Theorem com13

Description: Commutation of antecedents. Swap 1st and 3rd. (Contributed by NM, 25-Apr-1994) (Proof shortened by Wolf Lammen, 28-Jul-2012)

	Ref	Expression
Hypothesis	com3.1	$$⊢\phi \to \left(\psi \to \left(\chi \to \theta \right)\right)$$
Assertion	com13	$$⊢\chi \to \left(\psi \to \left(\phi \to \theta \right)\right)$$

Proof

Step	Hyp	Ref	Expression
1		com3.1	$$⊢\phi \to \left(\psi \to \left(\chi \to \theta \right)\right)$$
2	1	com3r	$$⊢\chi \to \left(\phi \to \left(\psi \to \theta \right)\right)$$
3	2	com23	$$⊢\chi \to \left(\psi \to \left(\phi \to \theta \right)\right)$$