Kiyosi Itô

, 7 September 1915 – 10 November 2008}} was a Japanese mathematician who made fundamental contributions to probability theory, in particular, the theory of stochastic processes. He invented the concept of stochastic integral and stochastic differential equation, and is known as the founder of so-called Itô calculus. He also pioneered the connections between stochastic calculus and differential geometry, known as stochastic differential geometry. He was invited for the International Congress of Mathematicians in Stockholm in 1962. So much were Itô's results useful to financial mathematics that he was sometimes called "the most famous Japanese in Wall Street".

Itô was a member of the faculty at University of Kyoto for most of his career and eventually became the director of their Research Institute for Mathematical Sciences. But he also spent multi-year stints at several foreign institutions, the longest of which took place at Cornell University. Provided by Wikipedia