The paper deals with the start of the researches in the field of symbolic logic at the department of logic of philosophical faculty of Leningrad university. It is pointed that the researches by proper staff and aspirants of the department of logic were outbreak exactly in 1956 as a result of sharp changes. The work of I.N.Brodsky on the course of symbolic logic is shortly outlined. The principal attention is paid to the examination and analysis of the first theses, defend by A.N.Knigin at the department of logic in 1957, which was an effort to comprehend the content and aims of mathematical logic in the framework of materialist philosophy and traditional logic. Its structure, main content and principal conclusions are depicted. The attention is paid to place of the theses in the historical context of the philosophical logic investigation in the USSR, namely that it was hardly not first in the country thesis in mathematical logic defend by philosopher.