7ii.] ON THE PHYSICAL BASIS OF LIFE. 127 



is commonly understood by materialism, seems to me to place 

 himself on a level with the mathematician, who should mistake 

 the xs and y s with which he works his problems, for real 

 entities and with this further disadvantage, as compared with 

 the mathematician, that the blunders of the latter are of no 

 practical consequence, while the errors of systematic materialism 

 may paralyse the energies and destroy the beauty of a life. 



