Johann Bernoulli

Johann Bernoulli, who lived from 1667 to 1748, was a Swiss mathematician and one of the prominent mathematicians of the Bernoulli family, known for his contributions to infinitesimal calculus and for educating the young Leonhard Euler. Born in Basel, the son of an apothecary, he turned away from the family spice trade, studied medicine at the University of Basel and took his degree in 1690 with a dissertation reviewed by Gottfried Leibniz, while learning calculus on the side from his older brother Jacob. He became professor of mathematics at the University of Groningen in 1694 and returned to Basel in 1705 to take over his late brother's chair. A loyal student of Leibniz, he defended him in the calculus priority dispute with Newton and championed Descartes' vortex theory over Newton's gravitation. His brachistochrone challenge of 1696 provoked a bitter rivalry with Jacob, and he tutored the Marquis de l'Hopital, whose famous calculus textbook drew heavily on his work.