Theorem pm2.24ii

Description: A contradiction implies anything. Inference associated with pm2.21i and pm2.24i . (Contributed by NM, 27-Feb-2008)

	Ref	Expression
Hypotheses	pm2.24ii.1	$$⊢\phi$$
	pm2.24ii.2	$$⊢\neg \phi$$
Assertion	pm2.24ii	$$⊢\psi$$

Proof

Step	Hyp	Ref	Expression
1		pm2.24ii.1	$$⊢\phi$$
2		pm2.24ii.2	$$⊢\neg \phi$$
3	2	pm2.21i	$$⊢\phi \to \psi$$
4	1 3	ax-mp	$$⊢\psi$$