Anania Shirakatsi is one of the greatest scientists who made an important contribution to the field of exact sciences in Armenia, a brilliant scientist and philosopher of the 7th century; actually the founder of exact sciences in Armenian reality.
Unfortunately, out of Shirakatsi’s rich heritage only some fragments of his works in the fields of Mathematics, Cosmography, Calendarology, Metrology, which are of great value for the history of exact sciences, got to us.
There is a valuable source about Anania Shirakatsi’s life and work; the author has left his autobiography.
From Shirakatsi’s autobiography we learn that he was born in the village Aneank (Shirakavan) at the beginning of the 7th century. He got his elementary education in the local monastery school, later being eager to improve his knowledge, he went to West Armenia. Shirakatsi dreamt about specializing especially in Mathematics, which he considered “mother of all sciences”. “And love strongly the art of figures”, he writes, “I thought that it’s not possible to compose something without figures honoring them as the mother of all wisdom”. He had to travel a lot about West Armenia seeking an advanced specialist in Mathematics. He was leaving for Constantinople but on his way to Signup he learns that in Trapeze a great Greek scientist, Tyukhik lives: “a wise man, popular with the kings, an expert on Armenian Language and Literature”. Shirakatsi changed his way and went to Trapeze.
Tyukhik received the young Armenian with pleasure and began to teach him. Shirakatsi remembers his teacher with respect and warmth: “He loved me as his own son, he writes, and he passed all his knowledge with such eagerness that my class-mates were envy”.
Shirakatsi had been at Tyukhik’s school for 8 years; he became proficient in exact science and came back to his native land with rich knowledge base. Here he opened a school and devoted himself to teaching and research. He wrote research works in Astronomy, Mathematics, Geography and in other fields of science. Among medieval sources there is evidence that in 667 – 669 Shirakatsi first, on the instructions of Catholicos Anastas, formed a new Armenian Calendar with the aim to make a fixed one.
Unfortunately not all the works of Anania Shiraktsi have got to us. From the letter, which was written by Armenian scientist of the 11th century Grigor Magistros to Catholicon Petros it is obvious that there was absolutely unfriendly attitude towards Shirakatsi’s scientific work, his works were included among the forbidden books, and Magistros requires from Catholicon to eliminate that injustice.
Out of Shirakatsi’s works got to us the most valuable and unique one is the textbook in Arithmetic which, unfortunately, has got in fragments. It contains addition, subtraction, multiplication tables, “6-hazareak”, 24 tasks and 8 engaging tasks. As it is mentioned in the book “History of Domestic Mathematics”, “On the whole, Shirakatsi’s arithmetic work is the oldest one among the textbooks of Arithmetic known by us and it contains the oldest tables for arithmetic which have got to us. He evidences higher arithmetical literacy in Armenia. Shirakatsi also left a rich heritage on Calendars. His works on Calendarology are of great scientific-historical value. Shirakatsi’s works became the base for Armenian calendar. It is not by chance that almost all great Armenian medieval writers concentrated on Calendarology and remarked the importance of calendars: Hovhannes Draskhanakertsi, Stepanos Taronetsi, Kirakos Gandzaketsi, Vardan Areveltsi, Hakob Ghrimetsi and others.
Among Shirakatsi’s works the most important one is considered “Knnikon”, which contains “Easter Speech”, “Christmas Speech” and “Chronicle” including synchronized spatial tables of changeable and fixed calendars for 532 years. In them in separate graphs month counts of new years, spring equinox, 7-days, important Christian holidays of all years of a certain cycle of both changeable and fixed calendars are written. On the basis of these synchronized tables any Christian holiday date can be clearly defined.
Among Shirakatsi’s calendaric works an important one is “Patchen Tomari”, which is of great value not only on the history of Armenian Calendars but also on the calendars of neighbor nations: such as Egyptians, Jews, Syrians, Persians, Romans, Georgians, Macedonians and others. In this work a calendar is included, which has a close relation with other calendar systems.
Shirakatsi formed a large number of tables and calendar cycles. Among the tables more attractive ones are “Tables of Lunar Cycle” where the exact date of new moon and full moon of the nineteenth-year cycle is given, i.e. the year, the day and the time (in hours and minutes) of new moon and full moon occurring is discovered. And as the nineteenth-year phases of the moon are always repeated then all these tables can be used all the time. Out of Shirakatsi’s calendar cycles the most valuable is so called “Special cycle”, where the monthly movement of the moon through the phases is given, “Orbital Cycle”, where the movement of the moon in the Sun orbit is shown and another astronomical cycle under the name “Shade indicator”, where the duration of the light and the dark at nights of the lunar month are defined.
Shirakatsi’s works on Cosmography are of great value. The basic questions on Exact Sciences are included in it. These works give us an opportunity to learn about his views on Exact Sciences.
Following antique scientists Shirakatsi thinks that the perceptible world and all its substances consist of the four really existing elements: land, water, air and fire. In his opinion the world is “a certain composition of mixed elements”.
Shirakatsi imagines the nature in the process of movement and change. The existing old education decomposes with the time and instead a new one occurs. On the basis of many examples from real life considered as a proof of it he comes to the following philosophic scientific conclusion. “Existence is the beginning of extinction and the extinction is in its turn is the start of existence and as a result of this non-harmful contradiction the world continues to exist.
Shiraktsi’s point of view on Cosmography is also significant. The question related to the earth shape interested the humankind for a long time. Various approaches were expressed in different time periods. In his cosmographic works Shirakatsi gives a peculiar explanation: “I think the earth is of an egg-shaped form, he writes, the ball-shaped yolk is in the middle, white is around it and the shell surrounds everything; the same way the earth is in the centre like the yolk, air is around it like the white and the sky surrounds everything like the shell.
Shirakatsi’s astronomical system is not heliocentric but geocentric.
Accepting the egg-shape of the Earth it was important to explain the issue of earth balance. This question was of great interest since the ancient times and different opinions were made; some people thought that the earth lay on a gigantic elephant, others considered that it lay on a huge whale, on seas, etc. Shirakatsi gives a very original explanation to this question. He finds that it is balanced by two opposite forces and he writes: “The Earth tends to go down with all its weight and the wind tries to raise it up with all of its power. That’s why the earth doesn’t fall down and the wind doesn’t raise it up”.
In his cosmographic work Shirakatsi tells about the Galaxy (the Milky Way) and tries to explain its main point. Criticizing all the legends of his time he gives a scientific explanation concerning that issue. According to him the Galaxy is the same as “the mass of densely possessed and weakly shining stars”.
Shirakatsi absolutely rejects conservative scientists’ points of view. Among them there are church priests who think that the moon has its own light. He finds that the moon doesn’t have its own light and obtains light from the Sun which reflects the light of the ether like a mirror. According to him it is related to the reflection of sunlight and the change of lunar phases. The sun is in the fifth zone of the sky, and the moon is in the 4th one. Therefore, the moon obtains the light from above, and as the sun and the moon are in perpetual motion round the earth at different speed they either approach or move away. During the period when the sun approaches the moon, its light cycle begins to diminish and in case of moving away it begins to enlarge.
Shirakatsi explains high and low tide of the oceans and seas by changes of lunar phases: during the full moon water level in the oceans and seas begins to rise and when diminishing to fall.
In his cosmographic work Shirakatsi discusses also the solar and the lunar eclipses. According to him the solar eclipse occurs when the sun is in the northern hemisphere, and the Moon in the southern, the earth is between them and hiders the light penetration to the Moon then the lunar eclipse occurs.
In the cosmographic work Shirakatsi criticizes Chaldean astrologists who assures that the fate of the people happy and unhappy, kind and unkind, rich and poor depends on the star under which they were born. Shirakatsi considers such scientists' statements nonsense and names them witches.
In his works Shirakatsi also touches upon other issues concerning the natural phenomena: light and sound speed, causes of the rain, snow, thunder, lightning, springs, etc.
One of his valuable works is “Ashkharhatsuyts” (“Geography”), which includes the description of all the countries in the world discovered at that time. That is a great work in the World Geographical and Cartographical literature of that time. “Ashkharhatsuyts” consists of Introduction and two parts. In the introduction Shirakatsi determines the zones and temperature of the Earth defining the points of view existing in the science. In the first part he gives a general description of the Earth and in the second part there is a description of different countries known at that time. In the main part of “Ashkharhatsuyts” is the description of all the countries in the three continents known then: they are Europe, Africa and Asia. Here the author defines the boundaries of each described country, distinguishes the rivers, mountains and towns, etc.
Metrological works of Anania Shirakatsi are also of great interest: “about the length measures” and “about the weight measures”. His metrological works contain the basic measurements and concepts existing in Armenia then. It is notable that in the 7th century Armenia was an important center of Foreign International trade. Probably Armenian merchants needed some information book containing information about different nations, particularly Persian and Byzantine nations. And Shirakatsi as it is known took the responsibility to form measurements and conceptions of his time and conscientiously realized it.
An important source on economic life of historical Armenia is Shirakatsi's “Mghonachap”, where the ways of camel cades, which crossed Armenia in the 6-7th centuries are depicted.
Shirakatsi has also a little text referring to precious stones. He enumerates 33 various precious stones noting the colors and distinguishing characteristics of each.
Some historical evidence having a great value on socio-economic history of Armenia and neighboring countries is given in “Chronology”. It begins with the part including ancient times taken from Movses Khorenatsi's sources. One of the original and important parts of “Chronology” is the chronics of the kings of Sasanyan Persia, which begins with the period when the king Artashes Sasanid ruled and it is over with the king Khosrov, the son of Vormizd. The last part of “Chronology” is chronics of Roman and Byzantine emperors beginning with Julius Ceasar and ending in days of Justinian II (in 681).