What are Animals and Plants? 379 



bridging over. It is true that certain physicists think 



that though spontaneous generation cannot take place now, 



it must have taken place a long while ago ; but if asked 



why they think this, they have no reply but that they 



. cannot otherwise imagine how living creatures could have 



^■er come to be ! But we have had no experience of 



' creatures ' coming to be.' No wonder, then, if we cannot 



imagine it ; for we can imagine nothing of which we have 



not had sensuous experience. The wisest course, I venture 



to think, is at present to say that physical science affords 



us no ground for affirming anything one way or another 



about the mode in which living things came to be, though 



it affirms the fact that all our experience is against the 



spontaneous origin of living things. 



If this conception, that the essential, intimate nature of 

 living things is something beyond the reach of the senses, 

 commends itself, on reflection, to the reader's reason, he 

 will then see how pregnant with true philosophy, and how 

 essentially sufficient is the popular, common-sense reply to 

 the question, ' What are animals and plants ? ' namely, the 

 answer that ' they are living things^ in so far as it implies 

 that each has its own principle of individuation and of spon- 

 taneous internal activity. 



Apart, however, from the acceptance of this view, we 

 have seen that the totality of animals and plants form 

 together a single immense group of creatures, possessing the 

 ten characteristics which we have hereinbefore briefly 

 enumerated, namely, that they are more or less rounded, 

 aqueous, protoplasmic bodies, of very uniform chemical com- 

 position — breathing, feeding, secreting, and groAving by intus- 

 susception, according to definite laws, reproducing their kind 

 by a series of cyclical changes, and more or less able to form 

 habits through their internal spontaneity. 



Such is our answer to the first question : ' What are 



