Our principal published her fifty-page "Treatise on Gum Chewing" days before she was carted away by men in white coats. Treatises are formal papers that treat a specific subject. Gum chewing shouldn't merit one.
Treatise is related to the verb treat, which means "deal with." A doctor treats a patient. A teacher treats the senator's child with kid gloves. Treatise means a written paper or exposition that deals with or treats a specific subject.
