Omar Khayyám

For the Thoroughbred racehorse see Omar Khayyam (horse)

Ghiyāth ad-Dīn Abul-Fat'h Umar ibn Ibrāhīm Khayyām Neyshābūri (Persian: غیاث الدین ابو الفتح عمر بن ابراهیم خیام نیشابوری) (born Nishapur, Persia, May 18, 1048 – died December 4, 1122), mostly known as Omar Khayyam (Persian: عمر خیام) was a Persian[1] poet, mathematician, philosopher and astronomer who lived in Persia. His name is also given as Omar al-Khayyami.[2]

Omar Khayyám
Omar Chayyam.jpg
Portrait of Khayyam at his Mausoleum in Nishapur
Full name Omar Khayyám
Birth May 18, 1048
Death December 4, 1122
School/tradition Persian mathematics, Persian poetry, Persian philosophy
Main interests Poetry, Mathematics, Philosophy, Astronomy
Influenced by

He is best known for his poetry, and outside Iran, for the quatrains (rubaiyaas) in Rubaiyat of Omar Khayyam, popularized through Edward Fitzgerald's re-created translation. His substantial mathematical contributions include his Treatise on Demonstration of Problems of Algebra, which gives a geometric method for solving cubic equations by intersecting a hyperbola with a circle.[3] He also contributed to calendar reform and may have proposed a heliocentric theory well before Copernicus (but over 1000 years after Aristarchus of Samos).

Contents

Early life

Khayyam was born in Nishapur, Iran, then a Seljuk capital in Khorasan (present Northeast Iran), rivaling Cairo or Baghdad. He was a Sunni Muslim.[4][5] He is thought to have been born into a family of tent makers (literally, al-khayyami means "tent maker"); later in life he would make this into a play on words:

Khayyam, who stitched the tents of science,
Has fallen in grief's furnace and been suddenly burned,
The shears of Fate have cut the tent ropes of his life,
And the broker of Hope has sold him for nothing![3]

He spent part of his childhood in the town of Balkh (present northern Afghanistan), studying under the well-known scholar Sheik Muhammad Mansuri. Subsequently, he studied under Imam Mowaffaq Nishapuri, who was considered one of the greatest teachers of the Khorassan region.

According to a well-known legend called Three Schoolmates, two other exceptional students studied under the Imam Mowaffaq at about the same time: Nizam-ul-Mulk (b. 1018), who went on to become the Vizier to the Seljukid Empire, and Hassan-i-Sabah (b.1034), who became the leader of the Hashshashin (Nizar Ismaili) sect. It was said that these students became friends, and after Nizam-ul-Mulk became Vizier, Hassan-i-Sabah and Omar Khayyám each went to him, and asked to share in his good fortune. Hassan-i-Sabah demanded and was granted a place in the government, but he was ambitious, and was eventually removed from power after he participated in an unsuccessful effort to overthrow his benefactor, the Vizier. Omar Khayyám was more modest and asked merely for a place to live, study science, and pray. He was granted a yearly pension of 1,200 mithkals of gold from the treasury of Nishapur. He lived on this pension for the rest of his life.

The authenticity of this legend is dubious and is rejected by many scholars (e.g. Foroughi and Aghaeipour),[6] in part due to the 30 year age difference between Khayyam and Nizam-ul-Mulk, which makes it unlikely for the two to have attended school together, also considering the fact that the three men grew up in different parts of the country. The popularity and spread of the legend however, is notable and could perhaps be explained by the fact that the three men were the most prominent figures of their time and represented three dominant approaches to reform and betterment of the society, namely, scientific discovery, represented by Khayyam, armed rebellion, represented by Hassan-i-Sabah, and strengthening the power establishment and the rule of law and order, represented by Nizam-ul-Mulk.

Mathematician

Tomb of Omar Khayyam in Neishapur, Iran.

Omar Khayyam was famous during his times as a mathematician. He wrote the influential Treatise on Demonstration of Problems of Algebra (1070), which laid down the principles of algebra, part of the body of Persian Mathematics that was eventually transmitted to Europe. In particular, he derived general methods for solving cubic equations and even some higher orders:

From the Indians one has methods for obtaining square and cube roots, methods which are based on knowledge of individual cases, namely the knowledge of the squares of the nine digits 12, 22, 32 (etc.) and their respective products, i.e. 2 × 3 etc. We have written a treatise on the proof of the validity of those methods and that they satisfy the conditions. In addition we have increased their types, namely in the form of the determination of the fourth, fifth, sixth roots up to any desired degree. No one preceded us in this and those proofs are purely arithmetic, founded on the arithmetic of The Elements. - Omar Khayyam: Treatise on Demonstration of Problems of Algebra[7]

His method for solving cubic equations worked by intersecting a conic section with a circle (examples[8]). Although this approach had been used earlier by Menaechmus and others, Khayyám provided a generalization extending it to all cubics with positive roots. In addition he discovered the binomial expansion. His method for solving quadratic equations is also similar to what is used today.

Also, he was the first Persian mathematician to call the unknown factor of an equation (i.e., the x) shay (meaning thing or something in Arabic). This word was transliterated to Spanish during the Middle Ages as xay, and, from there, it became popular among European mathematicians to call the unknown factor either xay, or more usually by its abbreviated form, x, which is the reason why nowadays unknown factors are usually represented by an x.[9]

In the Treatise he also wrote on the triangular array of binomial coefficients known as Pascal's triangle. In 1077, Omar wrote Sharh ma ashkala min musadarat kitab Uqlidis (Explanations of the Difficulties in the Postulates of Euclid). An important part of the book is concerned with Euclid's famous parallel postulate, which had also attracted the interest of Thabit ibn Qurra. Al-Haytham had previously attempted a demonstration of the postulate; Omar's attempt was a distinct advance, and his criticisms made their way to Europe, and may have contributed to the eventual development of non-Euclidean geometry.

Omar Khayyám also had other notable work in geometry, specifically on the theory of proportions.

Khayyam-Saccheri quadrilateral

The Khayyam-Saccheri quadrilateral was first considered by Omar Khayyam in the late 11th century in Book I of Explanations of the Difficulties in the Postulates of Euclid.[10] Unlike many commentators on Euclid before and after him (including of course Saccheri), Khayyam was not trying to prove the parallel postulate as such but to derive it from an equivalent postulate he formulated from "the principles of the Philosopher" (Aristotle):

Two convergent straight lines intersect and it is impossible for two convergent straight lines to diverge in the direction in which they converge.[11]

Khayyam then considered the three cases right, obtuse, and acute that the summit angles of a Saccheri quadrilateral can take and after proving a number of theorems about them, he (correctly) refuted the obtuse and acute cases based on his postulate and hence derived the classic postulate of Euclid.

It wasn't until 600 years later that Giordano Vitale made an advance on Khayyam in his book Euclide restituo (1680, 1686), when he used the quadrilateral to prove that if three points are equidistant on the base AB and the summit CD, then AB and CD are everywhere equidistant. Saccheri himself based the whole of his long, heroic, and ultimately flawed proof of the parallel postulate around the quadrilateral and its three cases, proving many theorems about its properties along the way.

Astronomer

Like most Persian mathematicians of the period, Omar Khayyám was also famous as an astronomer. In 1073, the Seljuk dynasty Sultan Sultan Jalal al-Din Malekshah Saljuqi (Malik-Shah I, 1072-92), invited Khayyám to build an observatory, along with various other distinguished scientists. Eventually, Khayyám and his colleagues measured the length of the solar year as 365.24219858156 days (correct to six decimal places). This calendric measurement has only an 1-hour error every 5,500 years, whereas the Gregorian Calendar, adopted in Europe four centuries later, has a 1-day error in every 3,330 years, but is easier to calculate.

Calendar reform

Statue of Omar Khayyam in Iran.

Omar Khayyam was part of a panel that introduced several reforms to the Persian calendar, largely based on ideas from the Hindu calendar. On March 15, 1079, Sultan Malik Shah I accepted this corrected calendar as the official Persian calendar.[12]

This calendar was known as Jalali calendar after the Sultan, and was in force across Greater Iran from the 11th to the 20th centuries. It is the basis of the Iranian calendar which is followed today in Iran and Afghanistan. While the Jalali calendar is more accurate than the Gregorian, it is based on actual solar transit, (similar to Hindu calendars), and requires an Ephemeris for calculating dates. The lengths of the months can vary between 29 and 32 days depending on the moment when the sun crossed into a new zodiacal area (an attribute common to most Hindu calendars). This meant, however, that seasonal errors were lower than in the Gregorian calendar.

The modern-day Iranian calendar standardizes the month lengths based on a reform from 1925, thus minimizing the effect of solar transits. Seasonal errors are somewhat higher than in the Jalali version, but leap years are calculated as before.

Omar Khayyám also built a star map (now lost), which was famous in the Persian and Islamic world

Heliocentric theory

It is said that Omar Khayyam also estimated and proved to an audience that included the then-prestigious and most respected scholar Imam Ghazali, that the universe is not moving around earth as was believed by all at that time. By constructing a revolving platform and simple arrangement of the star charts lit by candles around the circular walls of the room, he demonstrated that earth revolves on its axis, bringing into view different constellations throughout the night and day (completing a one-day cycle). He also elaborated that stars are stationary objects in space which, if moving around earth, would have been burnt to cinders due to their large mass. Some of these ideas may have been transmitted to Western science after the Renaissance.

Poet

Main article: Rubaiyat of Omar Khayyam

Omar Khayyám's poetic work has eclipsed his fame as a mathematician and scientist.

He is believed to have written about a thousand four-line verses or quatrains (rubaai's). In the English-speaking world, he was introduced through the The Rubáiyát of Omar Khayyám which are rather free-wheeling English translations by Edward Fitzgerald (1809-1883).

Other translations of parts of the rubáiyát (rubáiyát meaning "quatrains") exist, but Fitzgerald's are the most well known. Translations also exist in languages other than English.

Ironically, Fitzgerald's translations reintroduced Khayyam to Iranians "who had long ignored the Neishapouri poet." A 1934 book by one of Iran's most prominent writers, Sadeq Hedayat, Songs of Khayyam, (Taranehha-ye Khayyam) is said have "shaped the way a generation of Iranians viewed" the poet.[13]

Omar Khayyam's personal beliefs are not known with certainty, but much is discernible from his poetic oeuvre.

Poetry

(These poems were translated by Edward FitzGerald and are potentially more revealing of the thoughts of Edward than Omar.)

Monument to Omar Khayyám in Bucharest.

And, as the Cock crew, those who stood before
  The Tavern shouted - "Open then the Door!
You know how little time we have to stay,
  And once departed, may return no more."

Alike for those who for TO-DAY prepare,
  And that after a TO-MORROW stare,
A Muezzin from the Tower of Darkness cries
  "Fools! your reward is neither Here nor There!"

Why, all the Saints and Sages who discuss'd
  Of the Two Worlds so learnedly, are thrust
Like foolish Prophets forth; their Words to Scorn
  Are scatter'd, and their mouths are stopt with Dust.

Oh, come with old Khayyam, and leave the Wise
  To talk; one thing is certain, that Life flies;
One thing is certain, and the Rest is Lies;
  The Flower that once has blown for ever dies.

Myself when young did eagerly frequent
  Doctor and Saint, and heard great Argument
About it and about: but evermore
  Came out of the same Door as I went.

With them the Seed of Wisdom did I sow,
  And with my own hand labour'd it to grow:
And this was all the Harvest that I reap'd -
  "I came like Water, and like Wind I go."

Into this Universe, and why not knowing,
  Nor whence, like Water willy-nilly flowing:
And out of it, as Wind along the Waste,
  I know not whither, willy-nilly blowing.

The Moving Finger writes; and, having writ,
  Moves on: nor all thy Piety nor Wit
Shall lure it back to cancel half a Line,
  Nor all thy Tears wash out a Word of it.

And that inverted Bowl we call The Sky,
  Whereunder crawling coop't we live and die,
Lift not thy hands to It for help - for It
  Rolls impotently on as Thou or I.

Views on religion

"At the Tomb of Omar Khayyam", by Jay Hambidge.

Despite a strong Islamic training, it is clear that Omar Khayyam himself was undevout and had no sympathy with popular religion,[14] but was not by any means an atheist, as suggested by the verse: "Enjoy wine and women and don't be afraid, God has compassion". Some religious Iranians have argued that Khayyam's references to intoxication in the Rubaiyat were actually the intoxication of the religious worshiper with his Divine Beloved - a Sufi conceit. This however, is reportedly a minority opinion dismissed as wishful pious thinking by most Iranians.[15]

It is almost certain that Khayyám objected to the notion that every particular event and phenomenon was the result of divine intervention. Nor did he believe in an afterlife with a Judgment Day or rewards and punishments. Instead, he supported the view that laws of nature explained all phenomena of observed life. One hostile orthodox account of him shows him as "versed in all the wisdom of the Greeks" and as insistent that studying science on Greek lines is necessary.[14] He came into conflict with religious officials several times, and had to explain his views on Islam on multiple occasions; there is even one story about a treacherous pupil who tried to bring him into public odium. The contemporary Ibn al Kifti wrote that Omar Khayyam "performed pilgrimages not from piety but from fear" of his contemporaries who divined his unbelief.[14]

Khayyám's disdain of Islam in general and its various aspects such as eschatology, Islamic taboos and divine revelation are clearly visible in his writings, particularly the quatrains, which as a rule reflect his intrinsic conclusions describing those who claim to receive God's word as maggot-minded fanatics (via Le Gallienne's translation):[16]

Allah, perchance, the secret word might spell;
If Allah be, He keeps His secret well;
 What He hath hidden, who shall hope to find?
Shall God His secret to a maggot tell?
...
The Koran! well, come put me to the test—
Lovely old book in hideous error drest—
 Believe me, I can quote the Koran too,
The unbeliever knows his Koran best.
 
And do you think that unto such as you,
A maggot-minded, starved, fanatic crew,
 God gave the secret, and denied it me?—
Well, well, what matters it! believe that too.

Although a great number of quatrains erroneously attributed to Khayyam manifest a more colorful irreligiousness and hedonism, nevertheless, the number of his original quatrains that advocate laws of nature and deny the idea of resurrection and eternal life readily outweigh others that express the slightest devotion or praise to God or Islamic beliefs. The following two quatrains are representative of numerous others that serve to reject many tenets of Islamic dogma:

O Mullah, we (people) do much more work than you,
Even when we are drunk, we are still more sober than you,
You drink people's blood and we drink the grape's blood [wine],
Let's be fair, which one of us is more immoral?
خيام اگر ز باده مستى خوش باش
با ماه رخى اگر نشستى خوش باش
چون عاقبت كار جهان نيستى است
انگار كه نيستى، چو هستى خوش باش

which translates in Fitzgerald's work as:

And if the Wine you drink, the Lip you press,
End in the Nothing all Things end in — Yes —
Then fancy while Thou art, Thou art but what
Thou shalt be — Nothing — Thou shalt not be less.

A more literal translation could read:

If with wine you are drunk be happy,
If seated with a moon-faced (beautiful), be happy,
Since the end purpose of the universe is nothing-ness;
Hence picture your nothing-ness, then while you are, be happy!

آنانكه ز پيش رفته‌اند اى ساقى

درخاك غرور خفته‌اند اى ساقى
رو باده خور و حقيقت از من بشنو
باد است هرآنچه گفته‌اند اى ساقى

which Fitzgerald has boldy interpreted as:

Why, all the Saints and Sages who discuss’d
Of the Two Worlds so learnedly — are thrust
Like foolish Prophets forth; their Words to Scorn
Are scatter’d, and their Mouths are stopt with Dust.

A literal translation, in an ironic echo of "all is vanity", could read:

Those who have gone forth, thou cup-bearer,
Have fallen upon the dust of pride, thou cup-bearer,
Drink wine and hear from me the truth:
(Hot) air is all that they have said, thou cup-bearer.

Legacy

A lunar crater Omar Khayyam was named after him in 1970. A minor planet 3095 Omarkhayyam discovered by Soviet astronomer Lyudmila Zhuravlyova in 1980 is named after him.[17]

In popular culture

Historical fiction

Cultural references

References

  1. ↑ Omar Khayyam. (2008). In Encyclopædia Britannica. Retrieved September 17, 2008, from Encyclopædia Britannica Online: http://www.britannica.com/EBchecked/topic/428267/Omar-Khayyam
  2. ↑ "Omar Khayyam". Encyclopædia Britannica. (2007). Retrieved on 2007-06-09.  Gives his name as Ghiyath al-Din Abu al-Fath 'Umar ibn Ibrahim al-Nisaburi al-Khayyami (the last two differ from the version here), and lists mathematician before poet in his identity.
  3. ↑ 3.0 3.1 "Omar Khayyam". The MacTutor History of Mathematics archive.
  4. ↑ Yahya Armajani, Iran p.81
  5. ↑ Shirlee Emmons, Researching the song p.257
  6. ↑ "Omar Khayam (in Persian)" (PDF). Retrieved on 2008-01-20.
  7. ↑ "Muslim extraction of roots". Mactutor History of Mathematics.
  8. ↑ June Jones. "Omar Khayyam and a Geometric Solution of the Cubic".
  9. ↑ Vid. Amin Maaluf, Samarcande, 1988, and/or http://www-history.mcs.st-andrews.ac.uk/Mathematicians/Khayyam.html
  10. ↑ Boris Abramovich Rozenfelʹd (1988), A History of Non-Euclidean Geometry: Evolution of the Concept of a Geometric Space, p. 65. Springer, ISBN 0387964584.
  11. ↑ Boris A Rosenfeld and Adolf P Youschkevitch (1996), Geometry, p.467 in Roshdi Rashed, Régis Morelon (1996), Encyclopedia of the history of Arabic science, Routledge, ISBN 0415124115.
  12. ↑ "Omar Khayyam". The Columbia Encyclopedia, Sixth Edition.. (2001-05). Retrieved on 2007-06-10. Here Omar Khayyam is described as "poet and mathematician", i.e. poet appearing first.
  13. ↑ Molavi, Afshin, The Soul of Iran, Norton, (2005), p.110
  14. ↑ 14.0 14.1 14.2 Robertson (1914). "Freethought under Islam". A Short History of Freethough, Ancient and Modern Volume I (Elibron Classics). Watts & Co., London. pp. 263. ISBN 0543851907. "A hostile orthodox account of him, written in the thirteenth century, represents him as "versed in all the wisdom of the Greeks," and as wont to insist on the necessity of studying science on Greek lines. Of his prose works, two, which were stand authority, dealt respectively with precious stones and climatology. Beyond question the poet-astronomer was undevout; and his astronomy doubtless helped to make him so. One contemporary writes: "I did not observe that he had any great belief in astrological predictions; nor have I seen or heard of any of the great (scientists) who had such belief." In point of fact he was not, any more than Abu';-Ala, a convinced atheist, but he had no sympathy with popular religion. "He gave his adherence to no religious sect. Agnosticism, not faith, is the keynote of his works." Among the sects he saw everywhere strife and hatred in which he could have no part.". 
  15. ↑ Molavi, Afshin, The Soul of Iran, Norton, (2005), p.110
  16. ↑ Hitchens (2007). The Portable Atheist. Da Capo. pp. 10. ISBN 0306816083. "The most celebrated translation of his immortal Rubáiyát into English was done by Edward Fitzgerald, but the verses rendered by Richard Le Gallienne are sometimes better at conveying the pungency that underlies the ironic charm of these quatrains.". 
  17. ↑ Dictionary of Minor Planet Names - p.255
  18. ↑ Jorge Castañeda: "Compañero: The Life and Death of Che Guevara", page 256. Random House USA Inc, 1998.
  19. ↑ http://www.americanrhetoric.com/speeches/cdarrowpleaformercy.htm

Other references

See also

External links

Islamic mathematics
Mathematicians
'Abd al-Hamīd ibn Turk · Abd al-Rahman al-Sufi · Abū al-Hasan ibn Alī al-Qalasādī · Abū al-Wafā' al-Būzjānī · Abū Ishāq Ibrāhīm al-Zarqālī · Abū Ja'far al-Khāzin · Abū Kāmil Shujā ibn Aslam · Abu'l-Hasan al-Uqlidisi · Abu-Mahmud al-Khujandi · Abu Nasr Mansur · Abū Rayhān al-Bīrūnī · Abū Sahl al-Qūhī · Ahmed ibn Yusuf · Al-Abbās ibn Said al-Jawharī · Al-Birjandi · Al-Hajjāj ibn Yūsuf ibn Matar · Al-Jayyani · Al-Karaji · Al-Khazini · Al-Kindi · Al-Mahani · Al-Nayrizi · Al-Saghani · Al-Sijzi · Alī ibn Ahmad al-Nasawī · Ali Kuşçu · Avicenna · Banū Mūsā · Brethren of Purity · Hunayn ibn Ishaq · Ibn al-Banna al-Marrakushi · Ibn al-Haytham · Ibn al-Shatir  · Ibn Sahl · Ibn Tahir al-Baghdadi · Ibn Yahyā al-Maghribī al-Samaw'al · Ibn Yunus · Ibrahim ibn Sinan · Jamshīd al-Kāshī · Kamāl al-Dīn al-Fārisī · Kushyar ibn Labban · Muhammad Baqir Yazdi · Muhammad ibn Jābir al-Harrānī al-Battānī · Muhammad ibn Mūsā al-Khwārizmī · Muhyi al-Dīn al-Maghribī · Nasīr al-Dīn al-Tūsī · Omar Khayyám · Qāḍī Zāda al-Rūmī · Al-Khalili · Shams al-Dīn al-Samarqandī  · Sharaf al-Dīn al-Tūsī · Sinan ibn Thabit · Taqi al-Din · Thābit ibn Qurra · Ulugh Beg · Yusuf al-Mu'taman ibn Hud
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Influences

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Influenced
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Persondata
NAME Khayyám, Omar
ALTERNATIVE NAMES The Tentmaker; Khayyam, Omar;Chayyām, Omar;Omar-e Khayyam
SHORT DESCRIPTION Persian poet and mathematician
DATE OF BIRTH May 18, 1048
PLACE OF BIRTH Nishapur, Persia (Iran)
DATE OF DEATH December 4, 1131
PLACE OF DEATH