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Metamath Proof Explorer

Theorem truimfal

Description: A -> identity. (Contributed by Anthony Hart, 22-Oct-2010) (Proof shortened by Andrew Salmon, 13-May-2011)

		Ref	Expression
	Assertion	truimfal	$⊢ (⊤ \to ⊥) \leftrightarrow ⊥$

Step	Hyp	Ref	Expression
1		trut	$⊢ ⊥ \leftrightarrow (⊤ \to ⊥)$
2	1	bicomi	$⊢ (⊤ \to ⊥) \leftrightarrow ⊥$