21. Welcome To Gresham College For eleven years Kempe's proof was widely accepted by Cayley and many others -so it was a great surprise when percy heawood of Durham dropped his 'bombshell http://www.gresham.ac.uk/special lectures/Lect211002.htm

FOUR COLOURS SUFFICE? Robin Wilson, former Visiting Gresham Professor in the History of Mathematics In October 1852, Francis Guthrie, a former student of Augustus De Morgan (professor of mathematics at University College London), was colouring a map of England. He noticed that if neighbouring countries had to be differently coloured, then only four colours were needed. Do four colours suffice for colouring all maps, however complicated?, he wondered. On 23 October of that year, 150 years ago this week, Guthrie's brother Frederick asked De Morgan, who immediately became fascinated with the problem and communicated it to his friends. De Morgan's famous letter of 23 October 1852 to the Irish mathematical physicist Sir William Rowan Hamilton included the following extract. A student of mine asked me today to give him a reason for a fact which I did not know was a fact - and do not yet. [He then described the problem, and gave a simple example of a map for which four colours are needed.] Query: cannot a necessity for five or more be invented? De Morgan also wrote about the problem to the philosopher William Whewell, Master of Trinity College Cambridge, and others. The problem first appeared in print in the middle of an unsigned book review (actually by De Morgan) of Whewell's Philosophy of Discovery. This review contained the following very strange passage:

22. Mathem_abbrev Paul Hamilton, William R Hardy, GH Hasib Abu Kamil al Hasse, Helmut Hawking, StephenHaytham, Abu Ali al Heaviside, Oliver, heawood, percy Heisenberg, Werner http://www.pbcc.cc.fl.us/faculty/domnitcj/mgf1107/mathrep1.htm

Mathematician Report Index Below is a list of mathematicians. You may choose from this list or report on a mathematician not listed here. In either case, you must discuss with me the mathematician you have chosen prior to starting your report. No two students may write a report on the same mathematician. I would advise you to go to the library before choosing your topic as there might not be much information on the mathematician you have chosen. Also, you should determine the topic early in the term so that you can "lock-in" your report topic!! The report must include: 1. The name of the mathematician. 2. The years the mathematician was alive. 3. A biography. 4. The mathematician's major contribution(s) to mathematics and an explanation of the importance. 5. A historical perspective during the time the mathematician was alive. Some suggestions on the historical perspective might be: (a) Any wars etc. (b) Scientific breakthroughs of the time (c) Major discoveries of the time (d) How did this mathematician change history etc.

23. The Four Color Problem And Its Connection To South African Flora In 1890, percy John heawood stated that he had discovered an error inKempe's proofan error so serious that he was unable to repair it. http://www.uwinnipeg.ca/~ooellerm/guthrie/FourColor.html

The Four Color Problem and its connection to South African Flora In the 1850's Francis Guthrie was the first mathematician to formulate the Four Color Problem . He asked whether it is possible to color any map with four or fewer colors so that adjacent regions (those that share a common boundary) are colored differently. At the time when he posed the problem, he was a student at University College in London. He attempted to prove that the counties of any map could be colored in this map with four colors. However, he was not entirely satisfied with his proof, so he mentioned his problem to his brother Frederick, who, in turn, mentioned it to his instructor, the famous Augustus De Morgan (after whom De Morgan's Laws of set theory are named). In a letter dated October 23, 1852, De Morgan mentioned the problem to Sir William Rowan Hamilton (for whom hamiltonian graphs are named). In his response, Hamilton, perhaps displaying his insight into the difficulty of mathematical problems, replied to De Morgan that he did not plan to consider this problem in the near future. Evidently, De Morgan spoke often of this problem with other mathematicians. Indeed, De Morgan is credited with writing an anonymous article in the April 14, 1860, issue of the journal Athenaeum in which he discusses the Four Colour Problem. This is the first known published reference to the problem.

24. Untitled ctyrech barvách. percy John heawood, prednášející v Durhamu,publikoval clánek nazvaný Map colouring theorem . Uvádí v http://natura.baf.cz/natura/2001/8/20010805.html

Z historie matematiky a fyziky (3) zpracovali: Jiøí Svršek, Roman Bartoš Typografické poznámky k matematickým vztahùm jsou uvedeny na konci tohoto textu. 9. Problém ètyø barev Problém ètyø barev pochází od Francise Guthrieho , který byl studentem na University College v Londýnì, kde studoval u De Morgana . Po dokonèení studia zaèal studovat práva, ale jeho bratr Frederick Guthrie se stal také studentem u De Morgana. Frederick Guthrie nejprve vykonával praxi obhájce a v roce 1861 odejel do Jižní Afriky jako profesor matematiky. Zde publikoval nìkolik matematických èlánkù a zaèal se zajímat o botaniku. Jeden druh vøesu [Erica Guthriei] byl pojmenován po nìm. V dobì, kdy Frederick ještì studoval u De Morgana, jeho bratr mu ukázal nìkteré výsledky své práce a také ho požádal, aby ze De Morgana zeptal na možnost dùkazu problému ètyø barev. De Morgan na domnìnku o ètyøech barvách neznal odpovìï, ale 23. øíjna 1852 zaslal dopis Hamiltonovi do Dublinu. Domnìnka o ètyøech barvách spoèívá v následující úloze. Libovolný obrazec je rozdìlen na èásti a každá èást má být obarvena jednou ze ètyø barev tak, aby se na spoleèné hranici èástí nevyskytovaly dvì stejné barvy. De Morgan zaslal nìkolika matematikùm dotaz, zda by nebyli ochotni zabývat se øešením problému ètyø barev.

25. Untitled Alfred Tarski. percy John heawood problém ctyr barev. Obecná algebra. percyJohn heawood - teorie aproximací. Fraktální geometrie topologie. http://natura.baf.cz/natura/2002/12/20021203.html

Významní matematikové v historii (11) zpracovali: Jiøí Svršek, Roman Bartoš Literatura: Turnbull University of St. Andrews. Thomas Jan Stieltjes narozen: 29. prosince 1856 ve Zwolle, Holandsko zemøel: 31. prosince 1894 v Toulouse, Francie Thomas Stieltjes zaèal studovat v roce 1873 na Polytechnické škole v Delftu, ale svá studentská léta strávil samostudiem prací Gausse a Jacobiho, místo aby navštìvoval pøedepsané pøednášky. Proto u zkoušek neuspìl. Když se mu nepodaøilo složit zkoušky ani v roce 1875, ani v roce 1876, zasáhl jeho otec a pøimluvil se u øeditele Leidenské hvìzdárny, který byl jeho pøítelem. Díky tomu se Thomas stal v roce 1877 asistentem Leidenské observatoøe a zaèal si v roce 1882 dopisovat s Hermitem. Celý svùj život Stieltjes vìnoval matematice. V roce 1883, nìkolik mìsícù poté, co se oženil, odešel z místa v observatoøi a zaèal se vìnovat matematickému výzkumu. V lednu 1884 Stieltjes dostal nabídku na místo profesora matematické analýzy na Univerzitì v Groningenu, kterou pøijal. Bohužel, nakonec však jmenován nebyl, protože nemìl dostateènou kvalifikaci. Díky Hermiteovì pomoci ale Univerzita v Leidenu v èervnu 1884 nabídla Stieltjesovi èestný diplom z matematiky a astronomie. V roce 1885 Stieltjes odešel se svojí rodinou do Paøíže a v roce 1889 byl jmenován na místo profesora diferenciálního a integrálního poètu na Univerzitì v Toulouse.

26. Exerpts...Euler This is percy heawood's proof, which he gave shortly after findingthe fallacy in AB.Kempe's supposed proof of the 4color theorem. http://mathforum.org/workshops/sum96/discrete/exce.html

Exerpts from discussion on Euler's proof of the Euler Formula: Re: Euler's proof of Euler's formula? John Conway (conway@math.Princeton.EDU) Thu, 8 Feb 1996 09:04:02 -0500 On Wed, 7 Feb 1996, Andrew Leahy wrote: > I'm looking for an accessible reference for Euler's proof of the Euler-Descartes formula f - e + v = 2 for >convex polyhedra. Also, as long as I have your attention, does anybody know how to use this formula to >prove that five colors are sufficient to draw a map on the sphere? Reading through "Mathematics and the >Imagination" I came across the statement that the proof of this "rests on" Euler's formula. Do you really MEAN "EULER's proof", or just ANY proof of EULER's theorem? Supposing the latter, let me describe the way I taught this here only yesterday morning: View the vertices as towns, one of which is called "Rome", the edges as elevated highways (`roads' or `dykes'), and the faces as fields, except that one is called "the Sea", since it is initially full of water. We suppose the barbarians now start to attack the Roman empire as follows. In the first stage, they successively flood the other fields, each time by breaking a dyke that separates an unflooded field from an already flooded one (or the Sea).

27. Math Forum - Ask Dr. Math In 1879 a British mathematician, Alfred Kempe, published a 'proof' that was acceptedby the mathematics establishment until in 1890 percy heawood of Durham http://mathforum.org/library/drmath/view/52466.html

Associated Topics Dr. Math Home Search Dr. Math The Four Color Map problem Date: 11/11/97 at 23:25:27 From: Lisa Subject: The Four Color Map problem I just need help on what it is and where I can find information on it. I am having trouble finding information on it over the Internet. Thanks a lot. Date: 11/12/97 at 10:00:34 From: Doctor Anthony Subject: Re: The Four Color Map problem You can try the following URL which will then refer you to a great deal of literature on the subject. http://www.treasure-troves.com/books/Four-ColorProblem.html http://mathforum.org/dr.math/ Associated Topics High School History/Biography Middle School History/Biography Search the Dr. Math Library: Find items containing (put spaces between keywords): Click only once for faster results: [ Choose "whole words" when searching for a word like age. all keywords, in any order at least one, that exact phrase parts of words whole words Submit your own question to Dr. Math Math Forum Home Math Library Quick Reference ... Math Forum Search Ask Dr. Math TM http://mathforum.org/dr.math/

28. Web A kvaterniók elmélete alapján fejlesztette ki Grassmann az ndimenziósvektor fogalmát. heawood, percy John (1861-1955). Ipswich http://www.jgytf.u-szeged.hu/tanszek/matematika/speckoll/1998/geometria/web.htm

LOBACSEVSZKIJ HILBERT STEINER PITAGORASZ ... HEAWOOD nyelven. (Kr.e. 290/280-Kr.e.212/211) Az (Kr.e. 262?-190?) Pappos Ptolemaiosz ' nemeuklideszi geometria Bolyai Farkasnak ... hiperbola -ra, ahol Monge Pascal Cauchy, Augustin Louis Sorbonne ... Dandelin, Germinal Pierre foglalkozott. Quetelet Desargues, Girard axonometria 1648-ban jelent meg. Pascal Pappos Elemek Hilbert ... Kempe Foglalkozott Heron Hilbert, David Az A Jordan, Marie Ennemond Camille Francia matematikus, az Kleinre Galois Klein, Felix Jordan ... Galois A Riemann Lambert, Johann Heinrich Legendre, Adrien-Marie Lobacsevszkij, Nikolaj Ivanovics ... Mohr, Georg Mohr levelezett Tschirnhaus Leibniz -zel is. Monge, Gaspard Gauss von Staudt Pappos ... Pascal, Blaise . A Leibniz Pitagorasz (Kr. e. 580/570-500) "pythagoreusi iskola" Az Theano Poincare, Henri Sorbonne divergens sorok ... Hensel Steinitz a (Kr.e. 624?-546?)

29. Untitled percy John heawood. Született 1861 szept. 8. Newport, Shropsire, AngliaMeghalt 1955 jan. 24. Durham, Anglia. Ipswichben az Erzsébet http://www.jgytf.u-szeged.hu/tanszek/matematika/speckoll/2000/negyszin/heawood.h

Percy John Heawood Meghalt: 1955 jan. 24. Durham, Anglia Dirac Vissza a matematikusokhoz

30. Atelier Dar, cum un alt percept cere matematicienilor nu crede fãrã a cerceta , în1890 percy John heawood descoperã o lacunã în raþionamentul lui Kempe. http://www.pcreport.ro/pcrep40/cipu38.html

Un datornic bun platnic Empiriocriticism În 1878, Arthur Cayley prezintã problema cole-gilor din Societatea de Matematicã din Londra ºi în anul urmãtor Arthur Bray Kempe (deºi membru al Societãþii de Matematicã, acesta practica... avocatura) publicã o lucrare ce conþinea demonstraþia cerutã de Guthrie. Sau aºa a pãrut timp de 10 ani. Dar, cum un alt percept cere matematicienilor "nu crede fãrã a cerceta", în 1890 Percy John Heawood descoperã o lacunã în raþionamentul lui Kempe. O eroare banalã, niºte termeni a cãror sumã era 12, nu 0, invalideazã articularea sclipitoarelor idei introduse de avocat într-o demonstraþie completã pentru teorema celor 4 culori. Pentru a ilustra o altã paradigmã extrem de valoroasã: " ", meritã a prezenta exemplul cu ajutorul cãruia Heawood a pus în evidenþã faptul cã raþionamentul lui Kempe este iremediabil incomplet. . Ca în jocurile copilãriei, cînd "urma scapã turma", verificarea acestor configuraþii implicã rezolvarea pozitivã a problemei. Pasul final al demonstraþiei se profila cu limpezime: mai rãmînea de generat

31. WARTIME REGISTRAR: DURHAM (1940-44) no problem at all and more often than not, anyway, what percy did propose Then therewas Emeritus Professor heawood, formerly Professor of Mathematics, who was http://www.dur.ac.uk/Alumni/pubs/d1/df12/niblett.htm

WARTIME REGISTRAR: DURHAM (1940-44) Roy Niblett When it became known that William Angus was about to leave us, the question became urgent who could take over his job - temporarily of course. When I was asked if I would be willing to become Acting Registrar from early 1940, a widely shared assumption was the numbers of students in both Divisions would before long be greatly reduced and that one, more or less imitation, Registrar would be able to cope without too much difficulty - especially if he was given an adequate petrol allowance! In fact I went on acting as Registrar for more than four years and the student population grew fast instead of diminishing, for Britain came to recognise that trained minds - especially those of scientists, engineers, medicals - were of great importance to the war effort. During those fascinating years I learned a great deal about university management and something too about managing human beings. My job, which fortunately enabled me to sleep at home every night, entailed frequent journeys by car between Durham and Newcastle - and at first also, of course, journeys between both places and Riding Mill on the Tyne, where we lived. I grew accustomed to taking the Minutes of Meetings of Senate and Court, and to organising Degree Congregations held in the Castle at Durham or the Great Hall at King’s College, Newcastle. But one of the most fascinating aspects of the work was getting to know and dealing with Eustace Percy (Rector of King’s) and James Duff (Warden of Durham Colleges).

32. StudyWorks! Online : What Is The Maximum Number Of Colors You Should Need To Com any map. Eleven years later, however, a mathematician named percy Johnheawood found an error in Hempe's proof. heawood then proved http://www.studyworksonline.com/cda/content/article/0,,EXP1775_NAV2-95_SAR1795,0

Algebra Explorations Astronomy Biology Chemistry ... NEXT >> What Is the Maximum Number of Colors You Should Need to Complete Any Map? Mathematicians have puzzled over this question for more than a century. The so-called "four-color map problem" gained attention in the 1850's, when a mathematics student in London named Francis Guthrie asked whether it is possible to color any map using four or fewer colors so that regions sharing a common boundary are colored differently. He mentioned this perplexing question to his brother Frederick Guthrie, who in turn mentioned it to his teacher, the famous mathematician Augustus De Morgan. In the years to follow, De Morgan discussed the problem with several other mathematicians who also became intrigued by this seemingly simple problem. In 1879, a British lawyer and amateur mathematician named Alfred Bray Kempe announced that he had proved that no more than four colors would be needed for any map. Eleven years later, however, a mathematician named Percy John Heawood found an error in Hempe's proof. Heawood then proved that any map could be completed with five colors. A Four-Color Proof Finally, in 1976, two math professors at the University of Illinois, Kenneth Appel and Wolfgang Haken, used a computer to help prove that only four colors are necessary to complete any map. They had solved one of the biggest problems in mathematics!

33. Untitled ADAMS, percy G., Travellers and Travel Liars 16001800 (Berkeley University of heawood,Edward, A History of Geographical Discoveries in the Sixteenth and http://members.tripod.com/~warlight/KAMIL_16.html

BIBLIOGRAPHY ABBOTT, G.F., Turkey in Transition (London: Edward Arnob, 1909) ADAMS, Percy G., Travel Literature and the Evolution of the Novel (Kentucky: The University Press of Kentucky, 1983) ADAMS, Percy G., Travellers and Travel Liars 1600-1800 (Berkeley: University of California Press, 1962) ADDISON, Joseph and Richard Steele, The Spectator (1715) ed. Gregory Smith (4 vols.), rpt. (London: Dent and Sons, 1964) AGMON, Marcy, “Defending the Upper Gulf: Turkey’s Forgotten Partnership” in Journal of Contemporary History, vol.21, no.1, January 1986, pp.81-97 AHMAD, Feroz, The Young Turks: The Committee of Union and Progress in Turkish Politics 1908-1914 (Oxford: Clarendon Press, 1969) AKSOY, Yildiz, The Turks in Eighteenth Century English Theatre Unpub. Diss. (Erzurum: Ataturk University, 1970) ALBINSKI, Nan Bowman, “Thomas and Peter: Society and Politics in Four British Utopian Novels” in Utopian Studies, vol. 1, 1987, pp.11-2 ALLEN, Henry Elissa, The Turkish Transformation (New York: Greenwood, 1935) AMBLER, Eric, Journey Into Fear, (Glasgow: Fontana/Collins, 1966)

34. Full Alphabetical Index Translate this page 1189*) Hausdorff, Felix (345*) Hawking, Stephen (1282*) Haytham, Abu Ali al (2490*)Heath, Thomas (199*) Heaviside, Oliver (1209*) heawood, percy (596*) Hecht http://www.maththinking.com/boat/mathematicians.html

Full Alphabetical Index Click below to go to one of the separate alphabetical indexes A B C D ... XYZ The number of words in the biography is given in brackets. A * indicates that there is a portrait. A Abbe , Ernst (602*) Abel , Niels Henrik (2899*) Abraham bar Hiyya (641) Abraham, Max Abu Kamil Shuja (1012) Abu Jafar Abu'l-Wafa al-Buzjani (1115) Ackermann , Wilhelm (205) Adams, John Couch Adams, J Frank Adelard of Bath (1008) Adler , August (114) Adrain , Robert (79*) Adrianus , Romanus (419) Aepinus , Franz (124) Agnesi , Maria (2018*) Ahlfors , Lars (725*) Ahmed ibn Yusuf (660) Ahmes Aida Yasuaki (696) Aiken , Howard (665*) Airy , George (313*) Aitken , Alec (825*) Ajima , Naonobu (144) Akhiezer , Naum Il'ich (248*) al-Baghdadi , Abu (947) al-Banna , al-Marrakushi (861) al-Battani , Abu Allah (1333*) al-Biruni , Abu Arrayhan (3002*) al-Farisi , Kamal (1102) al-Haitam , Abu Ali (2490*) al-Hasib Abu Kamil (1012) al-Haytham , Abu Ali (2490*) al-Jawhari , al-Abbas (627) al-Jayyani , Abu (892) al-Karaji , Abu (1789) al-Karkhi al-Kashi , Ghiyath (1725*) al-Khazin , Abu (1148) al-Khalili , Shams (677) al-Khayyami , Omar (2140*) al-Khwarizmi , Abu (2847*) al-Khujandi , Abu (713) al-Kindi , Abu (1151) al-Kuhi , Abu (1146) al-Maghribi , Muhyi (602) al-Mahani , Abu (507) al-Marrakushi , ibn al-Banna (861) al-Nasawi , Abu (681) al-Nayrizi , Abu'l (621) al-Qalasadi , Abu'l (1247) al-Quhi , Abu (1146) al-Samarqandi , Shams (202) al-Samawal , Ibn (1569) al-Sijzi , Abu (708) al-Tusi , Nasir (1912) al-Tusi , Sharaf (1138) al-Umawi , Abu (1014) al-Uqlidisi , Abu'l (1028) Albanese , Giacomo (282) Albategnius (al-Battani) (1333*)

35. The Four Colour Theorem Colour Conjecture in 1890. percy John heawood, a lecturer at DurhamEngland, published a paper called Map colouring theorem. In it he http://math.5u.com/The four colour theorem.htm

Cheap Web Site Hosting The four colour theorem The Four Colour Conjecture first seems to have been made by Francis Guthrie . He was a student at University College London where he studied under De Morgan . After graduating from London he studied law but by this time his brother Frederick Guthrie had become a student of De Morgan . Francis Guthrie showed his brother some results he had been trying to prove about the colouring of maps and asked Frederick to ask De Morgan about them. De Morgan was unable to give an answer but, on 23 October 1852, the same day he was asked the question, he wrote to Hamilton in Dublin. De Morgan wrote:- A student of mine asked me today to give him a reason for a fact which I did not know was a fact - and do not yet. He says that if a figure be anyhow divided and the compartments differently coloured so that figures with any portion of common boundary line are differently coloured - four colours may be wanted, but not more - the following is the case in which four colours are wanted. Query cannot a necessity for five or more be invented. ...... If you retort with some very simple case which makes me out a stupid animal, I think I must do as the Sphynx did.... Hamilton replied on 26 October 1852 (showing the efficiency of both himself and the postal service):- I am not likely to attempt your quaternion of colour very soon.

36. BSHM: Gazetteer -- N Can anyone provide more details Newport, Shropshire. percy John heawood (18611955)was born here Biggs, Lloyd Wilson, p. 217. Newton Abbot, Devon. http://www.dcs.warwick.ac.uk/bshm/zingaz/N.html

The British Society for the History of Mathematics HOME About BSHM BSHM Council Join BSHM ... Search BSHM Gazetteer N Main Gazetteer A B C D ... Z Written by David Singmaster (zingmast@sbu.ac.uk ). Links to relevant external websites are being added occasionally to this gazetteer but the BSHM has no control over the availability or contents of these links. Please inform the BSHM Webster (A.Mann@gre.ac.uk) of any broken links. [When the gazetteer was edited for serial publication in the BSHM Newsletter, references were omitted since the bibliography was too substantial to be included. Publication on the web permits references to be included for material now being added to the website, but they are still absent from material originally prepared for the Newsletter - TM, August 2002] Nelson, Lancashire Newcastle-under-Lyme, Staffordshire Newcastle-upon-Tyne Tyne and Wear ... Return to the top. Dafydd Nanmor lived in the early 15th Century at Nanmor (probably Nantmor ) on the south side of Mt. Snowdon - he was a poet and "was fond of puzzles, astronomy, and grammar" [Beazley & Howell, p. 153]. Nelson, Lancashire

37. BSHM Gazetteer Oxford Individuals percy John heawood (18611955) was a student at Exeter College. Heremained at Oxford until 1887 Biggs, Lloyd Wilson, p.217. http://www.dcs.warwick.ac.uk/bshm/zingaz/OxfordPeople.html

38. Jorma Kypp– ilmestyi jo 1879, mutta tuo Arthur Kempen kuuluisuuta saanut todistus osoitettiinvirheelliseksi yksitoista vuotta myöhemmin 1890 (percy John heawood). http://www.cs.jyu.fi/~jorma/4cc.htm

Verkkoteorian sivulle kromaattinen luku Vuonna 1852 englantilainen opiskelija, Francis Guthrie, esitti kohtalokkaan kysymys: Demot 4: 1.-6. ja 5: 1-2. , 4. Operaatiotutkimuksen ja matematiikan perusteet, Tietojenk”sittelytieteiden laitos, Informaatioteknologian tiedekunta, Jyv”skyl”n yliopisto

39. The Four Color Problem It was only some years later that percy heawood published a papergiving an example for which Kempe's mapcoloring method failed. http://www.ams.org/ams/wilson-jmm2003.html

Robin Wilson: "Four Colors Suffice" - Allyn Jackson, Deputy Editor, Notices of the AMS [This MAA Invited Address was given January 15, 2003.] More highlights of the 2003 Joint Mathematics Meetings Comments: webmaster@ams.org Privacy Statement

40. Math G Mission College Santa Clara In 1890 The Four Color Theorem, once again, became the Four Color Conjecturewhen percy John heawood revealed errors in Kempeís proof. http://www.missioncollege.org/depts/math/beard2.htm

Math Department, Mission College, Santa Clara, California Go to Math Dept Main Page Mission College Main Page This paper was written as an assignment for Ian Walton's Math G - Math for liberal Arts Students - at Mission College. If you use material from this paper, please acknowledge it. To explore other such papers go to the Math G Projects Page. The Four Color Theorem Michelle Beard Math G, Spring 1999 Mission College, Santa Clara How many colors are required to color any map so that no countries with common borders are the same color? It is generally held that four colors, for any flat map, will suffice. But a belief that is commonly held and easily observed, is not a mathematical certainty. Nor does the simplicity of a question reflect the ease with which the answer can be proven. The mathematical evidence to create a valid proof that four colors are all that is required had evaded mathematicians for nearly 140 years. What became known as the Four Color Conjecture has been the cause of great fascination and frustration. It has also been the stimulus for new ideas in topology, knot theory, and the concept of mathematical proof. Historical Overview: The question was originally posed by Francis Guthrie, a former student of the famous mathematician Augustus De Morgan, in 1852. Although Francis moved on to study law, his brother Frederick Guthrie had become a student of De Morgan. Francis Guthrie presented his work on the idea to his brother asking that he pass it along to De Morgan.

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