Theorem e011 44705

Description: A virtual deduction elimination rule. (Contributed by Alan Sare, 24-Jun-2011.) (Proof modification is discouraged.) (New usage is discouraged.)

Hypotheses

Ref	Expression
e011.1	⊢ 𝜑
e011.2	⊢ (   𝜓   ▶   𝜒   )
e011.3	⊢ (   𝜓   ▶   𝜃   )
e011.4	⊢ (𝜑 → (𝜒 → (𝜃 → 𝜏)))

Assertion

Ref	Expression
e011	⊢ (   𝜓   ▶   𝜏   )

Proof of Theorem e011

Step	Hyp	Ref	Expression
1		e011.1	. . 3 ⊢ 𝜑
2	1	vd01 44622	. 2 ⊢ (   𝜓   ▶   𝜑   )
3		e011.2	. 2 ⊢ (   𝜓   ▶   𝜒   )
4		e011.3	. 2 ⊢ (   𝜓   ▶   𝜃   )
5		e011.4	. 2 ⊢ (𝜑 → (𝜒 → (𝜃 → 𝜏)))
6	2, 3, 4, 5	e111 44699	1 ⊢ (   𝜓   ▶   𝜏   )

Syntax hints:   → wi 4  (   wvd1 44594

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem depends on definitions:  df-bi 207  df-vd1 44595

This theorem is referenced by: (None)