inventor, philosopher, and writer. A child prodigy, he laid the foundation work for today’s modern theory of probabilities and formulated what came to be known as Pascal’s principle of pressure. The Frenchman also corresponded with Pierre de Fermat on probability theory, strongly influencing the development of modern economics. He is also one of the first two inventors of the mechanical calculator, having started pioneering work on calculating machines called Pascal's calculators or Pascalines.