Robert Recorde

{{short description|Welsh mathematician and inventor of the equals sign}}

{{Use dmy dates|date=July 2020}}

{{Use British English|date=July 2020}}

{{Infobox scientist

| name = Robert Recorde

| image = Robert Recorde @ St Mary, Tenby (geograph 6264760).jpg

| caption = Robert Recorde (c.1512–1558)

| birth_date = {{circa|1510}}

| birth_place = Tenby, Pembrokeshire, Wales

| death_date = {{death-date|June 1558}}

| death_place = London, England

| citizenship =

| nationality = Welsh

| ethnicity =

| fields = Physician and mathematician

| workplaces = University of Oxford
Royal Mint

| alma_mater = University of Oxford
University of Cambridge

| doctoral_advisor =

| academic_advisors =

| doctoral_students =

| notable_students =

| known_for = Inventing the equals sign (=)

| influences =

| influenced =

| awards =

| signature =

| footnotes =

}}

Robert Recorde ({{c.|1510 – 1558}}) was a Welsh{{Cite news |last=Mazur |first=Joseph |date=2014-05-21 |title=Notation, notation, notation: a brief history of mathematical symbols |language=en-GB |work=The Guardian |url=https://www.theguardian.com/science/alexs-adventures-in-numberland/2014/may/21/notation-history-mathematical-symbols-joseph-mazur |access-date=2023-05-05 |issn=0261-3077}}Western Mail, Saturday 24 March 1928 - https://www.britishnewspaperarchive.co.uk/viewer/bl/0000104/19280324/188/0006 physician and mathematician. He invented the equals sign (=) and also introduced the pre-existing plus (+) and minus (−) signs to English speakers in 1557.

Biography

Born around 1510, Robert Recorde was the second and last son of Thomas and Rose Recorde{{Cite web|title=Robert Recorde: the Welshman who invented equality|url=https://www.thenational.wales/news/19900552.robert-recorde-welshman-invented-equals-sign/|access-date=2022-02-06|website=The National Wales|language=en|archive-date=6 February 2022|archive-url=https://web.archive.org/web/20220206174552/https://www.thenational.wales/news/19900552.robert-recorde-welshman-invented-equals-sign/|url-status=dead}} of Tenby, Pembrokeshire, in Wales.{{cite ODNB|first=Stephen|last=Johnston|title=Recorde, Robert (c. 1512–1558)|year=2004|url=http://www.oxforddnb.com/view/article/23241|access-date=26 January 2012|doi=10.1093/ref:odnb/23241}}

Recorde entered the University of Oxford 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 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 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.{{cite book|last=Newman|first=James R.|year=1956|title=The World of Mathematics|url=https://archive.org/details/worldofmathemati00newm|url-access=registration}} 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

Image:First Equation Ever.png. (The solution is x = 4)]]

Image:Recorde - The Whetstone of Witte - equals.jpg in The Whetstone of Witte, "to avoid tedious repetition".]]

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.
  • 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 equals sign 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.{{cite book|last=Jourdain|first=Philip E. B.|year=1913|title=The Nature of Mathematics|url=https://archive.org/details/thenatureofmath00jouruoft}}Robert Recorde, The Whetstone of Witte (London, England: John Kyngstone, 1557), [https://archive.org/stream/TheWhetstoneOfWitte#page/n237/mode/2up p. 236] (although the pages of this book are not numbered). From the chapter titled "The rule of equation, commonly called Algebers Rule" (p. 236): "Howbeit, for easie alteration of equations. I will propounde a fewe examples, bicause the extraction of their rootes, maie the more aptly bee wroughte. And to avoide the tediouse repetition of these woordes: is equalle to: I will sette as I doe often in worke use, a paire of paralleles, or Gemowe [twin, from gemew, from the French gemeau (twin / twins), from the Latin gemellus (little twin)] lines of one lengthe, thus: = , bicause noe .2. thynges, can be moare equalle." (However, for easy manipulation of equations, I will present a few examples in order that the extraction of roots may be more readily done. And to avoid the tedious repetition of these words "is equal to", I will substitute, as I often do when working, a pair of parallels or twin lines of the same length, thus: = , because no two things can be more equal.)
  • A medical work, The Urinal of Physick (1548), frequently reprinted.[https://books.google.com/books?id=Sax491XagIgC ''The Urinal of Physick], by Robert Recorde, 1548; at Google Books

Most of those works were written in the form of a catechism.{{cite journal|first1=David Eugene|last1=Smith|author-link1=David Eugene Smith|title=Medicine and Mathematics in the Sixteenth Century|pmc=7927718|pmid= 33943138|journal=Ann. Med. Hist.|date=July 1, 1917|volume= 1|issue=2|pages=125–140|oclc=12650954}} (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

See also

Notes

{{Reflist}}

References

  • {{EB1911|wstitle=Recorde, Robert |volume=22|page=966}}
  • James R. Newman (1956). The World of Mathematics Vol. 1 Commentary on Robert Recorde
  • Philip E. B. Jourdain (1913). The Nature of Mathematics; {{cite book|title=2013 Dover pbk reprint|url=https://books.google.com/books?id=xB49GYZzc4cC|lccn=2006052118|isbn=9780486458854}}
  • 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). [https://books.google.com/books?id=dTqHIM1ds1kC Robert Recorde: Tudor Polymath, Expositor and Practitioner of Computation] (Heidelberg, Springer) (History of Computing). {{cite book|title=pbk edition|isbn=978-0-85729-861-4}}
  • J. W. S. Cassels (1976). Is This a Recorde?, The Mathematical Gazette Vol. 60 No. 411 March 1976 p 59-61 {{doi|10.2307/3615647}}
  • Gordon Roberts (2016). [https://books.google.com/books?id=GeyVDwAAQBAJ Robert Recorde: Tudor Scholar and Mathematician] (University of Wales Press, Scientists of Wales series). {{cite book|title=pbk edition|isbn=978-1-78316-854-5}}
  • [https://www.maa.org/book/export/html/116921 Frank J. Swetz and Victor J. Katz (2011). "Mathematical Treasures - Robert Recorde's Whetstone of Witte," Convergence (January 2011)]