Severus Sebokht, “Letter to Basil of Cyprus” (ca. 662) on ‘Arabic’ numerals

The first reference to what we today call “Arabic” numerals comes in a letter by the Syriac scholar, Severus Sebokht, in about 662 AD.  The letter is often referenced in the literature, but has never been translated into English.  A German text and translation has been published fairly recently.  The letter itself is preserved in a unique manuscript witness, Paris BNF Syr. 346, which contains a collection of works by Severus Sebokht.  (Elsewhere on this site readers may find translations of Severus “On the Astrolabe” and “On the Constellations”).

A few months ago Daniel Knister wrote to me of his intention to make such an English translation.  He has very kindly made this available to us all, and it may be circulated freely and placed on websites etc.  It’s here:

I’ve also uploaded it to here.

This is a wonderful thing to have at last!  Thank you so much!


An opportunity to translate some of Severus Sebokht

The Syriac scientist Severus Sebokht lived in the mid-7th century in Syria and was possibly the most learned man of his day.  He lived at the great monastery of Kinnesrin, which was noted for Greek studies.  He is the first western writer to refer to what we today call “arabic numerals”. 

Two works by him have been translated into French; On the astrolabe and On the constellations.  The French translation of the former was run into English, and I scanned that and placed it online.  I translated part of the latter and also placed that online.

I also dumped whatever information I had on him online here.

Most of his works have never been published.  A lot of them are to be found in a manuscript in the French National Library in Paris, ms. Syr. 346.  I obtained a PDF of a microfilm of this years ago.

I’ve had an offer today by a chap who is fluent in both Syriac and Arabic to translate some of it.  I think I’ll take him up on this!


A 7th century Syriac mathematician

Before the first world war there was a flourishing of interest in Syriac studies among oriental Christians.  Patriarch Aphram I Barsoum wrote in Arabic a patrology of their works, referenced mainly from manuscripts then existing in Eastern libraries.  This was published but inaccessible by reason of language.  However a few years ago the excellent Matti Moosa translated it into English, and it is available from Gorgias Press under the title of The scattered pearls.  For people interested in Syriac, it is a wonderful resource.  I went and bought a copy, which says something.

It seems that a doctoral student really is going to have a go at some of the works of Severus Sebokht.  This made me look up the entry in Barsoum’s work.  It’s quite impressive, and accessible to few.  This is what Barsoum has to say:

94. Severus Sabukht (d. 667)

Severus was a skillful and famous doctor, a mathematician, a philosopher, nay the first scholar of the church who explored the obscurities of astronomical and natural sciences. He was born at Nisibin in the last quarter of the seventh century, became a monk and was educated in the Monastery of Qenneshrin, where he also acquired that knowledge of Greek and Syriac language and literature and of the Persian language, which made him the goal of seekers of knowledge. He was one of the prominent scholars who was graduated from this famous school, in which he also spent his life teaching philosophy, theology and mathematics, besides the writings of all the Syrian scholars. He was most prominent in astronomy and even excelled the Greeks in this field.1 Many pupils studied under him, the most famous of whom were the Patriarch Athanasius II and Jacob of Edessa. In 638, Severus was consecrated a bishop of the city of Qenneshrin, or, as it was said, of his monastery. He died in 667 at an advanced age. He was assigned the twentieth of July (or according to another calendar the eleventh of September) as the festival day of his commemoration. In the latter calendar, he was called “Severus the Mathematician.”

From the writings of Severus, which cover the fields of theology, philosophy and mathematics, very few have come down to us.

Of his theological writings the following survive:

1.  a treatise on the weeks of Daniel;

2.  an extract on the date of the birth of Our Lord in flesh and in what Greek year he was born;

3.  two letters in seven pages to Sergius, abbot of the Monastery of Khanushia in Sinjar, containing a commentary on the two discourses of Gregory Nazianzen on the Son and the Holy Spirit. In these letters, the name of the author (Severus) was ascribed to his native home Nisibin, which misled Chabot, who thought they belonged to a bishop of Nisibin who was Severus’ namesake.2

His philosophical writings are:

4.  a short treatise on the Analytica Posteriora of Aristotle written in 638 of which only three pages remain;3

5.  extracts in three chapters from his treatise on Hermeneutics,

6.  a letter to his friend Jonas the periodeutes (visiting cleric), explaining some points in the Rhetorica of Aristotle;4

    1 Baumstark, p. 246.
    2 See the three folios in the Brit. Mus. MS. 14547, ninth century.
    3 Brit. Mus. MSS. 17156 and 14460. Also, the Chaldean Library in Mosul MS. 35, sixteenth century, and Cambridge MS. 3287, eighteenth century.
    4 Brit. Mus. MS. 17156, Cambridge MS. 2812, nineteenth century, Dayr al-Sayyida MS. 50. 

7.  a treatise he wrote for some of those who love knowledge, explaining some logical points which had been mentioned in his former letter to Jonas to whom he sent a copy of this treatise;

8.  a letter to the priest Ithalaha, who became a bishop of Nineveh on certain terms in the treatise, De Interpretatione and on arithmetic, surveying, astronomy and music, making the remark that he had written to him a year ago, explaining some canons of the saintly fathers and also praising him because he had sent him copies of the letters of Gregory and Basilius.1

Of his astronomical works we have:

9.  a magnificent treatise on the astrolabe in fifty-two pages, translated into French and published by Nau in 1899;2

10.  a treatise on the signs of the Zodiac, which he wrote in the year 659 or 660, of which only eighteen chapters remain. These chapters were published by Sachau in 1870.3 A few samples of these works exist in a manuscript at the British Museum, such as the habitable and inhabitable portions of the earth, the condition of those living in all its sphere—above and below the measurement of the heaven and the earth and the space between them—and whether the sun moves under or over the earth in the celestial sphere. To this treatise he added in the year 665 from nineteen to twenty-seven answers to astronomical, mathematical and cosmographical questions at the request of the periodeutes Basil of Cyprus.4 This is probably the same treatise which Bar Hebraeus alluded to in his book, Ascent of the Mind;

11.  a letter in eighteen pages addressed to the same Basil on the fourteenth of the lunar month of April 556, about fixing the exact date of Easter;5

    1 Brit. Mus. MS. 14660, ninth-tenth centuries, and Mosul MS. 35.
    2 Paris MS. 346 dated 1309 in the handwriting of the priest Yeshu` Kilo; Berlin MS. 186 in the handwriting of the metropolitan Moses of Tyre dated 1556. For the French translation of Sabukht’s treatise on the astrolabe see F. Nau, “Le traite sur l’astrolabe plan de Severe Sabokt,” Journal Asiatique IX serie, t. XIII, 1899: 56-101 and 238-303. (tr.)
    3 Sachau, Inedita Syriaca, 127-134.
    4 Brit. Mus. MS. 14538, tenth century, and Paris MS. 346.
    5 Berlin MS. 186. [The date 556 should be 665. (tr.)]

12.  three letters, also to Basil, on the science of history, contained in the British Museum manuscript;1

13.  he translated from the Persian into Syriac an abridged exposition of Aristotle’s Interpretatione which had been translated from the original Greek to Persian by Paul the Persian for King Khosrau I,2 to which the monk Severus added the fifth treatise of Aristotle on logic;

14. the translation of Ptolemy’s Tetrapillon on the composition of mathematical speech as is confirmed by an established historical tradition.3

Both Wright and Duval, quoting Assemani, who quoted al-Duwayhi, have erroneously ascribed to him a liturgy in the name of Severus of Qenneshrin, which, in fact, belongs to Severus, bishop of Samosata and abbot of Qenneshrin as has been already mentioned.4

    1 Brit. Mus. MS. 17156.
    2 Dayr al-Sayyida MS. 50.

    3 Paris MS. 346.
    4 Wright, A Short History of Syriac Literature, p. 139, citing Assemani B. O., 2: 463. (tr.)

Someone to work on Severus Sebokht?

The 7th century Syriac father Severus Sebokht has left several scientific and philosophical works behind.  I grew interested in him, enough to acquire a PDF of the main manuscript of his mostly unpublished works, but other things supervened and I never pursued the matter.  There are several unpublished letters in the ms. (BNF Syriac 346), one of which is the earliest mention of what we now call Arabic numbers in the west.  The letter has never been translated, tho.

David Bertaina has posted on the Hugoye list a query about him.  Apparently he has a post-grad. student who read mathematics, and is interested in having a go at his works.  This is very good news, if so, and I have written to encourage him and offer support.