2i 6 Unsatisfactoriness of Berkeleyanism. CHAP. 



refuse to form any opinion on the subject, and confine 

 ourselves to stating the mere fact that we know 

 the external world as consisting only of " permanent 

 possibilities of sensation, ".still it makes itself known 

 to us as external ; external, that is, to our conscious- 

 ness and our will. 



I may remark here, though it is a digression from 

 the main argument, that although the progress of 

 physical science, which has extended our knowledge 

 of the material world so marvellously beyond mere 

 sensible perception, tends to merge the idea of matter 

 in that of force, yet it gives no support to that denial 

 of the existence of material substance, which Mill, 

 and, I believe, other agnostics, have adopted from 

 Berkeley. Science reveals an entire world of realities 

 which are not objects of sensible perception ; such as the 

 waves of light, the vibrations of heat, the molecular 

 tensions which constitute magnetism and electricity, 

 and the atomic structure of matter : these are as real 

 as waves in water or stratification in rocks, yet, not 

 being actual or possible objects of perception, their 

 reality seems to be denied by the Berkeleyan theory, 

 which teaches that things exist only as they are per- 

 ceived. 1 And there is also this kindred difficulty; 

 If it is true that material things exist only as they 

 are perceived, what was there to constitute the being 

 of the world of matter when nothing had as yet been 

 created except the primaeval nebula, and no sentient 

 or thinking being had been called into existence to 

 1 As Berkeley tersely puts it, their esse is percipi. 



