272 d'alembert. 



de Philosophie, Vol. v. I have never seen the original edition of 

 this work ; but I have no doubt that the remarks in the Melanges 

 de Philosopliie were those which are reprinted in the first volume 

 of the collected edition of the literary and philosophical works of 

 D'Alembert, in 5 Vols. 8vo, Paris, 1821. According to the cita- 

 tions of some writers on the subject I conclude that these remarks 

 also occur in the fourth volume of the edition of the literary and 

 philosophical works in 18 Vols. 8vo, Paris, 1805. 



490. In the first volume of the edition of 1821 there are two 

 essays, one on the general subject of Probabilities, and the other on 

 Inoculation. 



The first essay is entitled Doutes et questions sur le Calcul des 

 Prohahilites. These occupy pages 451 — 466 ; the pages being 

 closely printed. 



D'Alembert commences thus : 



On se plaint assez communement que les formules des matli^ma- 

 ticiens, appliquees aux objets de la nature, ne se trouvent que trop 

 en defaut. Personne neanmoins n'avait encore apergu ou cru aper- 

 cevoir cet inconvenient dans le calcul des prohahilites. J'ai os6 le 

 premier proposer des doutes sur quelques principes qui servent de base 

 ii ce calcul. De grands geometres ont juge ces doutes dignes d' attention; 

 d'autres grands geometres les ont trouves ahsurdes; car pourquoi adou- 

 cirais-je les termes dont ils se sont servis ? La question est de savoir 

 s'ils ont eu tort de les employer, et en ce cas ils auraient doublement 

 tort. Leur decision, qu'ils n'ont pas juge a propos de motiver, a en- 

 courage des mathematiciens mediocres, qui se sont hates d'ecrire sur ce 

 sujet, et de m'attaquer sans m'entendre. Je vais tacher de m'expliquer 

 si clairement, que presque tous mes lecteurs seront a portee de me 

 jager. 



491. The essay which we are now considering may be described 



in general as consisting of the matter in the second volume 



of the Opuscides divested of mathematical formulae and so adapted 



to readers less versed in mathematics. The objections against 



the ordinary theory are urged perhaps with somewhat less con- 



2 

 fidence ; and the particular case in which - was proposed in- 



3 . 



stead of 7 ^s the result in an elementary question does not appear. 



But the other errors are all retained. 



