The book consists of seven chapters. The first chapter is entitled "The theologian-philosopher in the light of time” and presents Tatevatsi's biography, theoretical origins of his philosophical views and methods of thinking. Saint Grigor Tatevatsi (1346-1409) is the most prominent figure of the Armenian medieval theological-philosophical thought, and his theoretical legacy is the apogee of the Armenian medieval thought, which synthesizes the best traditions of both the Armenian and European scholastic thought of the previous centuries. He was the head of the Tatev University (XIV-XV cc), which was a leading scientific and cultural centre of the time. Scholars of Tatev University fought against the unitorian movement (against unification of the Armenian Apostolic and Roman Catholic Churches).