(1654-1705). A Swiss mathematician
and son of a prosperous drug merchant.
Jakob went to Geneva in 1676 to work as a tutor, spent two years in France, then in 1681-2 studied in England and the Netherlands. He returned to Basel in 1683 and gave lectures on mechanics (Experimentalphysik). In 1687 he became professor of mathematics at University of Basel (after shafting his brother Johann, the poor bastard). He was the discoverer of the logarithmic spiral, the only curve to follow the pattern of the mollusk shell, and discovered the law of large numbers, which is used for risk management and insurance. Of course, I wasn't a math major, so I'm sure that I'm missing significant things :-)
Jakob was the brother of Johann (1667-1748, inventor of the calculus of variations and discoverer of the Brachistone curve). Johann got the chair in mathematics at Basel following the death of his brother in 1705. He also lived in Jakob's house with Paul Euler (Leonhard's father).