Robert Recorde

Robert Recorde was a Welsh doctor and mathematician, born around 1510 in Tenby, the second son of Thomas Recorde and Rose Jones. He is thought to have entered the University of Oxford about 1525, graduated B.A. in 1531 and was elected a Fellow of All Souls College that year, then took his M.D. at Cambridge in 1545 and practised medicine in London. He became controller of the Bristol mint in 1549 and in 1551 general surveyor of the mines and monies in Ireland. He wrote elementary mathematics textbooks in English, in a deliberate course of study open to readers without Latin or Greek: The Grounde of Artes of 1543 on arithmetic, the Pathwaie to Knowledge of 1551 on geometry, The Castle of Knowledge of 1556 on astronomy, and The Whetstone of Witte of 1557, in which he invented the equals sign. MacTutor says he virtually established the English school of mathematics and first introduced algebra into England. After losing a libel suit brought by the Earl of Pembroke he was imprisoned for debt in the King's Bench prison in Southwark and died there in 1558.