274 



THE CAUSE OF THE 



of the particles of living matter which results in actual 

 movement. Is it correct to speak of a condition or state 

 which cannot be rendered evident to the senses, as a phe- 

 nomenon ? A certain change common to every kind of 

 living matter occurs just prior to the movement of its parti- 

 cles, which universally distinguishes this from every other 

 known state of matter. As the movement is peculiar, its 

 cause must be peculiar, and it seems more reasonable to 

 attribute this to some peculiar power manifested by living 

 matter only, than to an antecedent phenomenon which is 

 different in its essential nature from every other action or 

 change to which the term phenomenon has been applied. 



In truth, when we enter upon the consideration of the 

 cause of the changes in living matter, we get beyond the 

 limits of observation and experiment. It will of course be 

 said that such discussions are therefore futile and out of the 

 province of science. But if this view be accepted we must 

 cease to enquire into the nature of living things almost as 

 soon as we have commenced to investigate the things. 

 The growth, formation and action of the simplest being, 

 and of every elementary unit entering into the formation of 

 the tissues of every living creature, would in that case be 

 to us as a sealed book. And it would be absurd to attempt 

 to describe the processes of growth, formation and secre- 

 tion, as they occur in living beings. In truth the question 

 not only lies at the very root of physiology, but forces itself 

 upon our consideration at every step. It must, therefore, 

 be discussed, and provisional hypotheses may be advanced 

 if only to mark the paths already traversed in the course of 

 our difficult and never-ending exploration. 



The physical school may try to stop all enquiry at this 



