428 ANTIENT METAPHYSICS. Book V. 



In fiich a condition, therefore, we are able to diftinguifh betwixt 

 illuiion and reality, our dreaming, and our waking thoughts, and 

 pronounce, with certainty, that the perceptions of fenfe, when we 

 are awake, are produced by objeds without us ; whereas, when 

 we are afleep, they are all from within, and the work of the phantafia 

 only. 



Nor are there wanting many examples of men, while awake, being 

 in [o imperfedl a Hate of mind : For madmen, and perfons in a de- 

 lirium, haN^e no recolledion of their paft adions, and a£l- as if the 

 phantafms of imagination were realities. Now, I confider a dream as 

 a kind of fhort madnefs or delirium, of which we recover when we 

 awake ; and I think it as ridiculous to judge of truth and nature by 

 what appears to the madman, as by what appears to the dreaming 

 man. 



Nor fliould it move us, that what we fee in our dreams very often 

 afFe(^s us as much, and fometimes more, than what we fee when we 

 are awake : For the fictitious fcene we fee upon the ftage, or the re- 

 prefentations of the magic lanthorn, affedt us very much ; But there 

 is this difference betwixt thefe reprefentations, and what is prefented 

 to us in dreams, that we know the former to be mere illufion ; 

 whereas we do not know the latter to be fo, but take them for reali- 

 ties, unlefs when we are, as I obferved before, upon the confines of 

 fleeping and waking, and have the confcioufnefs of our waking 

 thoughts j ined with our dreams. 



Thus, I think, I have proved, that the fcene which nature prefents 

 to us is not an illufion, but confifts of real objeds, which, by impulfe 

 upon our organs of I'enle, produce all our fenfations ; and, as noth ng 

 can impel, or be impelled, that is not folid and extended, and, as every 



thing 



