On April 25, 1903, Soviet mathematician Andrey Nikolaevich Kolmogorov was born. He was one of the most important mathematicians of the 20th century, who advanced various scientific fields, among them probability theory, topology, intuitionistic logic, turbulence, classical mechanics, algorithmic information theory and computational complexity.
On April 17, 1761, English mathematician and Presbyterian minister Thomas Bayes passed away. He is best known as name giver of the Bayes' theorem, of which he had developed a special case. It expresses (in the Bayesian interpretation) how a subjective degree of belief should rationally change to account for evidence, and finds application in in fields including science, engineering, economics (particularly microeconomics), game theory, medicine and law.