306 OBDER AND SUCCESSION OF LIFE. 



scheme. They perceive that life is governed in its distri- 

 bution and existence by the operating forces of the uni- 

 verse ; they learn from* Geology that it has taken a certain 

 order of ascent in time, from lower to higher forms ; and 

 as students of nature, they endeavour to account for its 

 progression by appealing to the forces by which it is mani- 

 festly affected. Philosophically there is no other course 

 left to them. They must deal with life as they deal with 

 the other phenomena of the universe ; and human reason 

 is never more religiously occupied than when earnestly 

 striving to comprehend and account for the designs and 

 methods of the Creator. If there has been any irreverence 

 in dealing with this problem, that irreverence must rest 

 with those who would circumscribe the range of reason, 

 and seek, by unworthy clamour, to deter the human intel- 

 lect from rising to some conception, however faint, of the 

 laws by which the Creator has chosen to develop the 

 phenomena of His marvellous universe. The authors of 

 these hypotheses may be right, or they may be wrong, in 

 their views ; they may ascribe too much or too little to 

 certain agencies : but so long as they honestly endeavour 

 to arrive at the truth, their opinions ought to be gratefully 

 received and treated with candour. As students of science, 

 they abide by scientific methods ; and unless Life is to be 

 altogether removed from the category of Natural Science, 

 they have no alternative but to treat it in all its bearings 

 its rise, progress, and inter-relations as they would deal 

 with any other problem that comes within the scope of 

 their investigations. Higher than mere material pheno- 

 mena, more subtle in its relations than any physical 

 agency, more marvellous in its growth and reproduction 

 than any other department of nature, its comprehension, no 

 doubt, taxes the severest efforts of the human understand- 

 ing j but still, as portion of the universe, it partakes of all 



