Metamath Proof Explorer


Theorem jcab

Description: Distributive law for implication over conjunction. Compare Theorem *4.76 of WhiteheadRussell p. 121. (Contributed by NM, 3-Apr-1994) (Proof shortened by Wolf Lammen, 27-Nov-2013)

Ref Expression
Assertion jcab φ ψ χ φ ψ φ χ

Proof

Step Hyp Ref Expression
1 simpl ψ χ ψ
2 1 imim2i φ ψ χ φ ψ
3 simpr ψ χ χ
4 3 imim2i φ ψ χ φ χ
5 2 4 jca φ ψ χ φ ψ φ χ
6 pm3.43 φ ψ φ χ φ ψ χ
7 5 6 impbii φ ψ χ φ ψ φ χ