Robert Recorde () was a Welsh physician and mathematician. He invented the

equals sign The equals sign (British English) or equal sign (American English), also known as the equality sign, is the mathematical symbol , which is used to indicate equality. In an equation it is placed between two expressions that have the same valu ...

(=) and also introduced the pre-existing plus (+) and

minus The plus sign () and the minus sign () are mathematical symbols used to denote positive and negative functions, respectively. In addition, the symbol represents the operation of addition, which results in a sum, while the symbol represent ...

(−) signs to English speakers in 1557.

Biography

Born around 1510, Robert Recorde was the second and last son of Thomas and Rose Recorde of

Tenby Tenby () is a seaside town and community (Wales), community in the county of Pembrokeshire, Wales. It lies within Carmarthen Bay. Notable features include of sandy beaches and the Pembrokeshire Coast Path, the 13th-century Tenby Town Walls, me ...

Pembrokeshire Pembrokeshire ( ; ) is a Principal areas of Wales, county in the South West Wales, south-west of Wales. It is bordered by Carmarthenshire to the east, Ceredigion to the northeast, and otherwise by the sea. Haverfordwest is the largest town and ...

, in

Wales Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...

. Recorde entered the

University of Oxford The University of Oxford is a collegiate university, collegiate research university in Oxford, England. There is evidence of teaching as early as 1096, making it the oldest university in the English-speaking world and the List of oldest un ...

about 1525, and was elected a Fellow of All Souls College there in 1531. Having adopted medicine as a profession, he went to the

University of Cambridge The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

to take the degree of M.D. in 1545. He afterwards returned to Oxford, where he publicly taught mathematics, as he had done prior to going to Cambridge. He invented the "equals" sign, which consists of two horizontal parallel lines, stating that no two things can be more equal. It appears that he afterwards went to London, and acted as physician to King

Edward VI Edward VI (12 October 1537 – 6 July 1553) was King of England and King of Ireland, Ireland from 28 January 1547 until his death in 1553. He was crowned on 20 February 1547 at the age of nine. The only surviving son of Henry VIII by his thi ...

and to Queen Mary, to whom some of his books are dedicated. He was also controller of the Royal Mint and served as Comptroller of Mines and Monies in Ireland. After being sued for defamation by a political enemy, he was arrested for debt and died in the King's Bench Prison, Southwark, by the middle of June 1558.

Publications

Recorde published several works upon mathematical and medical subjects, chiefly in the form of dialogue between master and scholar, such as the following: *'' The Grounde of Artes, teachings the Worke and Practise, of Arithmeticke, both in whole numbers and fractions'' (1543), the first English language book on

algebra Algebra is a branch of mathematics that deals with abstract systems, known as algebraic structures, and the manipulation of expressions within those systems. It is a generalization of arithmetic that introduces variables and algebraic ope ...

. *''The Pathway to Knowledge, containing the First Principles of Geometry ... bothe for the use of Instrumentes Geometricall and Astronomicall, and also for Projection of Plattes'' (London, 1551) *''The Castle of Knowledge, containing the Explication of the Sphere both Celestiall and Materiall, etc.'' (London, 1556) A book explaining Ptolemaic astronomy while mentioning the Copernican heliocentric model in passing. *'' The Whetstone of Witte, whiche is the seconde parte of Arithmeteke: containing thextraction of rootes; the cossike practise, with the rule of equation; and the workes of Surde Nombers'' (London, 1557). This was the book in which the

was introduced within a printed edition. With the publication of this book Recorde is credited with introducing algebra into the Island of Britain with a systematic notation. * A medical work, ''The Urinal of Physick'' (1548), frequently reprinted. Most of those works were written in the form of a

catechism A catechism (; from , "to teach orally") is a summary or exposition of Catholic theology, doctrine and serves as a learning introduction to the Sacraments traditionally used in catechesis, or Christian religious teaching of children and adult co ...

. (here cited p. 131). Several books whose authors are unknown have been attributed to him: ''Cosmographiae isagoge'', ''De Arte faciendi Horologium'' and ''De Usu Globorum et de Statu temporum''.John Hall, "An Historiall Expostulation", p. 60. In ''Early English Poetry, Ballads, and Popular Literature of the Middle Ages'', v. XI. London: T. Richards, 1844

Notes

References

* * James R. Newman (1956). ''The World of Mathematics'' Vol. 1 ''Commentary on Robert Recorde'' * Philip E. B. Jourdain (1913). ''The Nature of Mathematics''; * Gareth Roberts and Fenny Smith, editors (2012). ''Robert Recorde: The Life and Times of a Tudor Mathematician'' (University of Wales Press, distributed by University of Chicago Press) 232 pages * Jack Williams (2011)
''Robert Recorde: Tudor Polymath, Expositor and Practitioner of Computation''
(Heidelberg, Springer) (History of Computing). * J. W. S. Cassels (1976). ''Is This a Recorde?'', The Mathematical Gazette Vol. 60 No. 411 March 1976 p 59-61 * Gordon Roberts (2016)
''Robert Recorde: Tudor Scholar and Mathematician''
(University of Wales Press, Scientists of Wales series).
Frank J. Swetz and Victor J. Katz (2011). "Mathematical Treasures - Robert Recorde's Whetstone of Witte," Convergence (January 2011)

External links

Robert Recorde: the Welshman who invented equality

Robert Recorde
and other Welsh Mathematicians
100 Welsh Heroes – Robert Recorde
This contains numerous quotations from Recorde.
RECORDE (Robert)
in Charles Hutton's ''Mathematical and Philosophical Dictionary''
Robert Recorde's life and works on h2g2Current publisher of Robert Recorde's books in the form of original reproductions
* * {{DEFAULTSORT:Recorde, Robert 1510s births 1558 deaths People from Tenby Welsh scientists Welsh philosophers Alumni of the University of Oxford Alumni of the University of Cambridge Welsh mathematicians 16th-century Welsh medical doctors Fellows of All Souls College, Oxford People imprisoned for debt 16th-century Welsh scientists 16th-century philosophers 16th-century Welsh writers 16th-century Welsh male writers Textbook writers 16th-century mathematicians

Biography

Publications

See also

Notes

References

External links