BEGINNING OF LIFE. 163 



The verdict, as to the beginning of life, is commonly 

 dependent on the standpoint adopted with respect to 

 the possibility of primordial or spontaneous generation 

 (generatio equivoca). This course is, in our opinion, 

 only half correct. The subtlest experiments on spon- 

 taneous generation, whether from organic matter or 

 from constituents not yet combined into molecules of 

 organic matter, have proved indecisive on both sides. 

 Neither the impossibility nor the possibility can be ex- 

 perimentally demonstrated ; it always remains open to 

 the sceptic to say, if nothing appears, that the failure of 

 spontaneous generation is due to the conditions of the 

 experiment ; or if anything does make its appearance, 

 that, notwithstanding every precaution, germs made 

 their way into the infusion. Opinion as to continued 

 primordial genesis still taking place, is thus a mere 

 emanation of the general theory of nature held by each 

 individual. To any one who holds open the possibility 

 that, even now, animate may be evolved from inanimate 

 existence, without the mediation of progenitors, the first 

 origin of life in this natural method is at once self-evident. 

 But even if the proof were given, which never can be 

 given, that in the present world spontaneous generation 

 does not occur, the inference would be false that it never 

 did occur. When our planet had reached the phase 

 of development in which the temperature of the surface 

 admitted of the formation of water and the existence 

 of albuminous substances, the quantitative and qualita- 

 tive conditions of the atmosphere were different from 

 what they now are. A thousand circumstances now 

 beyond our control, and as to the possible nature of 

 which it is needless to speculate, might lead to the pro 



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