Does Matter Exist? 



perties. All matter has mass, is heavy and is 

 inert. 1 It is a remarkable fact that scientists 

 belonging to different centuries and having such 

 diverse training should unite in this common 

 affirmative. If any object, such as a piece of 

 chalk, is put in one of the scales of a balance, a 

 certain weight, say 20 grammes, placed in the 

 opposite scale will balance it; hence the infer- 

 ence that the piece of chalk contains as much 

 matter as the 20 grammes of copper, though it 

 may not be the same kind of matter, and the 

 mass of the chalk is said to be 20 grammes. 

 Whether it be gold, platinum or hydrogen, the 

 lightest of gases, it can be put in the balance and 

 the quantity of matter it contains measured. 

 Here we have therefore a property common to all 

 kinds of matter, the possession of mass, and 

 this property is characteristic because if the 

 operation is repeated at the pole, at the equator, 



1 It is interesting to remark that regarding this question of 

 the essence of matter the ideas of scientists and metaphysicians 

 have evolved on parallel lines. The hypotheses of Descartes, 

 which proclaim extension to be the fundamental property of 

 bodies, have given place to Leibnitz's conception of a world 

 based on the existence of force ; now the notion of force is as 

 closely associated with the notion of mass and inertia as the 

 idea of extension is with the idea of impenetrability. 



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