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Brief Summary
Major Contribution
Short Biography
Most Significant Publication
Interesting Fact
Recommended Further Reading
Notes and Refs
About Astro Mundi

Brief Introduction to Al Kindi. Compiled by Mari Garcia and Joy Usher
Brief Summary :
Abu Yusuf Ya'qub ibn Ishaq Al-Kindi (ca. 800-870 CE), known as 'the Philosopher of the Arabs' is today viewed as a bridge between the Greek philosophers and Islamic philosophy. Al-Kindi is noted for his work on philosophical terminology and for developing a vocabulary for philosophical thought in Arabic.

Major Contribution :
Al-Kindi's greatest contribution was his efforts to make Greek thought both accessible and acceptable to a Muslim audience. He was concerned with demonstrating the compatibility between philosophy and natural theology, based on reason and ordinary experience. His work distinguished from revealed or speculative theology, which is based on scripture and religious experiences of various kinds. However, he did state that he believed in revelation, which he thought was a superior source of knowledge to reason because it guaranteed matters of faith, which reason alone could not uncover. He successfully incorporated Aristotelian and neo-Platonist thought into an Islamic philosophical framework. This facilitated the introduction and popularization of Greek philosophy in the Muslim intellectual world.

Short Biography :
Abu Yusuf Ya'qub ibn Ishaq Al-Kindi was born around the year 801 in the city of Kufah in modern Iraq. The city was a centre for Arab culture and learning in the 9th century. Al-Kindi's father was the governor of Kufah, as was his grandfather before him. The family was descended from the Royal Kindah tribe who had wielded power and influence previously, but had lost most of its prominence. The descendants, including Al-Kindi's family, continued to hold prominent court positions in Muslim times.

Al-Kindi began his education in Kufah but then moved to Baghdad to complete his studies. Here he quickly achieved fame for his scholarship and came to the attention of the Caliph al-Ma'mun who was at the time establishing the "House of Wisdom" in Baghdad. The "House of Wisdom" was the repository of the greatest collection of Greek philosophical and scientific works since the Library of Alexandria. Together with his colleagues, Al-Kindi's major responsibilities lay in the translation of these works and building on the knowledge that had been acquired by earlier civilisations. When the Caliph, al-Ma'mun died he was succeeded by his brother and Al-Kindi was employed as tutor to his son. However, the developing rivalry between the scholars at the House of Wisdom as well as the orthodoxy of subsequent Caliphs, impacted on Al-kindi's welfare and his scholarship. It is said that his non-orthodox views resulted in physical beatings and at one time, the temporary confiscation of his library. Al-Kindi was a prolific commentator rather than a translator and his role was to polish and augment translations, often raising pertinent issues that had been taken for granted. Although he was best known as a philosopher, he was also a mathematician and scientist of importance. Al-Kindi died in 873 in Baghdad, Iraq.

Quote :
If it were given to anyone to comprehend the whole condition of the celestial harmony, he would know fully the world of the elements, with all that is contained therein at any place and any time, as knowing the caused from the cause... and whoever has acquired the knowledge of the whole condition of the celestial harmony, will know the past, the present and the future.[1]

Most Significant Publication :
Al-Kindi is best known for his work, On First Philosophy, comprising of four sections. The first section is essentially an exhortation to the reader to honour Greek philosophical wisdom. The second contains Al-Kindi's celebrated discussion of the eternity of the world. The third and fourth establish the existence of a "True One," i.e. God, which is the source of unity in all other things, and consider the inapplicability of language to this True One.

Interesting Fact :
Al-Kindi was a pioneer in cryptography. Cryptography is used today in our technologically advanced societies to ensure the security of ATM cards, computer passwords, and electronic commerce. He gave the first known recorded explanation of cryptanalysis in his work, Manuscript on Deciphering Cryptographic Messages. He is credited with developing the method known as "frequency analysis", whereby variations in the frequency of the occurrence of letters could be analyzed and exploited to break ciphers.

Recommended Further Reading :
Al Kindi
Biography of Al Kindi from Stanford Encyclopedia of Philosophy
BBC Radio 4, In Our Time: Al-Kindi. Melvyn Bragg and guests discuss the life and work of Al-Kindi (broadcast, 28 June, 2012).
Site on Al Kindi by by Islamic Philosophy Online.
PDF extract (21 pages) from Al Kindi's On the Stellar Rays (
PDF preview of Benjamin Dyke's translation of Al Kindi's Forty Chapters (
Wikipedia entry on Al Kindi

Notes and References :
  1 ] Al Kindi, On the Stellar Rays (Back to text)
  Title image shows depiction of Al Kindi on a 1962 Iraqi postage stamp. For details see:  

© Mari Garcia, Joy Usher, June, 2013.