The distant year 1923. In one Moscow school, a boy stopped attending classes. Doesn't go for a week, two ...
Lyova did not have a phone, and classmates, on the advice of the teacher, decided to go to his house. Levin's mother opened the door. Her face was very sad. The guys greeted and asked timidly: "Why doesn't Lyova go to school?" Mom sadly replied: "He will no longer study with you. He underwent surgery. It was unsuccessful. Lyova is blind and cannot walk himself ..."
The guys were silent, looked at each other, and then one of them suggested: "And we will take him to school in turn."
- And see off home.
- And we will help to do the lessons, - classmates chirped, interrupting each other.
Tears welled up in my mother's eyes. She led her friends into the room. A little later, feeling the way with his hand, Lyova came out to them with a bandage over his eyes. The guys froze. Only now did they really understand what a misfortune happened to their friend. Leva said with difficulty: "Hello." And then from all sides rained down: - Tomorrow I will come for you and take you to school. - And I'll tell you that we went through algebra. - And I’m from history.
Lyova did not know whom to listen to, and only nodded in confusion. Tears rolled down my mother's face. After leaving, the guys made a plan - who comes in when, who explains what subjects, who will walk with Lyova and take him to school. At school, the boy, who was sitting with Lyova at the same desk, quietly told him during the lesson what the teacher was writing on the blackboard. And how the class froze when Leva answered! How everyone rejoiced at his fives, even more than their own! Lev studied perfectly. The whole class also began to study better. In order to explain a lesson to a friend in trouble, you need to know it yourself. And the guys tried. Moreover, in the winter they began to take Lyova to the skating rink. The boy was very fond of classical music, and classmates went with him to symphony concerts ...
Lev graduated from the school with a gold medal, then entered the institute. And there were friends who became his eyes. After the institute, Loew continued to study and, in the end, became a world famous mathematician, academician Pontryagin. Do not count people who have received their sight for good.
Lev Semyonovich Pontryagin (1908-1988) - Soviet mathematician, one of the greatest mathematicians of the 20th century, academician of the USSR Academy of Sciences, who lost his sight at the age of 14. He made significant contributions to algebraic and differential topology, oscillation theory, calculus of variations, and control theory. In control theory, Pontryagin is the creator of the mathematical theory of optimal processes, which is based on the so-called. the Pontryagin maximum principle; has fundamental results on differential games. The works of the Pontryagin school had a great influence on the development of control theory and the calculus of variations all over the world.