ENCYCLOPEDIE Ml^THODIQUE. 44?1 



given. The object of the problem is to shew to a gambler, by an 

 example, that if a wager is really unfavourable to him he suffers 

 still more by increasing his stake while the same proportion is 

 maintained between his stake and that of his adversary. 



821. Pages 134 — 149 relate to the evaluation of probability 

 from experience or observation. If an event has happened m 



times and failed n times the book directs us to take — - — as its 



m-\- n 



chance in a single trial. 



822. Pages 150 — 164 relate to the evaluation of probability 

 from testimony. Bicquilley adopts the method which we have 

 exhibited in Art. 91. Another of his peculiarities is the following. 

 Suppose from our own experience, independent of testimony, we 

 assign the probability P to an event, and suppose that a witness 

 whose probability is 2^ offers his evidence to the event, Bicquilley 

 takes for the resulting probability P+ (1 — P) Pp, and not as we 

 might have expected from him P + (1 — P) ^. He says that the 

 reliance which we place on a witness is proportional to our own 

 previous estimate of the probability of the event to which he 

 testifies. 



823. We will now notice the matter bearing on our subject 

 which is contained in the Encyclopedie Methodique; the mathema- 

 tical portion of this work forms three quarto volumes which are 

 dated respectively 1784, 1785, 1789. 



Absent This article is partly due to Condorcet : he applies 

 the Theory of Probability to determine when a man has been ab- 

 sent long enough to justify the division of his property among his 

 heirs, and also to determine the portions which ought to be assigned 

 to the different claimants. 



Assurances. This article contains nothing remarkable. 



ProhoMlite. The article from the original Encyclopedie is re- 

 peated : see Art. 467. This is followed by another article under 

 the same title, which professes to give the general principles of 

 the subject. The article has not Condorcet's signature formally 

 attached to it ; but its last sentence shews that he was the author. 

 It may be described as an outline of Condorcet's own writings on 



