If logic discloses the heart of language, then grammar supplies the body. According to Lily's Grammar, otherwise known as The Royal Grammar and the predominant textbook in England throughout the seventeenth century, the discipline teaches ‘the art of writing and speaking rightly’. As the mainstay of early-modern education, it inculcates the quintessentially human skill that distinguishes men from beasts, enabling them to flourish in society. In his influential Minerva, sive De causis Latinae linguae (1587), Franciscus Sanctius explains that grammar, ‘the art of speaking rightly’, is the most basic of the three arts of language. Obadiah Walker's Of Education (1673) reiterates its propaedeutic role. Neither rhetoric nor logic, that teach one, respectively, to speak ‘perspicuously, decently, and persuasively’, and ‘pertinently and rationally’, are to be learned before the linguistic rudiments enshrined in grammar. Bacon records the essential, if unglamorous, nature of the discipline; it is ‘the harbinger of other sciences; an office not indeed very noble, yet very necessary’. In his Philosophia rationalis (1638) Thomas Campanella calls it ‘an instrumental art’. Pupils were expected to have mastered it at grammar school, and its preliminary status is reflected in the fact that the subject did not officially appear in the curricula of the Universities of either Oxford or Cambridge. Unofficially, however, undergraduates were encouraged to refresh their memories; Holdsworth urgently declares that ‘grammers must not be forgotten’. The art was indispensable in a world where a gentleman's status was partly measured by his linguistic virtuosity.