Metamath Proof Explorer

Theorem exp56

Description: An exportation inference. (Contributed by Jeff Hankins, 7-Jul-2009)

		Ref	Expression
	Hypothesis	exp56.1	$⊢ (((φ \land ψ) \land χ) \land (θ \land τ)) \to η$
	Assertion	exp56	$⊢ φ \to (ψ \to (χ \to (θ \to (τ \to η))))$

Step	Hyp	Ref	Expression
1		exp56.1	$⊢ (((φ \land ψ) \land χ) \land (θ \land τ)) \to η$
2	1	ex	$⊢ ((φ \land ψ) \land χ) \to ((θ \land τ) \to η)$
3	2	exp5d	$⊢ φ \to (ψ \to (χ \to (θ \to (τ \to η))))$