| Step | Hyp | Ref | Expression | 
						
							| 1 |  | pi1xfr.p |  |-  P = ( J pi1 ( F ` 0 ) ) | 
						
							| 2 |  | pi1xfr.q |  |-  Q = ( J pi1 ( F ` 1 ) ) | 
						
							| 3 |  | pi1xfr.b |  |-  B = ( Base ` P ) | 
						
							| 4 |  | pi1xfr.g |  |-  G = ran ( g e. U. B |-> <. [ g ] ( ~=ph ` J ) , [ ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ] ( ~=ph ` J ) >. ) | 
						
							| 5 |  | pi1xfr.j |  |-  ( ph -> J e. ( TopOn ` X ) ) | 
						
							| 6 |  | pi1xfr.f |  |-  ( ph -> F e. ( II Cn J ) ) | 
						
							| 7 |  | pi1xfrval.i |  |-  ( ph -> I e. ( II Cn J ) ) | 
						
							| 8 |  | pi1xfrval.1 |  |-  ( ph -> ( F ` 1 ) = ( I ` 0 ) ) | 
						
							| 9 |  | pi1xfrval.2 |  |-  ( ph -> ( I ` 1 ) = ( F ` 0 ) ) | 
						
							| 10 | 5 | adantr |  |-  ( ( ph /\ g e. U. B ) -> J e. ( TopOn ` X ) ) | 
						
							| 11 |  | iitopon |  |-  II e. ( TopOn ` ( 0 [,] 1 ) ) | 
						
							| 12 |  | cnf2 |  |-  ( ( II e. ( TopOn ` ( 0 [,] 1 ) ) /\ J e. ( TopOn ` X ) /\ F e. ( II Cn J ) ) -> F : ( 0 [,] 1 ) --> X ) | 
						
							| 13 | 11 5 6 12 | mp3an2i |  |-  ( ph -> F : ( 0 [,] 1 ) --> X ) | 
						
							| 14 |  | 0elunit |  |-  0 e. ( 0 [,] 1 ) | 
						
							| 15 |  | ffvelcdm |  |-  ( ( F : ( 0 [,] 1 ) --> X /\ 0 e. ( 0 [,] 1 ) ) -> ( F ` 0 ) e. X ) | 
						
							| 16 | 13 14 15 | sylancl |  |-  ( ph -> ( F ` 0 ) e. X ) | 
						
							| 17 | 16 | adantr |  |-  ( ( ph /\ g e. U. B ) -> ( F ` 0 ) e. X ) | 
						
							| 18 | 3 | a1i |  |-  ( ph -> B = ( Base ` P ) ) | 
						
							| 19 | 1 5 16 18 | pi1eluni |  |-  ( ph -> ( g e. U. B <-> ( g e. ( II Cn J ) /\ ( g ` 0 ) = ( F ` 0 ) /\ ( g ` 1 ) = ( F ` 0 ) ) ) ) | 
						
							| 20 | 19 | biimpa |  |-  ( ( ph /\ g e. U. B ) -> ( g e. ( II Cn J ) /\ ( g ` 0 ) = ( F ` 0 ) /\ ( g ` 1 ) = ( F ` 0 ) ) ) | 
						
							| 21 | 20 | simp1d |  |-  ( ( ph /\ g e. U. B ) -> g e. ( II Cn J ) ) | 
						
							| 22 | 20 | simp2d |  |-  ( ( ph /\ g e. U. B ) -> ( g ` 0 ) = ( F ` 0 ) ) | 
						
							| 23 | 20 | simp3d |  |-  ( ( ph /\ g e. U. B ) -> ( g ` 1 ) = ( F ` 0 ) ) | 
						
							| 24 | 1 3 10 17 21 22 23 | elpi1i |  |-  ( ( ph /\ g e. U. B ) -> [ g ] ( ~=ph ` J ) e. B ) | 
						
							| 25 |  | eqid |  |-  ( Base ` Q ) = ( Base ` Q ) | 
						
							| 26 |  | 1elunit |  |-  1 e. ( 0 [,] 1 ) | 
						
							| 27 |  | ffvelcdm |  |-  ( ( F : ( 0 [,] 1 ) --> X /\ 1 e. ( 0 [,] 1 ) ) -> ( F ` 1 ) e. X ) | 
						
							| 28 | 13 26 27 | sylancl |  |-  ( ph -> ( F ` 1 ) e. X ) | 
						
							| 29 | 28 | adantr |  |-  ( ( ph /\ g e. U. B ) -> ( F ` 1 ) e. X ) | 
						
							| 30 | 7 | adantr |  |-  ( ( ph /\ g e. U. B ) -> I e. ( II Cn J ) ) | 
						
							| 31 | 6 | adantr |  |-  ( ( ph /\ g e. U. B ) -> F e. ( II Cn J ) ) | 
						
							| 32 | 21 31 23 | pcocn |  |-  ( ( ph /\ g e. U. B ) -> ( g ( *p ` J ) F ) e. ( II Cn J ) ) | 
						
							| 33 | 21 31 | pco0 |  |-  ( ( ph /\ g e. U. B ) -> ( ( g ( *p ` J ) F ) ` 0 ) = ( g ` 0 ) ) | 
						
							| 34 | 9 | adantr |  |-  ( ( ph /\ g e. U. B ) -> ( I ` 1 ) = ( F ` 0 ) ) | 
						
							| 35 | 22 33 34 | 3eqtr4rd |  |-  ( ( ph /\ g e. U. B ) -> ( I ` 1 ) = ( ( g ( *p ` J ) F ) ` 0 ) ) | 
						
							| 36 | 30 32 35 | pcocn |  |-  ( ( ph /\ g e. U. B ) -> ( I ( *p ` J ) ( g ( *p ` J ) F ) ) e. ( II Cn J ) ) | 
						
							| 37 | 30 32 | pco0 |  |-  ( ( ph /\ g e. U. B ) -> ( ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ` 0 ) = ( I ` 0 ) ) | 
						
							| 38 | 8 | adantr |  |-  ( ( ph /\ g e. U. B ) -> ( F ` 1 ) = ( I ` 0 ) ) | 
						
							| 39 | 37 38 | eqtr4d |  |-  ( ( ph /\ g e. U. B ) -> ( ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ` 0 ) = ( F ` 1 ) ) | 
						
							| 40 | 30 32 | pco1 |  |-  ( ( ph /\ g e. U. B ) -> ( ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ` 1 ) = ( ( g ( *p ` J ) F ) ` 1 ) ) | 
						
							| 41 | 21 31 | pco1 |  |-  ( ( ph /\ g e. U. B ) -> ( ( g ( *p ` J ) F ) ` 1 ) = ( F ` 1 ) ) | 
						
							| 42 | 40 41 | eqtrd |  |-  ( ( ph /\ g e. U. B ) -> ( ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ` 1 ) = ( F ` 1 ) ) | 
						
							| 43 | 2 25 10 29 36 39 42 | elpi1i |  |-  ( ( ph /\ g e. U. B ) -> [ ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ] ( ~=ph ` J ) e. ( Base ` Q ) ) | 
						
							| 44 |  | eceq1 |  |-  ( g = h -> [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) | 
						
							| 45 |  | oveq1 |  |-  ( g = h -> ( g ( *p ` J ) F ) = ( h ( *p ` J ) F ) ) | 
						
							| 46 | 45 | oveq2d |  |-  ( g = h -> ( I ( *p ` J ) ( g ( *p ` J ) F ) ) = ( I ( *p ` J ) ( h ( *p ` J ) F ) ) ) | 
						
							| 47 | 46 | eceq1d |  |-  ( g = h -> [ ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ] ( ~=ph ` J ) = [ ( I ( *p ` J ) ( h ( *p ` J ) F ) ) ] ( ~=ph ` J ) ) | 
						
							| 48 |  | phtpcer |  |-  ( ~=ph ` J ) Er ( II Cn J ) | 
						
							| 49 | 48 | a1i |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( ~=ph ` J ) Er ( II Cn J ) ) | 
						
							| 50 | 22 | 3ad2antr1 |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( g ` 0 ) = ( F ` 0 ) ) | 
						
							| 51 | 21 | 3ad2antr1 |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> g e. ( II Cn J ) ) | 
						
							| 52 | 6 | adantr |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> F e. ( II Cn J ) ) | 
						
							| 53 | 51 52 | pco0 |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( ( g ( *p ` J ) F ) ` 0 ) = ( g ` 0 ) ) | 
						
							| 54 | 9 | adantr |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( I ` 1 ) = ( F ` 0 ) ) | 
						
							| 55 | 50 53 54 | 3eqtr4rd |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( I ` 1 ) = ( ( g ( *p ` J ) F ) ` 0 ) ) | 
						
							| 56 | 7 | adantr |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> I e. ( II Cn J ) ) | 
						
							| 57 | 49 56 | erref |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> I ( ~=ph ` J ) I ) | 
						
							| 58 | 23 | 3ad2antr1 |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( g ` 1 ) = ( F ` 0 ) ) | 
						
							| 59 |  | simpr3 |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) | 
						
							| 60 | 49 51 | erth |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( g ( ~=ph ` J ) h <-> [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) | 
						
							| 61 | 59 60 | mpbird |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> g ( ~=ph ` J ) h ) | 
						
							| 62 | 49 52 | erref |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> F ( ~=ph ` J ) F ) | 
						
							| 63 | 58 61 62 | pcohtpy |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( g ( *p ` J ) F ) ( ~=ph ` J ) ( h ( *p ` J ) F ) ) | 
						
							| 64 | 55 57 63 | pcohtpy |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ( ~=ph ` J ) ( I ( *p ` J ) ( h ( *p ` J ) F ) ) ) | 
						
							| 65 | 49 64 | erthi |  |-  ( ( ph /\ ( g e. U. B /\ h e. U. B /\ [ g ] ( ~=ph ` J ) = [ h ] ( ~=ph ` J ) ) ) -> [ ( I ( *p ` J ) ( g ( *p ` J ) F ) ) ] ( ~=ph ` J ) = [ ( I ( *p ` J ) ( h ( *p ` J ) F ) ) ] ( ~=ph ` J ) ) | 
						
							| 66 | 4 24 43 44 47 65 | fliftfund |  |-  ( ph -> Fun G ) | 
						
							| 67 | 4 24 43 | fliftf |  |-  ( ph -> ( Fun G <-> G : ran ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) --> ( Base ` Q ) ) ) | 
						
							| 68 | 66 67 | mpbid |  |-  ( ph -> G : ran ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) --> ( Base ` Q ) ) | 
						
							| 69 | 1 5 16 18 | pi1bas2 |  |-  ( ph -> B = ( U. B /. ( ~=ph ` J ) ) ) | 
						
							| 70 |  | df-qs |  |-  ( U. B /. ( ~=ph ` J ) ) = { s | E. g e. U. B s = [ g ] ( ~=ph ` J ) } | 
						
							| 71 |  | eqid |  |-  ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) = ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) | 
						
							| 72 | 71 | rnmpt |  |-  ran ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) = { s | E. g e. U. B s = [ g ] ( ~=ph ` J ) } | 
						
							| 73 | 70 72 | eqtr4i |  |-  ( U. B /. ( ~=ph ` J ) ) = ran ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) | 
						
							| 74 | 69 73 | eqtrdi |  |-  ( ph -> B = ran ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) ) | 
						
							| 75 | 74 | feq2d |  |-  ( ph -> ( G : B --> ( Base ` Q ) <-> G : ran ( g e. U. B |-> [ g ] ( ~=ph ` J ) ) --> ( Base ` Q ) ) ) | 
						
							| 76 | 68 75 | mpbird |  |-  ( ph -> G : B --> ( Base ` Q ) ) |