Although he came to mathematics relatively late in life, Nikolai Nikolaievich Lusin made significant contributions in the area of , measure theory, and set . In fact, he is considered one of the founders of the famous Moscow school of function theory, which had its heyday in the 1920s. Lusin was also known in academic circles for his brilliant lectures and unconventional approach to solving problems.

Lusin was the only son of a trade official and his wife, born in Irkutsk on December 9, 1883. In about 1894 the family moved to Tomsk so the boy could attend the city's excellent gymnasium (a classical college-preparatory school). However, the move was something of a disaster, since Lusin began to do so poorly in mathematics that his father had to hire a tutor. It soon became apparent that Lusin was gifted in mathematics, but that he had difficulty solving problems using the prescribed methods. Instead...