THE BEGINNINGS OF LIFE, 309 



the theoretical considerations already mentioned con- 

 cerning the nature of Life, a similar possibility could 

 not easily be granted by many, in reference to the 

 origin of living things. Was it not held that the living 

 thing owed its structure or organization to the active 

 influence of a special and peculiar principle ? This 

 c vital principle ' was neither ordinary matter nor ordinary 

 force, neither was it in any way derivable from either 

 of these ; how then could it be supposed that the coming 

 together of matter of any kind could give rise to a 

 living thing? The aggregate of properties, which we 

 designate by the word c Life/ were not supposed to be 

 dependent upon to be, in fact, properties of the material 

 aggregate which constituted the living thing. Life was 

 presumed to be due to the manifestation of a something 

 altogether peculiar of a c vital principle,' which was 

 inseparable from living matter. Doubts, however, as 

 to the truth of this doctrine have gradually multiplied 

 and increased in strength. New means of observation 

 opened up new questions for solution, and the ever- 

 increasing strides of science have wrought the most 

 fundamental changes in our notions concerning Life. 

 Under the influence of the well-established doctrine 

 concerning Persistence of Force and more especially 

 since the clear recognition of the subordinate doctrine 

 as to the Correlation existing between the Physical and 

 Vital forces physiologists have now begun to recognise, 

 and most 'unhesitatingly to proclaim the opinion, that 

 the phenomena manifested by living things are to be 



