SECT. III. 6. 4- THE RETINA. i 9 



flump with a fimilar degree or kind of pain, the ideas of the 

 fhape, place, or folidity of the loft limb, return by aiTociation ; 

 as thefe ideas beWhg to the organs of fight and touch, on 

 which they were fir ft excited. 



4. If you wonder what organs of fenfe can be excited into 

 motion, when you call up the ideas of wifdom or benevolence, 

 which Mr. Locke has termed abftracled ideas ; I afk you, by 

 what organs of fenfe you fir ft became acquainted with thefe 

 ideas ? And the anfwer will be reciprocal ; for it is certain that 

 all our ideas were originally acquired by our organs of fenfe ; 

 for whatever excites our perception muft be external to the or- 

 gan that perceives it, and we have no other inlets to knowledge 

 but by our perceptions : as will be further explained in Sedlion 

 XIV. and XV. on the Productions and ClafTes of ideas. 



VII. If our recollection or imagination be not a repetition of 

 animal movements, I afk, in my turn, What is it ? You tell me 

 it confifts of images or pictures of things. Where is this ex- 

 tenfive canvas hung up ? or where are the numerous receptacles 

 in which thole are depofited ? or to what elfe in the animal 

 iyftem have they any iimilitude ? 



That pleafing picture of objects, reprefented in miniature on 

 the retina of the eye, feems to have given rife to this illufive or- 

 atory ! It was forgot that this reprefentation belongs rather to 

 the laws of light, then to thofe of life ; and may with equal ele- 

 gance be feen in the camera obfcura as in the eye ; and that the 

 pifture vanidies for ever, when the object is with drawn. 



SECT. 



