Robert Recorde - the man who invented the equals sign
Recorde was born in Tenby in the year 1510, the son of Thomas Recorde from the Pembrokeshire town itself and of Rose Jones of North Wales. He was a gifted child, receiving his early instruction in the small school that was then based in the town church.
However, when he was just fifteen years old Recorde left Tenby to make his way to Oxford where he began a course of studies in mathematics. It must have been a terrifying experience for a young man from the far west of Wales, suddenly thrust into the bustling academic life of Oxford, but he persevered, gained his degree and in 1531 was elected Fellow of All Souls.
In 1545, Recorde went to Cambridge where he studied for a degree in medicine. It was in this field that he first made his mark in the world. He became physician to the young king Edward V1 and, after his death from TB, to Queen Mary - despite his clear Protestant leanings. Recorde even dedicated some of his books to this Catholic monarch who quickly earned the accolade of Bloody Mary due to the number of Protestant martyrs she caused to be burned at the stake.
Recorde's life in public service was far from easy. As well as being a royal physician, he was, at various times, controller of the royal mint at Bristol and Comptroller of Mines and Monies in Ireland. He was, perhaps, not very skilled at public affairs as by 1553 the mines and mints in Ireland were showing a loss and were, consequently, closed down.
More importantly, he quarrelled with Sir William Herbert, later the Earl of Pembroke, and made the stupid mistake of trying to sue him for defamation of character. Pembroke counter-sued, Recorde lost and ended up being ordered to pay a fine of £1,000, an enormous sum for those days. He couldn't - or wouldn't - pay and was sent to the Kings Bench Prison in Southwark where he died in 1558.
However, it is as a mathematician that Recorde will be remembered. He wrote several seminal books, works such as The Grounde of Artes in 1540 and The Urinal of Physic in 1548. Interestingly, Recorde wrote in English, not the Latin that was usual for academic tomes at this time. He wanted everyone to be able to read his works.
His most influential work, written in the classical style of a dialogue between master and scholar, was The Whetstone of Witte. This book appeared in 1557 and is credited as being the book that first introduced algebra into Britain.
The Whetstone of Witte is also the work that used, for the first time, the equals sign. Unlike our modern version, Recorde's equals sign consisted of two long parallel lines that could, if necessary, be drawn right the way around the globe and still not join together. As he said,
"noe 2 thynges can be moare equalle."
The concept was not immediately popular but by 1700, in a shortened or abbreviated form, the equals sign had become accepted throughout the country - for working out bills, for academic study, even as a method of speech. There is a memorial to Recorde in St Mary's Church in Tenby but, other than that, most people will never have heard about this remarkable and far-sighted mathematician.
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