Metamath Proof Explorer


Theorem consym1

Description: A symmetry with /\ .

See negsym1 for more information. (Contributed by Anthony Hart, 4-Sep-2011)

Ref Expression
Assertion consym1 ⊢ ψ ∧ ψ ∧ ⊥ → ψ ∧ φ

Proof

Step Hyp Ref Expression
1 falim ⊢ ⊥ → ψ ∧ ψ ∧ ⊥ → ψ ∧ φ
2 1 ad2antll ⊢ ψ ∧ ψ ∧ ⊥ → ψ ∧ ψ ∧ ⊥ → ψ ∧ φ
3 2 pm2.43i ⊢ ψ ∧ ψ ∧ ⊥ → ψ ∧ φ