Metamath Proof Explorer
		
		
		
		Description:  Second property of three of the provability predicate.  (Contributed by BJ, 3-Apr-2019)
		
			
				
					|  |  | Ref | Expression | 
				
					|  | Assertion | ax-prv2 | ⊢  ( Prv  ( 𝜑  →  𝜓 )  →  ( Prv  𝜑  →  Prv  𝜓 ) ) | 
			
		
		
			
				Detailed syntax breakdown
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 0 |  | wph | ⊢ 𝜑 | 
						
							| 1 |  | wps | ⊢ 𝜓 | 
						
							| 2 | 0 1 | wi | ⊢ ( 𝜑  →  𝜓 ) | 
						
							| 3 | 2 | cprvb | ⊢ Prv  ( 𝜑  →  𝜓 ) | 
						
							| 4 | 0 | cprvb | ⊢ Prv  𝜑 | 
						
							| 5 | 1 | cprvb | ⊢ Prv  𝜓 | 
						
							| 6 | 4 5 | wi | ⊢ ( Prv  𝜑  →  Prv  𝜓 ) | 
						
							| 7 | 3 6 | wi | ⊢ ( Prv  ( 𝜑  →  𝜓 )  →  ( Prv  𝜑  →  Prv  𝜓 ) ) |