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Persian mathematician, philosopher and prolific writer famous for providing a synthesis of the Greek and Hellenistic tradition into the Muslim world.

Played an important role in introducing the Arabic numeral system to the West.




  • Born: c. 801 in Basra or Kufa, Mesopotamia (now in Iraq)
  • Died: c. 873 in Baghdad, Mesopotamia (now in Iraq)


At least two hundred and sixty books, including:

Geometry (thirty-two books)
Medicine (twenty-two books)
Philosophy (twenty-two books)
Logic (nine books)
Physics (twelve books)

Most have been lost, but a few survive.

On astronomy and astrology (the two were synonymous in those days):

  • The Book of the Judgement of the Stars
    • including: The Forty Chapters, on questions and elections
  • On the Stellar Rays
  • De mutatione temporum, ("On the Changing of the Weather")
    • Several other epistles on weather and meteorology
  • Treatise on the Judgement of Eclipses
  • Treatise on the Dominion of the Arabs and its Duration (used to predict the end of Arab rule)
  • The Choices of Days (on elections)
  • On the Revolutions of the Years (on mundane astrology and natal revolutions)
  • De Signis Astronomiae Applicitis as Mediciam ("On the Signs of Astronomy as applied to Medicine")
  • Treatise on the Spirituality of the Planets

On medicine:

  • De Gradibus

On mathematics:

On cryptography:

  • On Deciphering Cryptographic Messages (in which he introduces the concept of frequency analysis)

Also known as

Full name: Abu Yūsuf Yaʻqūb ibn ʼIsḥāq aṣ-Ṣabbāḥ al-Kindī

In Arabic: أبو يوسف يعقوب بن إسحاق الصبّاح الكندي‎

In Latin: Alkindus.