Invito patre sidera verso. (Against my father’s will, I study the stars.)

— Jakob Bernoulli's motto

James Bernoulli (1655–1705), whom the Swiss call Jakob and the French Jacques, was the first mathematician of a family that gave Europe eight of them in three generations. His father wanted a pastor; he studied theology to obey and mathematics in secret. He learned Leibniz’s calculus practically on his own, taught it to his younger brother Johann, and then spent years quarrelling with him in public.

He was the first to use the word integral in a paper, found the number $e$ while doing interest calculations, showed that the sum $1+\frac12+\frac13+\cdots$ has no end and asked Europe for help in adding up the reciprocals of the squares, the problem that Euler would solve. His most important work, the Ars conjectandi, only came out eight years after his death. It contains the first proof that the frequency of an event, over many trials, approaches its probability.

In this track we tell the life of James Bernoulli and redo, with all the calculations shown, six of his discoveries.

James (Jakob) Bernoulli

Who he was

James (Jakob) Bernoulli

Nascimento
6 January 1655, Basel
Morte
16 August 1705, Basel
Origem
Switzerland
Áreas
Probability, series, calculus and the geometry of curves

Reading guide

Biography

Discovery and proof

Legacy and sources