| Step | Hyp | Ref | Expression | 
						
							| 1 |  | simp1 |  |-  ( ( ps /\ ph /\ ch ) -> ps ) | 
						
							| 2 | 1 | a1i |  |-  ( ( ph -> A. x ph ) -> ( ( ps /\ ph /\ ch ) -> ps ) ) | 
						
							| 3 |  | ax-5 |  |-  ( ps -> A. x ps ) | 
						
							| 4 | 2 3 | syl6 |  |-  ( ( ph -> A. x ph ) -> ( ( ps /\ ph /\ ch ) -> A. x ps ) ) | 
						
							| 5 |  | simp2 |  |-  ( ( ps /\ ph /\ ch ) -> ph ) | 
						
							| 6 | 5 | imim1i |  |-  ( ( ph -> A. x ph ) -> ( ( ps /\ ph /\ ch ) -> A. x ph ) ) | 
						
							| 7 |  | simp3 |  |-  ( ( ps /\ ph /\ ch ) -> ch ) | 
						
							| 8 | 7 | a1i |  |-  ( ( ph -> A. x ph ) -> ( ( ps /\ ph /\ ch ) -> ch ) ) | 
						
							| 9 |  | ax-5 |  |-  ( ch -> A. x ch ) | 
						
							| 10 | 8 9 | syl6 |  |-  ( ( ph -> A. x ph ) -> ( ( ps /\ ph /\ ch ) -> A. x ch ) ) | 
						
							| 11 | 4 6 10 | 3jcad |  |-  ( ( ph -> A. x ph ) -> ( ( ps /\ ph /\ ch ) -> ( A. x ps /\ A. x ph /\ A. x ch ) ) ) | 
						
							| 12 |  | 19.26-3an |  |-  ( A. x ( ps /\ ph /\ ch ) <-> ( A. x ps /\ A. x ph /\ A. x ch ) ) | 
						
							| 13 | 11 12 | imbitrrdi |  |-  ( ( ph -> A. x ph ) -> ( ( ps /\ ph /\ ch ) -> A. x ( ps /\ ph /\ ch ) ) ) |