William Shakespeare (1564–1616), British poet, dramatist. Celia, in As You Like It, act 1, sc. 2, l. 52-3 (1623).
Shakespeare was possibly making a punning reference to The Whetstone of Witte—a famous treatise on algebra by Robert Recorde published in 1557. The book's title was a literal translation of Cos Ingenii (cos being the Latin for "whetstone," while Coss or the Cossic Art was also the old name for algebra).