242 General Observations. Bk. iii. 



taken place, which has produced no eft'ect upon 

 agriculture, and has merely been followed by an 

 increase of diseases ; but perhaps there is no in- 

 stance, where a permanent increase of agriculture 

 has not effected a permanent increase of popula- 

 tion somewhere or other. Consequently, agri- 

 culture may with more propriety be termed the 

 efficient cause of population, than population of 

 agriculture ; * though they certainly re-act upon 

 each other, and are mutually necessary to each 

 other's support. This indeed seems to be the 

 hinge on which the subject turns ; and all the pre- 

 judices respecting population have, perhaps, arisen 

 from a mistake about the order of precedence. 



The author of L'Ami des Hommes, in a chapter 

 on the effects of a decay of agriculture upon po- 

 pulation, acknowledges that he had fallen into a 

 fundamental error in considering population as the 

 source of revenue ; and that he was afterwards 

 fully convinced that revenue was the source of 

 populalion.-j" From a want of attention to this 

 most important distinction, statesmen, in pursuit 

 of the desirable object of population, have been 

 led to encourage early marriages, to reward the 

 fathers of families, and to disgrace celibacy ; but 



* Sir James Steuart explains himself afterwards by saying, that 

 he means principally the multiplication of those persons, who have 

 some valuable consideration to give for the products of agriculture : 

 but this is evidently not mere increase of population, and such an 

 explanation seems to admit the incorrectness of the general propo- 

 sition. 



t Tom. viii. p. 84, 12mo. 9 vols. 1762. 



