Metamath Proof Explorer
		
		
		
		Description:  Commutation of antecedents.  Rotate left.  (Contributed by NM, 25-Apr-1994)  (Proof shortened by Mel L. O'Cat, 15-Aug-2004)
		
			
				
					 | 
					 | 
					Ref | 
					Expression | 
				
					
						 | 
						Hypothesis | 
						com4.1 | 
						⊢ ( 𝜑  →  ( 𝜓  →  ( 𝜒  →  ( 𝜃  →  𝜏 ) ) ) )  | 
					
				
					 | 
					Assertion | 
					com4l | 
					⊢  ( 𝜓  →  ( 𝜒  →  ( 𝜃  →  ( 𝜑  →  𝜏 ) ) ) )  | 
				
			
		
		
			
				Proof
				
					
						| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							com4.1 | 
							⊢ ( 𝜑  →  ( 𝜓  →  ( 𝜒  →  ( 𝜃  →  𝜏 ) ) ) )  | 
						
						
							| 2 | 
							
								1
							 | 
							com3l | 
							⊢ ( 𝜓  →  ( 𝜒  →  ( 𝜑  →  ( 𝜃  →  𝜏 ) ) ) )  | 
						
						
							| 3 | 
							
								2
							 | 
							com34 | 
							⊢ ( 𝜓  →  ( 𝜒  →  ( 𝜃  →  ( 𝜑  →  𝜏 ) ) ) )  |