Metamath Proof Explorer

Theorem bnj667

Description: /\ -manipulation. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

		Ref	Expression
	Assertion	bnj667	$⊢ (φ \land ψ \land χ \land θ) \to (ψ \land χ \land θ)$

Step	Hyp	Ref	Expression
1		bnj446	$⊢ (φ \land ψ \land χ \land θ) \leftrightarrow ((ψ \land χ \land θ) \land φ)$
2	1	simplbi	$⊢ (φ \land ψ \land χ \land θ) \to (ψ \land χ \land θ)$