Blaise Pascal

Inventor of the Pascaline, a mechanical calculator capable of addition and subtraction, Pascal built twenty of these machines over the following ten years after constructing the first in 1642 following three years of effort and 50 prototypes.

Pascal was a mathematician of the first order. He helped create two major new areas of research. He wrote a significant treatise on the subject of projective geometry at the age of sixteen, and later corresponded with Pierre de Fermat on probability theory, strongly influencing the development of modern economics and social science.

Following Galileo and Torricelli, in 1646 Pascal refuted Aristotle's followers who insisted that nature abhors a vacuum. His results caused many disputes before being accepted.