| Step | Hyp | Ref | Expression | 
						
							| 1 |  | caovcang.1 |  |-  ( ( ph /\ ( x e. T /\ y e. S /\ z e. S ) ) -> ( ( x F y ) = ( x F z ) <-> y = z ) ) | 
						
							| 2 | 1 | ralrimivvva |  |-  ( ph -> A. x e. T A. y e. S A. z e. S ( ( x F y ) = ( x F z ) <-> y = z ) ) | 
						
							| 3 |  | oveq1 |  |-  ( x = A -> ( x F y ) = ( A F y ) ) | 
						
							| 4 |  | oveq1 |  |-  ( x = A -> ( x F z ) = ( A F z ) ) | 
						
							| 5 | 3 4 | eqeq12d |  |-  ( x = A -> ( ( x F y ) = ( x F z ) <-> ( A F y ) = ( A F z ) ) ) | 
						
							| 6 | 5 | bibi1d |  |-  ( x = A -> ( ( ( x F y ) = ( x F z ) <-> y = z ) <-> ( ( A F y ) = ( A F z ) <-> y = z ) ) ) | 
						
							| 7 |  | oveq2 |  |-  ( y = B -> ( A F y ) = ( A F B ) ) | 
						
							| 8 | 7 | eqeq1d |  |-  ( y = B -> ( ( A F y ) = ( A F z ) <-> ( A F B ) = ( A F z ) ) ) | 
						
							| 9 |  | eqeq1 |  |-  ( y = B -> ( y = z <-> B = z ) ) | 
						
							| 10 | 8 9 | bibi12d |  |-  ( y = B -> ( ( ( A F y ) = ( A F z ) <-> y = z ) <-> ( ( A F B ) = ( A F z ) <-> B = z ) ) ) | 
						
							| 11 |  | oveq2 |  |-  ( z = C -> ( A F z ) = ( A F C ) ) | 
						
							| 12 | 11 | eqeq2d |  |-  ( z = C -> ( ( A F B ) = ( A F z ) <-> ( A F B ) = ( A F C ) ) ) | 
						
							| 13 |  | eqeq2 |  |-  ( z = C -> ( B = z <-> B = C ) ) | 
						
							| 14 | 12 13 | bibi12d |  |-  ( z = C -> ( ( ( A F B ) = ( A F z ) <-> B = z ) <-> ( ( A F B ) = ( A F C ) <-> B = C ) ) ) | 
						
							| 15 | 6 10 14 | rspc3v |  |-  ( ( A e. T /\ B e. S /\ C e. S ) -> ( A. x e. T A. y e. S A. z e. S ( ( x F y ) = ( x F z ) <-> y = z ) -> ( ( A F B ) = ( A F C ) <-> B = C ) ) ) | 
						
							| 16 | 2 15 | mpan9 |  |-  ( ( ph /\ ( A e. T /\ B e. S /\ C e. S ) ) -> ( ( A F B ) = ( A F C ) <-> B = C ) ) |