Homo unius libri
Homo unius libri ('(a) man of one book') is a Latin phrase attributed to Thomas Aquinas by bishop Jeremy Taylor (1613–1667), who claimed that Aquinas is reputed to have employed the phrase "hominem unius libri timeo" ('I fear the man of a single book'). The poet Robert Southey recalled the tradition in which the quotation became embedded: When St Thomas Aquinas was asked in what manner a man might best become learned, he answered, "By reading one book"; "meaning," says Bishop Taylor, "that an understanding entertained with several objects is intent upon neither, and profits not." The homo unius libri is indeed proverbially formidable to all conversational figurantes.