Michał Kalecki was born on 22 June 1899 in Łódź, Congress Poland, then part of the Russian Empire. Information about his early years is very sparse, part of it being lost during the Nazi occupation, but he grew up in a major labor-turbulent industrial center, which affected his future views. In 1917 Kalecki enrolled at the Warsaw Polytechnic to study civil engineering. He was a very able student and formalized a generalization of Pascal's theorem, concerning a hexagon drawn within a second-degree curve: Kalecki generalized it for a polygon of 2n sides.