212 HUME ix 



ably have replied, that, if morality has no better 

 foundation than an assumption, it is not likely to 

 bear much strain; and, if it has a better foun- 

 dation, the assumption rather weakens than 

 strengthens it. 



As has been already said, Hume is not content 

 with denying that we know anything about the 

 existence or the nature of the soul; but he carries 

 the war into the enemy's camp, and accuses those 

 who affirm the immateriality, simplicity, and 

 indivisibility of the thinking substance of atheism 

 and Spinozism, which are assumed to be con- 

 vertible terms. 



The method of attack is ingenious. Observa- 

 tion appears to acquaint us with two different sys- 

 tems of beings, and both Spinoza and orthodox 

 philosophers agree, that the necessary substratum 

 of each of these is a substance, in which the 

 phenomena adhere, or of which they are attributes 

 or modes. 



" I observe first the universe of objects or of body ; the 

 sun, moon, and stars ; the earth, seas, plants, animals, men, 

 ships, houses, and other productions either of art or of na- 

 ture. Here Spinoza appears, and tells me that these are 

 only modifications and that the subject in which they in- 

 here is simple, uncompounded and indivisible. After this 

 I consider the other system of beings, viz., the universe of 

 thought, or my impressions and ideas. Then I observe 

 another sun, moon, and stars ; an earth and seas, covered 

 and inhabited by plants and animals, towns, houses, moun- 

 tains, rivers ; and, in short, everything I can discover or 

 conceive in the first system. Upon my inquiring concern- 



