164 



CHAP. II. 



SECT. I. 

 Of the pure Intellect and its Operations, 



L AVING hitherto considered the ideas of sensa- 

 tion as the only materials the mind of man has to 

 work upon, I come to treat of the mind itself, or the 

 Pure Intellect. I do not mean by this, the immate- 

 rial part of us, nor yet the most refined and exqui* 

 site parts of the body, which are immediately sub- 

 servient to its nobler operations : but both of these 

 operating together in essential union. 



Our present knowledge is gradually performed, 

 by the concurrent motion of some bodily part within 

 us ; which is the cause of that weariness we feel, after 

 long-continued thinking. We should never be tired 

 with this, if the pure spirit could reason indepen- 

 dently of all material organs. But experience shews 

 us, the case is otherwise : we find it a labour to the 

 brain, and feel ourselves as much wearied with in- 

 tense thought, as with hard bodily labour : having 

 premised this of them in general, I proceed to consi* 



