io ] [BookL 



CHAP. III. 



OF THE EXTENSION, SOLIDITY, AND 

 DIVISIBILITY OF MATTER. 



Extenjion the only Quality ejjential to Matter. Solidity, ivbat. Infi- 

 nite Divijibility. A;iimalculee imperceptible to our Senj'cs. Extreme 

 Rarity of Light. Newtonian Paradox. 



T7X1 i ENSIONis a property fo obvioufly eiTential 

 ^-' to whatever occupies fpace, that it is accounted 

 the firft and moft indifpenfable attribute common to 

 all matter. It is indeed the only property which we 

 can pofitively fay is dfential ta matter, fince all the 

 others that have been fpecified are fo be underftood 

 with fome limitation, and do not appear to be common 

 to all Bodies whatever. 



We have no idea of Jolidity^ but that which is fur- 

 nifhed by the refiftance which we find in a body to the 

 entrance of any other body into the place it occupies 

 till it has left it *. This property of matter therefore 

 neceffarily includes neither impenetrability nor hard- 

 nefsj the amazing porofity of bodies militates againft 

 the one idea, and the almoft infinite divifibility of mat- 

 ter againft the other. Indeed nothing can be more 

 inconfiftent than to fpeak of the abfolute folidity and 

 impenetrability of the ultimate particles of matter, and 

 afterwards to enlarge upon its infinite divisibility; both 

 of thefe are fafls which are totally undetermined by 

 experiment or obfervation ; and when we fpeak of the 



* See Mr. Locke's EflJ on Hum, Under. B. ii. c. 4. 



actual 



