4 THE NATURE AND ORIGIN OF LIFE 



solid as that of the function alcohol or the standard metre. 

 If, on the contrary, instead of employing this objective 

 | method, we define living bodies a priori as " bodies in which 

 something passes like that which / feel passing in myself," 

 we run up against assertions that are unverifiable and we do 

 not obtain a scientific definition. This is what our ancestors 

 did. Thanks to so defective a method, they were led to 

 establish between living and not-living bodies a line of de- 

 marcation that could not be passed over and to consider 

 life as something beyond the reach of experimental study. 



Their method was bad because they really began, without 

 suspecting it, by defining life from its objective characters ; 

 indeed it is only by objective characters that we can know 

 whether bodies are living or not-living. Forgetting this 

 first definition, which they used without suspecting it, they 

 went on to give a second almost as unconsciously, defining 

 a living body as we have said " a body in which something 

 passes like that which every one feels in himself." Such a 

 definition is open to no further verification ; and there is 

 nothing in particular to show how it can be compared with 

 that first and necessary objective definition if we are to be 

 able to say that a body is living at all. Nevertheless they 

 applied the second definition to bodies already defined by 

 the first. 



This is the origin of the anthropomorphic error, which 

 locates a human mental quality in all bodies considered to 

 be living ; and one of the consequences is the belief that 

 an abyss separates living from not-living bodies. 



Learned men who were anxious to destroy so erroneous 

 an idea tried to bridge over the abyss thus opened by an- 

 thropomorphists between living and not-living bodies ; 

 but they too kept to an a priori definition of life and came 

 to the conclusion that life thus defined is universal some- 



