72 Causes and Course of Organic Evolution 



Kerner clearly recognizes this when he expresses himself 

 thus: "In former times a special force was assumed, the force 

 of life. More recently, when many phenomena of plant life 

 had been successfully reduced to simple chemical and mechan- 

 ical processes, this vital force was derided and effaced from 

 the list of natural agencies. But by what name shall we now 

 designate that force in nature which is liable to perish while 

 the protoplasm suffers no physical alteration and in the absence 

 of any extrinsic cause; and which yet, so long as it is not ex- 

 tinct, causes the protoplasm to move, to enclose itself, to 

 assimilate certain kinds of fresh matter coming Tvathin the 

 sphere of its activity and to reject others, and which, when 

 in full action, makes the protoplasm adapt its movements 

 under external stimulation to existing conditions in the manner- 

 which is most expedient .^^ 



"This force in nature is not electricity nor magnetism; it 

 is not identified with any other natural force, for it manifests 

 a series of characteristic effects which differ from those of all 

 other forms of energy. Therefore I do not hesitate to designate 

 again as vital force this natural agency, not to be identified 

 with any other, whose immediate instrument is the protoplasm 

 and whose peculiar effects we call life. The atoms and mole- 

 cules of protoplasm only fulfill the functions which constitute 

 life so long as they are swayed by this vital force. If its do- 

 minion ceases, they yield to the operations of other forces. 

 The recognition of a special natural force of this kind is not 

 inconsistent wdth the fact that living bodies may at the same 

 time be subject to other natural forces. Many phenomena 

 of plant life may, as has been already frequently remarked, be 

 conceived as simple chemical and mechanical processes, without 

 the introduction of a special vital force, but the effects of these 

 other forces are observed in lifeless bodies as well, and indeed 

 act upon them in a precisely similar manner, and this cannot 

 be said of the force of life." 



Reference has already been made to the view that, in the 

 simpler colloid bodies, a double electric charge, each of separate 

 sign to its neighbor, invests the colloid molecule. Such might 

 explain, in part at least, the synthesis of the inorganic colloid 

 bodies. But it leaves untouched the question of the formation 

 of colloid polymeric carbohydrates like starch, not to say of 

 the greatly more complex amides, glucosides, and proteids. 



But we have already suggested that — no matter how we 

 view heat, light, chemical affinity, or electricity, as related 



