CHAPTER VII. 



JAMES BERNOULLI. 



92. We now propose to give an account of the Ars Conjec- 

 tandi of James Bernoulli. 



James Bernoulli is the first member of the celebrated family 

 of this name who is associated with the history of Mathematics. 

 He was born 27th December, 1654, and died 16th August, 1705. 

 For a most interesting and valuable account of the whole family 

 we may refer to the essay entitled Die Mathematiker Bernoulli. . . 

 von Frof. Dr. Peter Merian, Basel, 1860. 



93. Leibnitz states that at his request James Bernoulli studied 

 the subject. Feu Mr. Bernoulli a cultive cette mati^re sur mes 

 exhortations; Leibnitii Opera Omnia, ed. Dutens, Vol. Vl. part 1, 

 page 217. But this statement is not confirmed by the correspond- 

 ence between Leibnitz and James Bernoulli, to which we have 

 already referred in Art. 59. It appears from this correspondence 

 that James Bernoulli had nearly completed his work before he 

 was aware that Leibnitz had heard any thing about it. Leibnitz 

 says, page 71, 



Audio a Te doctrinam de aestimandis probabilitatibus (quam ego 

 magni facio) non parum esse excultam. Vellem aliqiiis varia ludendi 

 genera (in quibus pulchra hujus doctrinae specimina) mathematice trac- 

 taret. Id simul amoenum et utile foret nee Te aut quocunque gra- 

 ^issimo Mathematico indignum. 



James Bernoulli in reply says, page 77, 



Scire libenter velim, Amplissime Vir, a quo habeas, quod Doctrina 

 de probabilitatibus aestimandis a me excolatur. Yerum est me a plu- 



