The idea of a tipping point came into common parlance along with chaos theory, the hundredth monkey, and black swans during the computer age. But it was less than a hundred years ago the idea had sketchy scientific support, and was regarded with skepticism.
In 1920, in a world recovering from a global flu pandemic, a German physicist named Wilhelm Lenz set out to understand why heating a magnet past a certain temperature causes it to suddenly lose its attractive power, as Pierre Curie had discovered 25 years earlier. Lenz thought up a simple model, in which each atom in a crystal is a tiny magnet, and its energy depends on how it is oriented compared to adjacent atoms in the crystal. He tasked his graduate student, Ernst Ising, with working out the details.