Joseph Louis Bertrand was born in Paris on March 11, 1822. Bertrand held teaching positions variously at Ecole Polytechnique and Collège de France. Bertrand made significant contributions in number theory, differential geometry, probability and statistics. To students of probability, he is best known for the famous paradox that bears his name, which appeared in his book Calcul des Probabilitiés, (Calculus of Probabilities) published in 1888. In statistics, Bertrand worked on the theory of errors and the method of least squares, as formulated by Carl Friedrich Gauss.
Bertrand was appointed secretary of the Paris Academy of Sciences in 1874 and was elected a Fellow of the Royal Society in 1875. He died on April 5, 1900 in Paris.