discrete mathematics

...Заколюченные параллели
Преподали нам славный урок:
Не делить с подонками хлеба,
Перед властью не падать ниц,
И не верить ни в чистое небо,
Ни в улыбки сиятельных лиц....

With scoundrels, never break your bread, 
Before no power bow your head, 
And put no trust in shifting sand, 
Nor in the smiles of high and grand.

by poet Alexander Galich

The equations and theorems were sand scribbles written in the beach by Anne Schilling’s father, a physicist who worked at the European Organization for Nuclear Research (CERN). As her father wrote, Schilling absorbed as much of the information as possible before the Atlantic Ocean’s waves washed the mathematics away, the seafoam acting like an eraser on a blackboard.