Il8 THE CONCEPTION OF LIFE 



which is brought forward because it makes the totality of 

 vital phenomena more comprehensible. It would be sup- 

 remely interesting to know and we hope that in the future it 

 will be known what consciousness is. But the first question 

 for the biologist is: Is consciousness a true cause? 



And now for our final conclusion. Life is bound to matter. 

 Vital phenomena are alterations of the living substance which 

 we describe by saying that they are transformations of energy. 

 But there always remains the possibility that consciousness 

 cannot be explained mechanistically, that it is neither a con- 

 dition of protoplasm, nor a special form of energy, but some- 

 thing of its own kind, not comparable with anything else 

 that we know, and that it reveals itself by causing transforma- 

 tions of energy. 



There still remains for me to thank you for the attention 

 with which you have honored me, and for the extreme hospi- 

 tality which I have enjoyed here. May the University of 

 Jena grow and prosper! Of her I shall carry with me to my 

 distant home memories to which I shall always return with 

 joy so long as I live. To her I say farewell, and to you, thanks ! 



