Metamath Proof Explorer


Theorem e002

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

Ref Expression
Hypotheses e002.1 ⊢ φ
e002.2 ⊢ ψ
e002.3 ⊢ χ , θ → τ
e002.4 ⊢ φ → ψ → τ → η
Assertion e002 ⊢ χ , θ → η

Proof

Step Hyp Ref Expression
1 e002.1 ⊢ φ
2 e002.2 ⊢ ψ
3 e002.3 ⊢ χ , θ → τ
4 e002.4 ⊢ φ → ψ → τ → η
5 1 vd02 ⊢ χ , θ → φ
6 2 vd02 ⊢ χ , θ → ψ
7 5 6 3 4 e222 ⊢ χ , θ → η