From New World Encyclopedia
Portrait of Al-Kindi

Abū-Yūsuf Ya’qūb ibn Ishāq al-Kindī (c. 801-873 C.E.) (Arabic: أبو يوسف يعقوب ابن إسحاق الكندي) (also known in the Western world by the Latinized version of his name, Alkindus) was known as the first Islamic philosopher, and also as a scientist, mathematician, physician, and a talented musician. Appointed to the House of Wisdom (Bayt el Hikma), in Baghdad, he commissioned Arabic translations of the works of the Greek philosophers, and his commentaries on them are identified with the formative period of Arab philosophy. He was the first to apply philosophical logic to Islamic theology, defining many of the central issues of Islamic philosophy, such as the immortality of the individual soul, the nature of the creation, and the distinction between revealed knowledge and human knowledge. His efforts initiated the debate over whether philosophy had a role in Islamic theology.

Al-Kindī established the tradition that was later developed by Avicenna and Averroes. He consistently tried to demonstrate that philosophy is compatible with orthodox Islam, and admitted revelation as a superior source of knowledge in some matters of faith that could not be established by reason.


Al-Kindī was born in 801 C.E. in Kufa, Iraq, a world center of learning at the time. Al-Kindī's father was the governor of Kufa, as his grandfather had been before him. Al-Kindī was descended from the Kinda tribe, which had migrated from Yemen, united a number of tribes and reached their greatest prominence during the 5th and 6th centuries. He was the only well-known Islamic philosopher of Arab descent. Al-Kindī's education took place first in Kufa, then in Basrah, and finally in Baghdad. He was taught the Qu’ran, mathematics, Arab grammar and literature, fiqh and kalam (speculative theology), and the Greek and Syraic languages. He was known for his beautiful calligraphy and at was later employed as a calligrapher by al-Mutawakkil. Al-Qifti, a medieval Islamic bio-bibliographer, reported that al-Kindī was skilled in the arts of the Greeks, the Persians and the Hindus.

The Caliph al-Ma'mun appointed Al-Kindī to the House of Wisdom (Bayt al Hikma) in Baghdad, a center for the translation of Greek philosophical and scientific texts, established by Ma’mun’s father, Harun al-Rashid, which became the Abbasid center for intellectual development. Al-Mamun built a library of important manuscripts collected from Byzantium, and also set up observatories in the House of Wisdom, where Muslim astronomers could build on earlier knowledge. Al-Kindī worked with al-Khwarzimi and three mathematicians, the Banu Musa brothers.

Al-Ma'mun died in 833 and was succeeded by his brother al-Mu'tasim, who employed al-Kindī to tutor his son Ahmad. Al-Mu'tasim died in 842 and was succeeded by al-Wathiq who, in turn, was succeeded as Caliph in 847 by al-Mutawakkil. Under both these caliphs al-Kindī suffered persecution, either because of internal arguments and rivalry among the scholars in the House of Wisdom, or because of al-Mutawakkil’s intolerance of unorthodox Muslims. In one incident, al-Kindī was beaten and his library temporarily confiscated. He died in 873 C.E. during the reign of al-M‘utamid.

Thought and Works

Al-Kindī was the only Islamic philosopher of Arab descent and is often referred to as the “Arab philosopher.” He was a forerunner of Avicenna and Averroes in studying Greek philosophy and attempting to synthesize Aristotelian philosophy and Islamic theology.

Al-Kindī wrote 241 books, including works on geometry (32 books), medicine and philosophy (22two books each), logic (nine books), and physics (12 books), astronomy (16 books), arithmetic (11 books), psychology (five books) and art and music (seven books). In addition, he wrote monographs on the tides, astronomical instruments, rocks and precious stones. Many of his books have been lost. During the Middle Ages, Gerard of Cremona translated Risalah dar Tanjim, Ikhtiyarat al-Ayyam, Ilahyat-e-Aristu, al-Mosiqa, Mad-o-Jazr, and Aduiyah Murakkaba into Latin, and the Scholastics studied De intellectu (On the Intellect). Others have been discovered in Arabic manuscripts—24 of his lost works were rediscovered in the mid-twentieth century, including A Manuscript on Deciphering Cryptographic Messages, a treatise on cryptology, discussing methods of cryptanalysis, encipherments, and statistical analysis of letters and letter combinations in Arabic.

One of the purposes of the House of Wisdom was to make foreign sciences available to Arab scholars through large-scale translation of Greek documents. It is generally accepted that Al-Kindī did not read Greek himself, but corrected, edited and commented on texts prepared by Arabic translators. Al-Kindī emphasized the importance of philosophy and the use of reason over the traditional Qur’anic studies and the study of Arabic grammar, and this position may have attracted persecution during the reign of the more conservative caliphs al-Wathiq and al-Mutawakkil.

We ought not to be embarrassed about appreciating the truth and obtaining it wherever it comes from, even if it comes from races distant and nations different from us. Nothing should be dearer to the seeker of truth than the truth itself, and there is no deterioration of the truth, nor belittling either of one who speaks it or conveys it. (Al-Kindī)


Al-Kindī introduced and popularized Greek philosophy in the Muslim intellectual world. His work on definitions, Fi Hudud al-Ashya’ Wa-Rusumiha (On the Definitions of Things and their Descriptions), was the origin of many standard Arabic philosophical terms (in the eleventh century, this work was superseded by Avicenna’s Book of Definitions, which was more sophisticated ontologically).

Al-Kindī also initiated the debate over whether philosophy had a place in the world of Islamic theology. He consistently tried to demonstrate that philosophy is compatible with orthodox Islam, avoiding the discussion of certain topics such as the resurrection, the last day and the last judgment. Though he rejected speculative theology (kalam), he admitted revelation as a superior source of knowledge in some matters of faith that could not be established by reason.


Al-Kindī’s best known metaphysical treatise is Fi al-Falsafa al-Ula (On First Philosophy). He drew heavily on Aristotle, but his ideas also show the influences of Plato, Porphyry and Proclus. On First Philosophy describes the “first philosophy” as knowledge of the first truth, which includes the first cause of every truth. The first cause has priority over time because it is the cause of time. Like Aristotle, Al-Kindī argued that by studying the natural world, man can acquire knowledge of the divinity and the unity of God. Al-Kindī emphasized the importance of the intellect (‘aql) and its relationship to matter, explaining that the intellect continued after the death of the physical body. He stated that the One Truth (God) does not have attributes, characteristics, or predicates. Al-Kindī differed from the Hellenistic tradition in arguing for creation ex nihilo, saying that matter, time and movement are finite and have a definite beginning, and an end at some future point.


Al-Kindī emphasized the pursuit of serenity in the present life through self-discipline and the exercise of reason, rather than rewards in the afterlife. It is possible that he was influenced by Stoic ideas, particularly those of Epictetus, which were familiar to the Islamic world of that time through contact with Syriac scholars. In a treatise, Fi al-hila li-daf‘ al-ahzan (On the Art of Averting Sorrows), of questionable authenticity, al-Kindī urged his audience to concentrate on the development of the mind and the soul, rather than on the life of the body. He emphasized that the true value of a person lies in the soul, not the body. Attachment to objects in the physical world, he said, would ultimately lead to unhappiness, because such objects could be lost or destroyed. In On the Definitions of Things and their Descriptions, al-Kindī listed the virtues as wisdom, courage and temperance, each one being a midpoint between two extremes (for example, courage was midway between the extremes of rashness and timidity).

Medicine, Mathematics, Natural Science

As a physician, al-Kindī was the first pharmacologist to determine and apply a correct dosage for most of the drugs available at the time. As an advanced chemist, he was an opponent of alchemy and rejected the myth that simple, base metals could be transformed into precious metals such as gold or silver. His works on arithmetic included manuscripts on Indian numbers, the harmony of numbers, lines and multiplication with numbers, relative quantities, measuring proportion and time, and numerical procedures and cancellation. Al-Kindī also popularized the Hindu-Arabic numerals among the Arabs. He ‘proved’ that space and time were finite, with a paradox of the infinite. In geometry, he wrote a text on the theory of parallels, and he wrote two works on optics which later influenced Francis Bacon. At that time little was known about the scientific aspects of music; al-Kindī pointed out that each of the various notes that combine to produce harmony has a specific pitch, and that the degree of harmony depends on the frequency of the notes. He also demonstrated that when a sound is produced, it generates waves in the air, which strike the eardrum, and suggested a way to determine pitch. He also wrote on astronomy and geography.

It is good ... that we endeavour in this book, as is our habit in all subjects, to recall that concerning which the Ancients have said everything in the past, that is the easiest and shortest to adopt for those who follow them, and to go further in those areas where they have not said everything... (Al-Kindī)

ISBN links support NWE through referral fees

  • Arrington, Robert L. A Companion to the Philosophers. Oxford, Blackwell: 2001. ISBN 0631229671
  • King, Peter J. One Hundred Philosophers. New York: Barron's, 2004. ISBN 0764127918
  • Klein-Franke, F. "Al-Kindi," in S. H. Nasr and O. Leaman (eds.)., History of Islamic Philosophy, chap. 11, pp. 165–177. London: Routledge, 1996.
  • Lindberg, David C. Theories of Vision from Al-Kindi to Kepler. University of Chicago Press, 1996.
  • Viegas, Jennifer. Al Kindi: Father of Arab Philosophy and Ninth-century Scientist, Calligrapher, And Musician. Rosen Central, 2006.

External links

All links retrieved June 17, 2023.

  • Al-Kindi – School of Mathematics and Statistics, University of St. Andrews, Scotland
  • Al-Kindi – Islamic Philosophy Online
  • Al-Kindi –

General Philosophy Sources


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