forewarned is forearmed
Knowledge in advance enables one to be prepared, as in Let me know when he's in town so I can take the phone off the hookforewarned is forearmed. This expression originated as a Latin proverb, Praemonitus, praemunitus, which was translated into English by the early 1500s. It soon was put to broader use than its original military applications.
Dictionary.com presents 366 FAQs, incorporating some of the frequently asked questions from the past with newer queries.