Theorem pm3.22 252

Description: Theorem *3.22 of [WhiteheadRussell] p. 111. (Contributed by NM, 3-Jan-2005.) (Proof shortened by Wolf Lammen, 13-Nov-2012.)

Assertion

Ref	Expression
pm3.22	⊢ ((𝜑 ∧ 𝜓) → (𝜓 ∧ 𝜑))

Proof of Theorem pm3.22

Step	Hyp	Ref	Expression
1		pm3.21 251	. 2 ⊢ (𝜑 → (𝜓 → (𝜓 ∧ 𝜑)))
2	1	imp 115	1 ⊢ ((𝜑 ∧ 𝜓) → (𝜓 ∧ 𝜑))

Syntax hints:   → wi 4   ∧ wa 97

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101

This theorem is referenced by:  ancom  253  ancom2s  500  ancom1s  503  eupickb  1981  enq0sym  6530  bj-peano4  10080