I7& Cells; or y Evolution. 



ble. To be supposed to have taken up what has 

 not had justice done to it, or to have failed in do- 

 ing justice to what was taken up, would alike be 

 out of keeping with the respect due to them, and 

 with the real gravity of the subject. The construct- 

 ive view of Life, or what is the Vital Condition, 

 whether that belongs to biology or to psychology, has 

 not been treated here. Again, the several systems 

 or explanations of Progress or Evolution which are 

 in accord with the facts of science, and are no less 

 in accord with sound sense and logic, belong to a 

 constructive and synthetic essay on the subject; 

 not to this critical analysis of prevalent theories, 

 which has here been broached. The spirit that 

 has animated the criticism might appear somewhat 

 destructive; still I trust it has been one of candor 

 and strict truth. For certainly it is the exigency 

 of the situation, not a predilection for the process, 

 which has engaged us all in this precise phase of 

 philosophical criticism. 



L. D. S. 



PRINTED BY BENZIGER BROTHERS, NEW YORK. 



