paren fix from domfarolino. closes #23.
paren fix from domfarolino. closes #23.

avigad/logic_and_proof,avigad/logic_and_proof,leanprover/logic_and_proof,rlewis1988/logic_and_proof,leanprover/logic_and_proof,rlewis1988/logic_and_proof,avigad/logic_and_proof,rlewis1988/logic_and_proof,leanprover/logic_and_proof