| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							bnj1286.1 | 
							 |-  B = { d | ( d C_ A /\ A. x e. d _pred ( x , A , R ) C_ d ) } | 
						
						
							| 2 | 
							
								
							 | 
							bnj1286.2 | 
							 |-  Y = <. x , ( f |` _pred ( x , A , R ) ) >.  | 
						
						
							| 3 | 
							
								
							 | 
							bnj1286.3 | 
							 |-  C = { f | E. d e. B ( f Fn d /\ A. x e. d ( f ` x ) = ( G ` Y ) ) } | 
						
						
							| 4 | 
							
								
							 | 
							bnj1286.4 | 
							 |-  D = ( dom g i^i dom h )  | 
						
						
							| 5 | 
							
								
							 | 
							bnj1286.5 | 
							 |-  E = { x e. D | ( g ` x ) =/= ( h ` x ) } | 
						
						
							| 6 | 
							
								
							 | 
							bnj1286.6 | 
							 |-  ( ph <-> ( R _FrSe A /\ g e. C /\ h e. C /\ ( g |` D ) =/= ( h |` D ) ) )  | 
						
						
							| 7 | 
							
								
							 | 
							bnj1286.7 | 
							 |-  ( ps <-> ( ph /\ x e. E /\ A. y e. E -. y R x ) )  | 
						
						
							| 8 | 
							
								1 2 3 4 5 6 7
							 | 
							bnj1256 | 
							 |-  ( ph -> E. d e. B g Fn d )  | 
						
						
							| 9 | 
							
								8
							 | 
							bnj1196 | 
							 |-  ( ph -> E. d ( d e. B /\ g Fn d ) )  | 
						
						
							| 10 | 
							
								1
							 | 
							bnj1517 | 
							 |-  ( d e. B -> A. x e. d _pred ( x , A , R ) C_ d )  | 
						
						
							| 11 | 
							
								10
							 | 
							adantr | 
							 |-  ( ( d e. B /\ g Fn d ) -> A. x e. d _pred ( x , A , R ) C_ d )  | 
						
						
							| 12 | 
							
								
							 | 
							fndm | 
							 |-  ( g Fn d -> dom g = d )  | 
						
						
							| 13 | 
							
								
							 | 
							sseq2 | 
							 |-  ( dom g = d -> ( _pred ( x , A , R ) C_ dom g <-> _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 14 | 
							
								13
							 | 
							raleqbi1dv | 
							 |-  ( dom g = d -> ( A. x e. dom g _pred ( x , A , R ) C_ dom g <-> A. x e. d _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 15 | 
							
								12 14
							 | 
							syl | 
							 |-  ( g Fn d -> ( A. x e. dom g _pred ( x , A , R ) C_ dom g <-> A. x e. d _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 16 | 
							
								15
							 | 
							adantl | 
							 |-  ( ( d e. B /\ g Fn d ) -> ( A. x e. dom g _pred ( x , A , R ) C_ dom g <-> A. x e. d _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 17 | 
							
								11 16
							 | 
							mpbird | 
							 |-  ( ( d e. B /\ g Fn d ) -> A. x e. dom g _pred ( x , A , R ) C_ dom g )  | 
						
						
							| 18 | 
							
								9 17
							 | 
							bnj593 | 
							 |-  ( ph -> E. d A. x e. dom g _pred ( x , A , R ) C_ dom g )  | 
						
						
							| 19 | 
							
								18
							 | 
							bnj937 | 
							 |-  ( ph -> A. x e. dom g _pred ( x , A , R ) C_ dom g )  | 
						
						
							| 20 | 
							
								7 19
							 | 
							bnj835 | 
							 |-  ( ps -> A. x e. dom g _pred ( x , A , R ) C_ dom g )  | 
						
						
							| 21 | 
							
								5
							 | 
							ssrab3 | 
							 |-  E C_ D  | 
						
						
							| 22 | 
							
								4
							 | 
							bnj1292 | 
							 |-  D C_ dom g  | 
						
						
							| 23 | 
							
								21 22
							 | 
							sstri | 
							 |-  E C_ dom g  | 
						
						
							| 24 | 
							
								23
							 | 
							sseli | 
							 |-  ( x e. E -> x e. dom g )  | 
						
						
							| 25 | 
							
								7 24
							 | 
							bnj836 | 
							 |-  ( ps -> x e. dom g )  | 
						
						
							| 26 | 
							
								20 25
							 | 
							bnj1294 | 
							 |-  ( ps -> _pred ( x , A , R ) C_ dom g )  | 
						
						
							| 27 | 
							
								1 2 3 4 5 6 7
							 | 
							bnj1259 | 
							 |-  ( ph -> E. d e. B h Fn d )  | 
						
						
							| 28 | 
							
								27
							 | 
							bnj1196 | 
							 |-  ( ph -> E. d ( d e. B /\ h Fn d ) )  | 
						
						
							| 29 | 
							
								10
							 | 
							adantr | 
							 |-  ( ( d e. B /\ h Fn d ) -> A. x e. d _pred ( x , A , R ) C_ d )  | 
						
						
							| 30 | 
							
								
							 | 
							fndm | 
							 |-  ( h Fn d -> dom h = d )  | 
						
						
							| 31 | 
							
								
							 | 
							sseq2 | 
							 |-  ( dom h = d -> ( _pred ( x , A , R ) C_ dom h <-> _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 32 | 
							
								31
							 | 
							raleqbi1dv | 
							 |-  ( dom h = d -> ( A. x e. dom h _pred ( x , A , R ) C_ dom h <-> A. x e. d _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 33 | 
							
								30 32
							 | 
							syl | 
							 |-  ( h Fn d -> ( A. x e. dom h _pred ( x , A , R ) C_ dom h <-> A. x e. d _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 34 | 
							
								33
							 | 
							adantl | 
							 |-  ( ( d e. B /\ h Fn d ) -> ( A. x e. dom h _pred ( x , A , R ) C_ dom h <-> A. x e. d _pred ( x , A , R ) C_ d ) )  | 
						
						
							| 35 | 
							
								29 34
							 | 
							mpbird | 
							 |-  ( ( d e. B /\ h Fn d ) -> A. x e. dom h _pred ( x , A , R ) C_ dom h )  | 
						
						
							| 36 | 
							
								28 35
							 | 
							bnj593 | 
							 |-  ( ph -> E. d A. x e. dom h _pred ( x , A , R ) C_ dom h )  | 
						
						
							| 37 | 
							
								36
							 | 
							bnj937 | 
							 |-  ( ph -> A. x e. dom h _pred ( x , A , R ) C_ dom h )  | 
						
						
							| 38 | 
							
								7 37
							 | 
							bnj835 | 
							 |-  ( ps -> A. x e. dom h _pred ( x , A , R ) C_ dom h )  | 
						
						
							| 39 | 
							
								4
							 | 
							bnj1293 | 
							 |-  D C_ dom h  | 
						
						
							| 40 | 
							
								21 39
							 | 
							sstri | 
							 |-  E C_ dom h  | 
						
						
							| 41 | 
							
								40
							 | 
							sseli | 
							 |-  ( x e. E -> x e. dom h )  | 
						
						
							| 42 | 
							
								7 41
							 | 
							bnj836 | 
							 |-  ( ps -> x e. dom h )  | 
						
						
							| 43 | 
							
								38 42
							 | 
							bnj1294 | 
							 |-  ( ps -> _pred ( x , A , R ) C_ dom h )  | 
						
						
							| 44 | 
							
								26 43
							 | 
							ssind | 
							 |-  ( ps -> _pred ( x , A , R ) C_ ( dom g i^i dom h ) )  | 
						
						
							| 45 | 
							
								44 4
							 | 
							sseqtrrdi | 
							 |-  ( ps -> _pred ( x , A , R ) C_ D )  |