Convince, an often stated rule says, may be followed only by that or of, never by to: We convinced him that he should enter (not convinced him to enter) the contest. He was convinced of the wisdom of entering. In examples to support the rule, convince is often contrasted with persuade, which may take to, of, or that followed by the appropriate construction: We persuaded him to seek counseling (or of his need for counseling or that he should seek counseling). The history of usage does not support the rule. Convince (someone) to has been in use since the 16th century and, despite objections by some, occurs freely today in all varieties of speech and writing and is fully standard: Members of the cabinet are trying to convince the prime minister not to resign.