"A man is an animal whose words are measured."
You can find this phrase written in Svyatoslav's Collection, one of the longest books from Ancient Russian. The multi-page, handwritten, parchment volume on the subject of human nature was finished in 1073 and was meant to serve as a state treasure. However, judging by its content it was also written to be understood by the common inhabitants of Ancient Rus. Work on the volume began during the reign of Izyaslav Yaroslavovich. It was a troubled time, marked by constant fratricidal war and violent executions, and Izyaslav was eventually sent into exile. For several years, he wandered throughout the neighboring countries of Poland and Germany. When completed, the Collection was named after Izyaslav's younger brother, who had seized power.
Today, the manuscript is the second oldest book that remains from Ancient Rus. It was a copy of the Bulgarian King Simeon I's "Code of Laws" which was a translation of a Greek text. In general, the book was a guide to life complete with pictures.
Much of the text focuses on the Bible and what it means to lead a Christian life. It primarily references authoritative Byzantine theologians such as Basil of Caesarea. However, the book also contains other types of information: astronomy and astrology (drawings with zodiac signs), mathematics, physics, zoology, botany, grammar, ethics, logic and even ideas from the emerging Christian (not Aristotelian) philosophy of the day. In this text, you can find information on what makes a wife "good" or "bad" and lists of books that should be read, as well as those that are "false" and should be ignored. It also describes how the soul, like the body, is essential (while wisdom is merely a coincidence) and describes the result of what happens to a person when he loses his individuality.