |  | nfv |  |-  F/ a ( x e. X /\ y e. X ) | 
						
							| 10 | 8 9 | nfan |  |-  F/ a ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) | 
						
							| 11 |  | nfcv |  |-  F/_ a X | 
						
							| 12 |  | nfe1 |  |-  F/ a E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) | 
						
							| 13 |  | nfv |  |-  F/ a <. v , w >. = <. x , y >. | 
						
							| 14 | 12 13 | nfim |  |-  F/ a ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) | 
						
							| 15 | 11 14 | nfralw |  |-  F/ a A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) | 
						
							| 16 | 11 15 | nfralw |  |-  F/ a A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) | 
						
							| 17 |  | nfe1 |  |-  F/ a E. a E. b ( a = b /\ ph ) | 
						
							| 18 | 16 17 | nfim |  |-  F/ a ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) | 
						
							| 19 |  | nfich2 |  |-  F/ b [ a <> b ] ph | 
						
							| 20 |  | nfv |  |-  F/ b ( x e. X /\ y e. X ) | 
						
							| 21 | 19 20 | nfan |  |-  F/ b ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) | 
						
							| 22 |  | nfcv |  |-  F/_ b X | 
						
							| 23 |  | nfe1 |  |-  F/ b E. b ( <. v , w >. = <. a , b >. /\ ph ) | 
						
							| 24 | 23 | nfex |  |-  F/ b E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) | 
						
							| 25 |  | nfv |  |-  F/ b <. v , w >. = <. x , y >. | 
						
							| 26 | 24 25 | nfim |  |-  F/ b ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) | 
						
							| 27 | 22 26 | nfralw |  |-  F/ b A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) | 
						
							| 28 | 22 27 | nfralw |  |-  F/ b A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) | 
						
							| 29 |  | nfe1 |  |-  F/ b E. b ( a = b /\ ph ) | 
						
							| 30 | 29 | nfex |  |-  F/ b E. a E. b ( a = b /\ ph ) | 
						
							| 31 | 28 30 | nfim |  |-  F/ b ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) | 
						
							| 32 |  | opeq12 |  |-  ( ( v = y /\ w = x ) -> <. v , w >. = <. y , x >. ) | 
						
							| 33 | 32 | eqeq1d |  |-  ( ( v = y /\ w = x ) -> ( <. v , w >. = <. a , b >. <-> <. y , x >. = <. a , b >. ) ) | 
						
							| 34 | 33 | anbi1d |  |-  ( ( v = y /\ w = x ) -> ( ( <. v , w >. = <. a , b >. /\ ph ) <-> ( <. y , x >. = <. a , b >. /\ ph ) ) ) | 
						
							| 35 | 34 | 2exbidv |  |-  ( ( v = y /\ w = x ) -> ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) <-> E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) ) ) | 
						
							| 36 | 32 | eqeq1d |  |-  ( ( v = y /\ w = x ) -> ( <. v , w >. = <. x , y >. <-> <. y , x >. = <. x , y >. ) ) | 
						
							| 37 | 35 36 | imbi12d |  |-  ( ( v = y /\ w = x ) -> ( ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) <-> ( E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) -> <. y , x >. = <. x , y >. ) ) ) | 
						
							| 38 | 37 | rspc2gv |  |-  ( ( y e. X /\ x e. X ) -> ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> ( E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) -> <. y , x >. = <. x , y >. ) ) ) | 
						
							| 39 | 38 | ancoms |  |-  ( ( x e. X /\ y e. X ) -> ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> ( E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) -> <. y , x >. = <. x , y >. ) ) ) | 
						
							| 40 | 39 | adantl |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> ( E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) -> <. y , x >. = <. x , y >. ) ) ) | 
						
							| 41 |  | simprr |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> y e. X ) | 
						
							| 42 | 41 | adantr |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> y e. X ) | 
						
							| 43 |  | simpl |  |-  ( ( x e. X /\ y e. X ) -> x e. X ) | 
						
							| 44 | 43 | adantl |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> x e. X ) | 
						
							| 45 | 44 | adantr |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> x e. X ) | 
						
							| 46 |  | eqidd |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> <. y , x >. = <. y , x >. ) | 
						
							| 47 |  | vex |  |-  x e. _V | 
						
							| 48 |  | vex |  |-  y e. _V | 
						
							| 49 | 47 48 | opth |  |-  ( <. x , y >. = <. a , b >. <-> ( x = a /\ y = b ) ) | 
						
							| 50 |  | sbceq1a |  |-  ( b = y -> ( ph <-> [. y / b ]. ph ) ) | 
						
							| 51 | 50 | equcoms |  |-  ( y = b -> ( ph <-> [. y / b ]. ph ) ) | 
						
							| 52 |  | sbceq1a |  |-  ( a = x -> ( [. y / b ]. ph <-> [. x / a ]. [. y / b ]. ph ) ) | 
						
							| 53 | 52 | equcoms |  |-  ( x = a -> ( [. y / b ]. ph <-> [. x / a ]. [. y / b ]. ph ) ) | 
						
							| 54 | 51 53 | sylan9bbr |  |-  ( ( x = a /\ y = b ) -> ( ph <-> [. x / a ]. [. y / b ]. ph ) ) | 
						
							| 55 |  | dfich2 |  |-  ( [ a <> b ] ph <-> A. x A. y ( [ x / a ] [ y / b ] ph <-> [ y / a ] [ x / b ] ph ) ) | 
						
							| 56 |  | 2sp |  |-  ( A. x A. y ( [ x / a ] [ y / b ] ph <-> [ y / a ] [ x / b ] ph ) -> ( [ x / a ] [ y / b ] ph <-> [ y / a ] [ x / b ] ph ) ) | 
						
							| 57 |  | sbsbc |  |-  ( [ y / b ] ph <-> [. y / b ]. ph ) | 
						
							| 58 | 57 | sbbii |  |-  ( [ x / a ] [ y / b ] ph <-> [ x / a ] [. y / b ]. ph ) | 
						
							| 59 |  | sbsbc |  |-  ( [ x / a ] [. y / b ]. ph <-> [. x / a ]. [. y / b ]. ph ) | 
						
							| 60 | 58 59 | bitri |  |-  ( [ x / a ] [ y / b ] ph <-> [. x / a ]. [. y / b ]. ph ) | 
						
							| 61 |  | sbsbc |  |-  ( [ x / b ] ph <-> [. x / b ]. ph ) | 
						
							| 62 | 61 | sbbii |  |-  ( [ y / a ] [ x / b ] ph <-> [ y / a ] [. x / b ]. ph ) | 
						
							| 63 |  | sbsbc |  |-  ( [ y / a ] [. x / b ]. ph <-> [. y / a ]. [. x / b ]. ph ) | 
						
							| 64 | 62 63 | bitri |  |-  ( [ y / a ] [ x / b ] ph <-> [. y / a ]. [. x / b ]. ph ) | 
						
							| 65 | 56 60 64 | 3bitr3g |  |-  ( A. x A. y ( [ x / a ] [ y / b ] ph <-> [ y / a ] [ x / b ] ph ) -> ( [. x / a ]. [. y / b ]. ph <-> [. y / a ]. [. x / b ]. ph ) ) | 
						
							| 66 | 55 65 | sylbi |  |-  ( [ a <> b ] ph -> ( [. x / a ]. [. y / b ]. ph <-> [. y / a ]. [. x / b ]. ph ) ) | 
						
							| 67 | 66 | biimpd |  |-  ( [ a <> b ] ph -> ( [. x / a ]. [. y / b ]. ph -> [. y / a ]. [. x / b ]. ph ) ) | 
						
							| 68 | 67 | adantr |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> ( [. x / a ]. [. y / b ]. ph -> [. y / a ]. [. x / b ]. ph ) ) | 
						
							| 69 | 68 | com12 |  |-  ( [. x / a ]. [. y / b ]. ph -> ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> [. y / a ]. [. x / b ]. ph ) ) | 
						
							| 70 | 54 69 | biimtrdi |  |-  ( ( x = a /\ y = b ) -> ( ph -> ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> [. y / a ]. [. x / b ]. ph ) ) ) | 
						
							| 71 | 49 70 | sylbi |  |-  ( <. x , y >. = <. a , b >. -> ( ph -> ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> [. y / a ]. [. x / b ]. ph ) ) ) | 
						
							| 72 | 71 | imp |  |-  ( ( <. x , y >. = <. a , b >. /\ ph ) -> ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> [. y / a ]. [. x / b ]. ph ) ) | 
						
							| 73 | 72 | impcom |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> [. y / a ]. [. x / b ]. ph ) | 
						
							| 74 |  | sbccom |  |-  ( [. x / b ]. [. y / a ]. ph <-> [. y / a ]. [. x / b ]. ph ) | 
						
							| 75 | 73 74 | sylibr |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> [. x / b ]. [. y / a ]. ph ) | 
						
							| 76 | 46 75 | jca |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> ( <. y , x >. = <. y , x >. /\ [. x / b ]. [. y / a ]. ph ) ) | 
						
							| 77 |  | nfcv |  |-  F/_ b x | 
						
							| 78 |  | nfv |  |-  F/ b <. y , x >. = <. y , x >. | 
						
							| 79 |  | nfsbc1v |  |-  F/ b [. x / b ]. [. y / a ]. ph | 
						
							| 80 | 78 79 | nfan |  |-  F/ b ( <. y , x >. = <. y , x >. /\ [. x / b ]. [. y / a ]. ph ) | 
						
							| 81 |  | opeq2 |  |-  ( b = x -> <. y , b >. = <. y , x >. ) | 
						
							| 82 | 81 | eqeq2d |  |-  ( b = x -> ( <. y , x >. = <. y , b >. <-> <. y , x >. = <. y , x >. ) ) | 
						
							| 83 |  | sbceq1a |  |-  ( b = x -> ( [. y / a ]. ph <-> [. x / b ]. [. y / a ]. ph ) ) | 
						
							| 84 | 82 83 | anbi12d |  |-  ( b = x -> ( ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) <-> ( <. y , x >. = <. y , x >. /\ [. x / b ]. [. y / a ]. ph ) ) ) | 
						
							| 85 | 77 80 84 | spcegf |  |-  ( x e. X -> ( ( <. y , x >. = <. y , x >. /\ [. x / b ]. [. y / a ]. ph ) -> E. b ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) ) ) | 
						
							| 86 | 45 76 85 | sylc |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> E. b ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) ) | 
						
							| 87 |  | nfcv |  |-  F/_ a y | 
						
							| 88 |  | nfv |  |-  F/ a <. y , x >. = <. y , b >. | 
						
							| 89 |  | nfsbc1v |  |-  F/ a [. y / a ]. ph | 
						
							| 90 | 88 89 | nfan |  |-  F/ a ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) | 
						
							| 91 | 90 | nfex |  |-  F/ a E. b ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) | 
						
							| 92 |  | opeq1 |  |-  ( a = y -> <. a , b >. = <. y , b >. ) | 
						
							| 93 | 92 | eqeq2d |  |-  ( a = y -> ( <. y , x >. = <. a , b >. <-> <. y , x >. = <. y , b >. ) ) | 
						
							| 94 |  | sbceq1a |  |-  ( a = y -> ( ph <-> [. y / a ]. ph ) ) | 
						
							| 95 | 93 94 | anbi12d |  |-  ( a = y -> ( ( <. y , x >. = <. a , b >. /\ ph ) <-> ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) ) ) | 
						
							| 96 | 95 | exbidv |  |-  ( a = y -> ( E. b ( <. y , x >. = <. a , b >. /\ ph ) <-> E. b ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) ) ) | 
						
							| 97 | 87 91 96 | spcegf |  |-  ( y e. X -> ( E. b ( <. y , x >. = <. y , b >. /\ [. y / a ]. ph ) -> E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) ) ) | 
						
							| 98 | 42 86 97 | sylc |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) ) | 
						
							| 99 |  | simpl |  |-  ( ( y = x /\ ( x = a /\ y = b ) ) -> y = x ) | 
						
							| 100 |  | simprr |  |-  ( ( y = x /\ ( x = a /\ y = b ) ) -> y = b ) | 
						
							| 101 |  | simpl |  |-  ( ( x = a /\ y = b ) -> x = a ) | 
						
							| 102 | 101 | adantl |  |-  ( ( y = x /\ ( x = a /\ y = b ) ) -> x = a ) | 
						
							| 103 | 99 100 102 | 3eqtr3rd |  |-  ( ( y = x /\ ( x = a /\ y = b ) ) -> a = b ) | 
						
							| 104 | 103 | anim1i |  |-  ( ( ( y = x /\ ( x = a /\ y = b ) ) /\ ph ) -> ( a = b /\ ph ) ) | 
						
							| 105 | 104 | exp31 |  |-  ( y = x -> ( ( x = a /\ y = b ) -> ( ph -> ( a = b /\ ph ) ) ) ) | 
						
							| 106 | 49 105 | biimtrid |  |-  ( y = x -> ( <. x , y >. = <. a , b >. -> ( ph -> ( a = b /\ ph ) ) ) ) | 
						
							| 107 | 106 | impd |  |-  ( y = x -> ( ( <. x , y >. = <. a , b >. /\ ph ) -> ( a = b /\ ph ) ) ) | 
						
							| 108 | 48 47 | opth1 |  |-  ( <. y , x >. = <. x , y >. -> y = x ) | 
						
							| 109 | 107 108 | syl11 |  |-  ( ( <. x , y >. = <. a , b >. /\ ph ) -> ( <. y , x >. = <. x , y >. -> ( a = b /\ ph ) ) ) | 
						
							| 110 | 109 | adantl |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> ( <. y , x >. = <. x , y >. -> ( a = b /\ ph ) ) ) | 
						
							| 111 | 110 | imp |  |-  ( ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) /\ <. y , x >. = <. x , y >. ) -> ( a = b /\ ph ) ) | 
						
							| 112 | 111 | 19.8ad |  |-  ( ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) /\ <. y , x >. = <. x , y >. ) -> E. b ( a = b /\ ph ) ) | 
						
							| 113 | 112 | 19.8ad |  |-  ( ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) /\ <. y , x >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) | 
						
							| 114 | 113 | ex |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> ( <. y , x >. = <. x , y >. -> E. a E. b ( a = b /\ ph ) ) ) | 
						
							| 115 | 98 114 | embantd |  |-  ( ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) /\ ( <. x , y >. = <. a , b >. /\ ph ) ) -> ( ( E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) -> <. y , x >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) ) | 
						
							| 116 | 115 | ex |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> ( ( <. x , y >. = <. a , b >. /\ ph ) -> ( ( E. a E. b ( <. y , x >. = <. a , b >. /\ ph ) -> <. y , x >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) ) ) | 
						
							| 117 | 40 116 | syl5d |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> ( ( <. x , y >. = <. a , b >. /\ ph ) -> ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) ) ) | 
						
							| 118 | 21 31 117 | exlimd |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> ( E. b ( <. x , y >. = <. a , b >. /\ ph ) -> ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) ) ) | 
						
							| 119 | 10 18 118 | exlimd |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> ( E. a E. b ( <. x , y >. = <. a , b >. /\ ph ) -> ( A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) -> E. a E. b ( a = b /\ ph ) ) ) ) | 
						
							| 120 | 119 | impd |  |-  ( ( [ a <> b ] ph /\ ( x e. X /\ y e. X ) ) -> ( ( E. a E. b ( <. x , y >. = <. a , b >. /\ ph ) /\ A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) ) -> E. a E. b ( a = b /\ ph ) ) ) | 
						
							| 121 | 120 | rexlimdvva |  |-  ( [ a <> b ] ph -> ( E. x e. X E. y e. X ( E. a E. b ( <. x , y >. = <. a , b >. /\ ph ) /\ A. v e. X A. w e. X ( E. a E. b ( <. v , w >. = <. a , b >. /\ ph ) -> <. v , w >. = <. x , y >. ) ) -> E. a E. b ( a = b /\ ph ) ) ) | 
						
							| 122 | 7 121 | biimtrid |  |-  ( [ a <> b ] ph -> ( E! p e. ( X X. X ) E. a E. b ( p = <. a , b >. /\ ph ) -> E. a E. b ( a = b /\ ph ) ) ) |