The basic principle had been discovered much earlier. Vilfredo Pareto (1848–1923), an Italian polymath, noticed its applicability to wealth distribution in the early twentieth century, and it appears true for every society ever studied, regardless of governmental form. It also applies to the population of cities (a very small number have almost all the people), the mass of heavenly bodies (a very small number hoard all the matter), and the frequency of words in a language (90 percent of communication occurs using just 500 words), among many other things.
