THE LAWS OF MOTION 285 



dance round groups, and groups of groups dance relatively 

 to each other. How, we have next to ask, do two 

 corpuscles dance with regard to each other ? In the first 

 place we must observe that, at least in the case of gross 

 " matter," a corpuscle which is conceived as forming part 

 of the sun must be considered as regulating its dance with 

 due regard to a corpuscle forming part of the earth. We 

 cannot assert that it would not be best to conceive this as 

 really done through a chain of partners, namely, ether- 

 elements intervening between the sun and earth corpuscles, 

 but as we have not yet settled how this chain of partners 

 is to act, we must content ourselves at present by the 

 statement that sun and earth corpuscles do regard each 

 other's presence. But if they can do this at 90 million 

 miles, there is every reason for inferring no breach 

 in continuity and supposing they would also do it 

 at 90 billion miles. We note, however, at once that it 

 is necessary to conceive a particle at the surface of the 

 earth paying more attention in its dance to an earth 

 particle than to a sun particle, and again the phenomenon 

 of cohesion tells us that two adjacent particles of the 

 same piece of substance pay more heed to each other than 

 particles of different pieces. Hence we conclude that : 

 (i) in general terms corpuscles must be conceived as 

 moving with greater regard to their immediate partners in 

 the dance than to their near neighbours, and with greater 

 regard to near neighbours than to still more distant 

 corpuscles ; but (2) there is no limit to the distance at 

 which we conceive corpuscles can influence each other's 

 motion. This influence may, however, be so small that 

 even when summed for the bodies that we construct from 

 corpuscles, there is no perceptual equivalent to be found 

 for it by aid of any instrument at our disposal. We can 

 now state a first general law of motion : — 



Every corpuscle in the conceptual model of the universe 



must be conceived as moving with due regard to the presence 



' of every other corpuscle, although for very distant corpuscles 



the regard paid is extremely small as compared zuith that 



paid to immediate fieighbours. 



