Cocker's Arithmetick, also known by its full title "Cocker's Arithmetick: Being a Plain and Familiar Method Suitable to the Meanest Capacity for the Full Understanding of That Incomparable Art, As It Is Now Taught by the Ablest School-Masters in City and Country", is a grammar schoolmathematics textbook written by Edward Cocker and published posthumously by John Hawkins in 1677. Arithmetick along with companion volume, Decimal Arithmetick published in 1684, were used to teach mathematics in schools in the United Kingdom for more than 150 years. Some controversy exists over the authorship of the book. Augustus De Morgan claimed the work was written by Hawkins, who merely used Cocker's name to lend the authority of his reputation to the book. Ruth Wallis, in 1997, wrote an article in Annals of Science, claiming De Morgan's analysis was flawed and Cocker was the real author. The popularity of Arithmetick is unquestioned by its more than 130 editions, and that its place was woven in the fabric of the popular culture of the time is evidenced by its references in the phrase, "according to Cocker", meaning "absolutely correct" or "according to the rules". Such noted figures of history as Benjamin Franklin and Thomas Simpson are documented as having used the book. Over 100 years after its publication, Samuel Johnson carried a copy of Arithmetick on his tour of Scotland, and mentions it in his letters: Though popular, like most texts of its time, Arithmetickstyle is formal, stiff and difficult to follow as illustrated in its explanation of the "rule of three". As well as the rule of three, Arithmetick contains instructions on alligation and the rule of false position. Following the common practice of textbooks at the time, each rule is illustrated with numerous examples of commercial transactions involving the exchange of wheat, rye and other seeds; calculation of costs for the erection of houses and other structures; and the rotation of gears on a shaft. The text contains the earliest known use of the term lowest terms.
