248 THE GRAMMAR OF SCIENCE 



intelligence, we feel an uncomfortable sense of the meta- 

 physician smiling somewhere round the corner. If our 

 leading scientists either fail to tell us what matter is, or 

 even go as far as to assert that we are probably incapable 

 of knowing, it is surely time to question whether this 

 fetish of the metaphysicians need be preserved in the 

 temple of science. 



^ ^.—Does Matter occupy Space ? 



But to return to Professor Tait ; he has called his book 

 The Properties of Matter, and this the reader will say 

 means something, and something very definite. Now, 

 for the purposes of classifying our sense-impressions, it is 

 undoubtedly useful to term particular groups of them 

 which have certain distinguishing characteristics " material 

 sense-impressions," and these material sense-impressions 

 are what Professor Tait deals with under the properties 

 of matter. It is Professor Tait, the unconscious meta- 

 physician, who groups this class of sense - impressions 

 together and supposes them to flow as properties from 

 something beyond the sphere of perception, namely, 

 matter.^ As a working definition of matter. Professor 

 Tait considers that we may say : " Matter is whatever 

 can occupy space!' Now this definition will lead us to a 

 number of ideas which it is instructive to follow up. In 

 the first place, is it perceptual or conceptual space to 

 which the definition applies.? If the latter, then matter 

 must be a geometrical form — a result which we think our 

 author does not intend. We think it more probable that 

 Professor Tait looks upon space as itself objective, 

 although he avoids any definite statement on this really 

 important issue (see his p. 47). From the standpoint of 

 our present volume, however, space is the mode by which 



1 The unconscious metaphysics of Professor Tait occur on nearly every 

 page of his treatment of the fundamental concepts of physical science. Thus 

 he asserts the " objectivity of matter," while force is not objective, we are 

 told, but subjective. Notwithstanding this assertion, "matter is, as it were, 

 the plaything of force. " How this nothing, this "mere phantom suggestion 

 of our muscular sense," this force, can have an objective plaything it would 

 puzzle a metaphysician to explain. 



