D'ALEMBERT. 435 



Diderot was his most intimate and earliest friend; and 

 he it was who prevailed upon him to join in the conduct 

 of a great literary undertaking, the first French Encyclo- 

 paedia. This work was published at Paris from 1751 

 to 1758; and of these seven volumes D'Alembert and 

 Diderot were the joint editors. D'Alembert also con- 

 tributed many of the best articles, and wrote the cele- 

 brated Preliminary Discourse upon the distribution and 

 the progress of the sciences. The merit of those articles 

 is generally, as might have been expected from such a 

 writer, great in proportion as he exerted himself to 

 elaborate and to finish them. But the best are, as might 

 have been expected, the mathematical. 



The Preliminary Discourse has, in my very humble 

 opinion, and speaking with an unfeigned respect for 

 both its illustrious author and its eminent eulogists, 

 been praised much beyond its merits. The very ground 

 of those panegyrics, that it traces the invention of 

 the sciences and the arts to the necessities and the 

 desires of individual nature, seems to be a satisfac- 

 tory proof how fanciful and indeed how confined the 

 whole plan of the work is. Professor Stewart has most 

 justly remarked ('Dissertation, Encyc. Brit. Introd/) 

 that there is in the Discourse a total confusion of 

 two things, in themselves wholly different and which 

 ought to have been carefully kept distinct the character 

 and circumstances and progress of the individual, and 

 those of the species. It is the scientific advance of the 

 race that the author professes to treat; but he is con- 

 stantly dealing with the unfolding of the faculties in the 

 man. There arises from hence a most shadowy, in- 

 distinct, and vague view of most points discussed. And 



2 F2 



