THE ORIGIN OB' SPECIES 63 



to one's mind, how did all these different species come into 

 ?ing 1 This may be said to be one of the two root-questions 

 oi" biology; the other is, what is the chemical and physical 

 mature of living substance? 



To the question of the origin of species, Linna3us, who was 

 first to define what was meant by the term, answered : " There 

 are as many species as the Infinite Being in the beginning 

 created." Now this answer is deserving of respect and careful 

 examination. The object of all science is to determine the 

 laws of Nature that is to say, those constant modes cf action 

 which, as far as our experience goes, characterise all natural 

 phenomena. Having determined these laws, it is the further 

 task of science to calculate forward to what will be the cumu- 

 lative result of these laws in the future, and to calculate back 

 as to what has been the condition of affairs in the past. Now, 

 as we have already seen, living things, whether plants or animals, 

 originate only from pre-existing plants or animals, but if we 

 interrogate the astronomer or the geologist as to the condition 

 of the globe on which we live, he will inform us that it is a 

 'ooling body, and that at a certain period in past time it must 

 have been a glowing white-hot body like our present sun. At 

 such a temperature living matter could not have existed, since 

 any living matter exposed to a temperature at all approaching 

 this would be resolved into its ultimate elements. We are 

 therefore led to the conclusion that life had a definite begin- 

 ning on our globe, but as to how that beginning was caused 

 Science cannot in the least help us. No process which we 

 can study now will lead to the formation of living out of life- 

 less matter ; and therefore it comes to much the same thing 

 whether we say that living matter owed its origin to some 

 natural process which does not now occur, and about which we 

 know nothing, or that it owed its origin to supernatural process. 



Now if life originated in some way which we can never 

 know scientifically, there is no a priori reason why all the 

 species of animals with which we are acquainted should not have 

 originated at the same time. The chemist, until very recently 

 at any rate, assumed that the eighty odd elements with which 

 he was acquainted had existed from the beginning of time ; 

 and although he now knows that some of the heavier of these 

 are undergoing a slow secular process of decomposition, which 



