**Jules Bienaymé** worked on statistics and probability.

- However, he did not use the name, always using the name Jules.
- Jules attended the Lycée impérial at Bruges and the city had happy memories for him.
- After taking part in the defence of Paris in 1814, Jules Bienaymé entered the École Polytechnique in the following year.
- In 1819 Bienaymé, wanting to make a career in science rather than administration, became a lecturer in mathematics at the military academy of St Cyr.
- There do seem to be more reasons why he left and one seems related to Siméon Denis Poisson, who had chosen him for the post, for from that time on Bienaymé became openly hostile to him.
- They had long known each other for the Bienaymé and Harmand families had shared the same house in Paris for a while.
- In 1852 Bienaymé was elected to the Paris Academy of Sciences and for the next 23 years he was the referee for the statistics prize.
- Bienaymé only published 23 articles during his life and half of these were published in obscure places such as the L'Institut.
- Bienaymé supported Laplace on this issue.
- Bienaymé supported Laplace in general since it was Laplace's "Théorie analytique des probabilités" Ⓣ(Analytic theory of probabilities) (1812) that was the biggest influence on Bienaymé's scientific thinking throughout his life.
- An excellent linguist, Bienaymé translated Pafnuty Chebyshev's work from Russian into French.
- Bienaymé was a friend of Chebyshev (they first met in October 1852), and also of other important mathematicians such as Adolphe Quetelet, Antoine Cournot and Gabriel Lamé.
- Quetelet and Bienaymé were born in the same year and corresponded regularly between 1846 (the year in which they first met) and 1871.
- On the other side, there were a number of mathematicians who Bienaymé seems particularly keen to criticise, such as Augustin-Louis Cauchy, Siméon Poisson and Joseph Bertrand.
- Bienaymé was quite wrong in his criticism of Poisson but in general he was years ahead of his time in the depth of his statistical ideas.
- Bienaymé published the Bienaymé-Chebyshev inequality, which was used to give a very simple and precise demonstration of the generalised law of large numbers, in his important paper "Considérations à l'appui de la découverte de Laplace sur la loi de probabilité dans la méthode des moindres carrés" Ⓣ(Considerations to support the discovery of Laplace on the probability distribution in the least squares method) (1853).
- Possibly the Inequality was regarded by Bienaymé as a minor result compared with his main themes of linear least squares and Laplacian defence.

Born 28 August 1796, Paris, France. Died 19 October 1878, Paris, France.

View full biography at MacTutor

**O’Connor, John J; Robertson, Edmund F**: MacTutor History of Mathematics Archive