The book focuses on the role of mathematics in man's knowledge of the outside world. The author describes the achievements of modern mathematics using as an example creative biographies of three outstanding Russian mathematicians of the XX century as A. N. Kolmogorov, S. L. Sobolev and A. N. Tikhonov.
The book will be interesting for students, teachers and tutors of mathematics and, as well as for everybody interested in this science.