Editing Isaac Barrow (section)

== Life ==
=== Early life and education ===
[[Image:Barrow - Lectiones habitae in scholiis publicis academiae Cantabrigiensis AD 1664, 1683 - 48461.jpg|thumb|''Lectiones habitae in scholiis publicis academiae Cantabrigiensis AD 1664'']]
Barrow was born in London. He was the son of Thomas Barrow, a linen [[draper]] by trade. In 1624, Thomas married Ann, daughter of William Buggin of North Cray, Kent and their son Isaac was born in 1630. It appears that Barrow was the only child of this union—certainly the only child to survive infancy.  Ann died around 1634, and the widowed father sent the lad to his grandfather, Isaac, the Cambridgeshire J.P., who resided at [[Spinney Abbey]].<ref>'The Abbey Scientists' Hall, A.R. p12: London; Roger & Robert Nicholson; 1966</ref>  Within two years, however, Thomas remarried; the new wife was Katherine Oxinden, sister of Henry Oxinden of Maydekin, Kent. From this marriage, he had at least one daughter, Elizabeth (born 1641), and a son, Thomas, who apprenticed to Edward Miller, skinner, and won his release in 1647, emigrating to Barbados in 1680.<ref>{{cite book|last1=Cheesman|first1=Francis|title=Isaac Newton's Teacher|date=2005|publisher=Trafford Publishing|location=Victoria, BC, Canada|isbn=1-4120-6700-6|page=[https://archive.org/details/isaacnewtonsteac0000chee/page/115 115]|edition=first|url=https://archive.org/details/isaacnewtonsteac0000chee/page/115}}</ref>

=== Early career ===
Isaac went to school first at [[Charterhouse School|Charterhouse]] (where he was so turbulent and pugnacious that his father was heard to pray that if it pleased God to take any of his children he could best spare Isaac), and subsequently to [[Felsted School]], where he settled and learned under the brilliant [[puritan]] Headmaster Martin Holbeach who ten years previously had educated [[John Wallis]].<ref>{{cite book |first=M. R. |last=Craze |title=A History of Felsted School, 1564–1947 |publisher=Cowell |year=1955 }}</ref> Having learnt Greek, Hebrew, Latin and logic at Felsted, in preparation for university studies,<ref>{{cite web |first1=J. J. |last1=O'Connor |first2=E. F. |last2=Robertson |work=School of Mathematics and Statistics [[University of St Andrews]] |url=http://www.gap-system.org/~history/Biographies/Barrow.html |title=gap-system |access-date=1 February 2012 |url-status=dead |archive-url=https://web.archive.org/web/20101226042236/http://www.gap-system.org/~history/Biographies/Barrow.html |archive-date=26 December 2010 }}</ref> he continued his education at [[Trinity College, Cambridge]]; he enrolled there because of an offer of support from an unspecified member of the [[Walpole family]], "an offer that was perhaps prompted by the Walpoles' sympathy for Barrow's adherence to the [[Royalist]] cause."<ref>{{cite book |first=Mordechai |last=Feingold |title=Before Newton: The Life and Times of Isaac Barrow |publisher=Cambridge University Press |year=1990 |page=256 |isbn=9780521306942 |url=https://books.google.com/books?id=jR1rxaob2PUC&pg=PA256 }}</ref> His uncle and namesake [[Isaac Barrow (bishop)|Isaac Barrow]], afterwards [[Bishop of St Asaph]], was a Fellow of [[Peterhouse, Cambridge|Peterhouse]].  He took to hard study, distinguishing himself in classics and mathematics; after taking his degree in 1648, he was elected to a fellowship in 1649.<ref>{{acad|id=BRW643I|name=Barrow, Isaac}}</ref> Barrow received an MA from Cambridge in 1652 as a student of [[James Duport]]; he then resided for a few years in college, and became candidate for the Greek Professorship at Cambridge, but in 1655 having refused to sign the [[Engagement controversy|Engagement to uphold the Commonwealth]], he obtained travel grants to go abroad.<ref>{{cite book |title=A Portrait of Isaac Newton |url=https://archive.org/details/portraitofisaacn00manu |url-access=registration |first=Frank E. |last=Manuel |year=1968 |publisher=Belknap Press, MA |page=[https://archive.org/details/portraitofisaacn00manu/page/92 92] }}</ref>

==== Travel ====
He spent the next four years traveling across France, Italy, and Turkey.  In Turkey he lived in Izmir and studied in Istanbul (then called Smyrna and Constantinople), and after many adventures returned to England in 1659. He was known for his courageousness. Particularly noted is the occasion of his having saved the ship he was upon, by the merits of his own prowess, from capture by [[pirate]]s. He is described as "low in stature, lean, and of a pale complexion," slovenly in his dress, and having a committed and long-standing habit of tobacco use (an ''[[Wikt:inveterate|inveterate]] smoker''). In respect to his courtly activities his aptitude to wit earned him favour with [[Charles II of England|Charles II]], and the respect of his fellow courtiers. In his writings one might find accordingly, a sustained and somewhat stately eloquence. He was an altogether impressive personage of the time, having lived a blameless life in which he exercised his conduct with due care and conscientiousness.<ref>D.R. Wilkins –  [[Trinity College, Dublin]] [http://www.maths.tcd.ie/pub/HistMath/People/Barrow/RouseBall/RB_Barrow.html School of Mathematics]. Retrieved 1 February 2012</ref>

=== Later career ===
==== Work ====
On the [[Restoration (England)|Restoration]] in 1660, he was ordained and appointed to the [[Regius Professor of Greek (Cambridge)|Regius Professorship]] of [[Greek language|Greek]] at the [[University of Cambridge]]. In 1662, he was made professor of [[geometry]] at [[Gresham College]], and in 1663 was selected as the first occupier of the [[Lucasian Professor of Mathematics|Lucasian chair]] at Cambridge. During his tenure of this chair he published two mathematical works of great learning and elegance, the first on geometry and the second on optics. In 1669 he resigned his professorship in favour of [[Isaac Newton]].<ref>For a summary of the Barrow–Newton relationship, see {{cite book |author=Gjersten, Derek |title=The Newton Handbook |year=1986 |location=London |publisher=Routledge & Kegan Paul | pages = 54–55}}</ref> About this time, Barrow composed his ''Expositions of the Creed, The Lord's Prayer, Decalogue, and Sacraments''.  For the remainder of his life he devoted himself to the study of [[divinity]]. He was made a [[Doctor of Divinity]] by Royal mandate in 1670, and two years later Master of [[Trinity College, Cambridge|Trinity College]] (1672), where he founded the library, and held the post until his death.

[[Image:StatueOfIsaacBarrow.jpg|thumb|right|Statue of Isaac Barrow in the chapel of [[Trinity College, Cambridge]]]]
His earliest work was a complete edition of the ''Elements'' of [[Euclid]], which he issued in Latin in 1655, and in English in 1660; in 1657 he published an edition of the ''Data''. His lectures, delivered in 1664, 1665, and 1666, were published in 1683 under the title ''Lectiones Mathematicae''; these are mostly on the metaphysical basis for mathematical truths. His lectures for 1667 were published in the same year, and suggest the analysis by which [[Archimedes]] was led to his chief results. In 1669 he issued his ''Lectiones Opticae et Geometricae''. It is said in the preface that Newton revised and corrected these lectures, adding matter of his own, but it seems probable from Newton's remarks in the fluxional controversy that the additions were confined to the parts which dealt with optics. This, which is his most important work in mathematics, was republished with a few minor alterations in 1674. In 1675 he published an edition with numerous comments of the first four books of the ''On Conic Sections'' of [[Apollonius of Perga]], and of the extant works of Archimedes and [[Theodosius of Bithynia]].

In the optical lectures many problems connected with the reflection and refraction of light are treated with ingenuity. The geometrical focus of a point seen by reflection or refraction is defined; and it is explained that the image of an object is the locus of the geometrical foci of every point on it.  Barrow also worked out a few of the easier properties of thin lenses, and considerably simplified the [[René Descartes|Cartesian]] explanation of the [[rainbow]].

Barrow was the first to find the [[integral of the secant function]] in [[Closed-form expression|closed form]], thereby proving a conjecture that was well-known at the time.

==== Death and legacy ====
Barrow died unmarried in London at the early age of 46, and was buried at [[Westminster Abbey]]. [[John Aubrey]], in the [[Brief Lives]], attributes his death to an opium addiction acquired during his residence in Turkey.

Besides the works above mentioned, he wrote other important treatises on mathematics, but in literature his place is chiefly supported by his sermons,<ref>Isaac Barrow, John Tillotson, Abraham Hill – The works of the learned Isaac Barrow ... Printed by J. Heptinstall, for Brabazon Aylmer, 1700 [https://books.google.com/books?id=ZmVZAAAAYAAJ&dq=isaac+barrow+priest&pg=PA217  Published by DR JOHN TILLOTSON THE LORD ARCHBISHOP OF CANTERBURY ]  {&}   Isaac Barrow – The theological works of Isaac Barrow, Volume 1 [https://books.google.com/books?id=_8ctAAAAYAAJ&dq=isaac+barrow+priest&pg=PA318 The University Press, 1830] {&} Isaac Barrow, Thomas Smart Hughes 1831 – ''The Works of Dr. Isaac Barrow: With Some Account of His Life, Summary of Each Discourse, Notes, &c (1831)''- ''Fourth Volume''  [https://archive.org/stream/worksdrisaacbar01hughgoog#page/n5/mode/2up A.J. Valpy]. Retrieved 1 February 2012</ref> which are masterpieces of argumentative eloquence, while his ''Treatise on the Pope's Supremacy'' is regarded as one of the most perfect specimens of controversy in existence. Barrow's character as a man was in all respects worthy of his great talents, though he had a strong vein of eccentricity.