Euclid

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Euclid
Scuola di atene 07.jpg
BornUnknown
DiedUnknown
ResidenceAlexandria, Egypt
FieldsMathematics
Known forEuclidean geometry
Euclid's Elements
 
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Euclid
Scuola di atene 07.jpg
BornUnknown
DiedUnknown
ResidenceAlexandria, Egypt
FieldsMathematics
Known forEuclidean geometry
Euclid's Elements

Euclid (/ˈjuːklɪd/; Ancient Greek: Εὐκλείδης Eukleidēs), fl. 300 BC, also known as Euclid of Alexandria, was a Greek mathematician, often referred to as the "Father of Geometry". He was active in Alexandria during the reign of Ptolemy I (323–283 BC). His Elements is one of the most influential works in the history of mathematics, serving as the main textbook for teaching mathematics (especially geometry) from the time of its publication until the late 19th or early 20th century.[1][2][3] In the Elements, Euclid deduced the principles of what is now called Euclidean geometry from a small set of axioms. Euclid also wrote works on perspective, conic sections, spherical geometry, number theory and rigor.

"Euclid" is the anglicized version of the Greek name Εὐκλείδης, meaning "Good Glory".[4]

Life

Little is known about Euclid's life, as there are only a handful of references to him. The date and place of Euclid's birth and the date and circumstances of his death are unknown, and only roughly estimated in proximity to contemporary figures mentioned in references. Euclid is rarely, if ever, referred to by name by other Greek mathematicians from Archimedes onward, who instead call him "ό στοιχειώτης" ("the author of Elements").[5] The few historical references to Euclid were written centuries after he lived, by Proclus ca. 450 AD and Pappus of Alexandria ca. 320 AD.[6]

Proclus introduces Euclid only briefly in his Commentary on the Elements. According to Proclus, Euclid belonged to Plato's "persuasion" and brought together the Elements, drawing on prior work by several pupils of Plato (particularly Eudoxus of Cnidus, Theaetetus and Philip of Opus.) Proclus believes that Euclid is not much younger than these, and that he must have lived during the time of Ptolemy I because he was mentioned by Archimedes (287-212 BC). Although the purported citation of Euclid by Archimedes has been judged to be an interpolation by later editors of his works, it is still believed that Euclid wrote his works before those of Archimedes.[7][8][9]

Proclus later retells a story that, when Ptolemy I asked if there was a shorter path to learning geometry than Euclid's Elements, "Euclid replied there is no royal road to geometry."[10] This anecdote is questionable since it is similar to a story told about Menaechmus and Alexander the Great.[11]

In the only other key reference to Euclid, Pappus briefly mentioned in the fourth century that Apollonius "spent a very long time with the pupils of Euclid at Alexandria, and it was thus that he acquired such a scientific habit of thought" circa 247-222 BC.[12][13]

A detailed biography of Euclid is given by Arabian authors, mentioning, for example, a birth town of Tyre. This biography is generally believed to be completely fictituous.[8]

Partly due to the lack of biographical information that is somewhat atypical for the period (extensive biographies are available for most significant Greek mathematicians for several centuries before and after Euclid), it has been proposed that Euclid was not, in fact, a historical character, and his works were written by a team of mathematicians (not unlike Bourbaki) who took the name Euclid from the historical character Euclid of Megara. However, this hypothesis is not well accepted by scholars and there is little evidence in its favor.[8][14]

Elements

One of the oldest surviving fragments of Euclid's Elements, found at Oxyrhynchus and dated to circa AD 100 (P. Oxy. 29). The diagram accompanies Book II, Proposition 5.[15]

Although many of the results in Elements originated with earlier mathematicians, one of Euclid's accomplishments was to present them in a single, logically coherent framework, making it easy to use and easy to reference, including a system of rigorous mathematical proofs that remains the basis of mathematics 23 centuries later.[16]

There is no mention of Euclid in the earliest remaining copies of the Elements, and most of the copies say they are "from the edition of Theon" or the "lectures of Theon",[17] while the text considered to be primary, held by the Vatican, mentions no author. The only reference that historians rely on of Euclid having written the Elements was from Proclus, who briefly in his Commentary on the Elements ascribes Euclid as its author.

Although best known for its geometric results, the Elements also includes number theory. It considers the connection between perfect numbers and Mersenne primes, the infinitude of prime numbers, Euclid's lemma on factorization (which leads to the fundamental theorem of arithmetic on uniqueness of prime factorizations), and the Euclidean algorithm for finding the greatest common divisor of two numbers.

The geometrical system described in the Elements was long known simply as geometry, and was considered to be the only geometry possible. Today, however, that system is often referred to as Euclidean geometry to distinguish it from other so-called non-Euclidean geometries that mathematicians discovered in the 19th century.

Other works

Euclid's construction of a regular dodecahedron 
Construction of a dodecahedron basing on a cube

In addition to the Elements, at least five works of Euclid have survived to the present day. They follow the same logical structure as Elements, with definitions and proved propositions.

Other works are credibly attributed to Euclid, but have been lost.

See also

Notes

  1. ^ Ball, pp. 50–62.
  2. ^ Boyer, pp. 100–19.
  3. ^ Macardle, et al. (2008). Scientists: Extraordinary People Who Altered the Course of History. New York: Metro Books. g. 12.
  4. ^ etymonline.com Retrieved 2011-12-04
  5. ^ Heath (1981), p.357
  6. ^ Joyce, David. Euclid. Clark University Department of Mathematics and Computer Science. [1]
  7. ^ Proclus, p. XXX
  8. ^ a b c Euclid of Alexandria
  9. ^ The MacTutor History of Mathematics archive.
  10. ^ Proclus, p. 57
  11. ^ Boyer, p. 96.
  12. ^ Heath (1956), p. 2.
  13. ^ "Conic Sections in Ancient Greece". 
  14. ^ Jean Itard (1962). Les livres arithmétiques d'Euclide. 
  15. ^ Bill Casselman. "One of the Oldest Extant Diagrams from Euclid". University of British Columbia. Retrieved 2008-09-26. 
  16. ^ Struik p. 51 ("their logical structure has influenced scientific thinking perhaps more than any other text in the world").
  17. ^ Heath (1981), p. 360.
  18. ^ Theon article at their institution

References

Further reading

External links