EN
The subject of the article is a mathematical approach for understanding the Trinity. The method consists of identification of provenance of the three persons with multiplication. The author analyses the origin of the mentioned method in the Augustine’s works, its reception and development in the works of such XII century philosophers as Achard of Saint-Victor and Thierry of Chartres. Their teachings are treated from the point of view of Neo-Platonism that stimulates to pose the question of conformity of those theories to the official doctrine of Catholic Church.