Bruno de Finetti was born on 13 June 1906 in Innsbruck, Austria. He studied mathematics at the Polytechnic University of Milan, graduating with a PhD degree in 1927. After graduation, de-Finetti worked as a statistician at the National Institute of Statistics in Rome and as an actuary for an insurance company. His academic career took him from Padua University to the University of Trieste and then to Sapienza University in Rome.
De Finetti was an ardent advocate for subjective probability. Mathematically, he is best known work on exchangeable sequences of random variables, and in particular for the theorem that now bears his name: Every exchangeable sequence of indicator random variables can be obtained by randomizing the success parameter in a sequence of Bernoulli trials. De Finetti's theorem has since been greatly generalized. He also worked on infinitely divisible distributions and on applications to genetics. De Finetti was a prolific researcher, publishing papers in the foundations of mathematics, measure theory, geometry, and computer science in addition to probability and stochastic processes. His best known book, Theory of Probability was published in 1970 and translated into English in 1975.
In addition to mathematics, de Finetti held passionate views on political and economic issues. He ran for political office on several occasions and was at one point arrested for antimilitarist activities. Bruno de Finetti died on 20 July 1985 in Rome.