Database CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY Other axiomatizations related to classical propositional calculus Derive the Lukasiewicz axioms from Nicod's axiom nic-imp  
				
		 
		
			
		 
		Description:   Inference for nic-mp  using nic-ax  as major premise.  (Contributed by Jeff Hoffman , 17-Nov-2007)   (Proof modification is discouraged.) 
       (New usage is discouraged.) 
		
			
				
					Ref 
					Expression 
				 
					
						Hypothesis 
						nic-imp.1 ⊢  ( 𝜑   ⊼  ( 𝜒   ⊼  𝜓  ) )  
				
					Assertion 
					nic-imp ⊢   ( ( 𝜃   ⊼  𝜒  )  ⊼  ( ( 𝜑   ⊼  𝜃  )  ⊼  ( 𝜑   ⊼  𝜃  ) ) )  
			
		 
		
				Proof 
				
					
						Step 
						Hyp 
						Ref 
						Expression 
					 
						
							1 
								
							 
							nic-imp.1 ⊢  ( 𝜑   ⊼  ( 𝜒   ⊼  𝜓  ) )  
						
							2 
								
							 
							nic-ax ⊢  ( ( 𝜑   ⊼  ( 𝜒   ⊼  𝜓  ) )  ⊼  ( ( 𝜏   ⊼  ( 𝜏   ⊼  𝜏  ) )  ⊼  ( ( 𝜃   ⊼  𝜒  )  ⊼  ( ( 𝜑   ⊼  𝜃  )  ⊼  ( 𝜑   ⊼  𝜃  ) ) ) ) )  
						
							3 
								1  2 
							 
							nic-mp ⊢  ( ( 𝜃   ⊼  𝜒  )  ⊼  ( ( 𝜑   ⊼  𝜃  )  ⊼  ( 𝜑   ⊼  𝜃  ) ) )