68 EXAMINATIONOF 



mony; that the objeds we apprehend as having 

 a real exiftence, are thofe which are invariably 

 prefented to us in the fame manner ; that the 

 mode in which they prefent themfelves has no 

 dependence upon our will or inclination ; that, 

 of courfe, our ideas, inftead of being the caufes 

 of things, are only particular effedls, which be- 

 come lefs fimilar to the objeds themfelves, in 

 proportion as they are rendered more general ; 

 and, laftly, that mental abftradions are only ne- 

 gative beings, which derive their intelledual ex- 

 iftence from the faculty we poiTefs of confider- 

 ing objects, without regarding their fenfible qua- 

 lities ? 



Is it not, therefore, apparent, that abftrad i- 

 deas can never be the principles of exiftence, or 

 of real knowledge ? On the contrary, all our 

 knowledge is derived from comparing and ar- 

 ranging the refults of our fenfations. Thefe re- 

 fuks are known by the appellation oi experience^ 

 the only fource of genuine fcience. The em- 

 ployment of any other principle is an abufe; and 

 every edifice founded upon abftradt ideas, is a 

 temple ereded to Error. 



In philofophy, error has a more extenfive in- 

 fluence than in morals. A thing may be falfe 

 in morals folely becaufe it is mifreprel'ented. But 

 falfehood in metaphyfics confifts not in mifre- 

 prefentition alone, but intakingfor granted what 

 has no exiftence at all. It is into this moft per- 

 nicious jpecies of error that the Platonifts and 



the 



